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TESTING THE EFFICACY OF ROBOT-TO-HUMAN GOAL DIRECTED ACTIONS By Alissa Baker-Oglesbee A thesis submitted to the Graduate Faculty of Fayetteville State University, North Carolina In partial fulfillment of the Requirements for the Degree of Master of Arts in Psychology DEPARTMENT OF PSYCHOLOGY Fayetteville, North Carolina July 2011 APPROVED BY: ___________________________________________________________ Dr. Daniel Cordoba-Montoya, Chair of Thesis Advisory Committee __________________________________________ Dr. Matthew Lindberg, Professor of Psychology _________________________________________

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  • TESTING THE EFFICACY OF ROBOT-TO-HUMAN GOAL DIRECTED

    ACTIONS

    By

    Alissa Baker-Oglesbee

    A thesis submitted to the Graduate Faculty of

    Fayetteville State University, North Carolina

    In partial fulfillment of the

    Requirements for the Degree of

    Master of Arts in Psychology

    DEPARTMENT OF PSYCHOLOGY

    Fayetteville, North Carolina

    July 2011

    APPROVED BY:

    ___________________________________________________________

    Dr. Daniel Cordoba-Montoya, Chair of Thesis Advisory Committee

    __________________________________________

    Dr. Matthew Lindberg, Professor of Psychology

    _________________________________________

  • ii

    Dr. Sambit Bhattacharya, Professor of Computer Science

    ABSTRACT

    Baker-Oglesbee, Alissa. Testing the Efficacy of Robot-to-Human Goal Directed

    Actions (Under the direction of Daniel Cordoba-Montoya, PhD). Robotic technology

    is rapidly being integrated into human life. One aspect of robotics is as an educational

    tool to aide humans in learning skills. Prior research on the mirror neuron system has

    posited that humans are able to discern the goal of motor actions enacted by humans even

    when the action flow is incomplete. Theoretically, this effect is only observable when

    humans see other humans perform tasks. If this is true, participants should have a more

    difficult time accurately replicating motor tasks when demonstrated by a robot rather than

    a human. Participants viewed either a human or a robot performing motor tasks. The

    participants then attempted the motor task demonstrated while timed and tracked for

    error. Measurements were analyzed revealing significant differences in error within group

    but not between groups. Implications of research are beneficial in the novel combination

    of the mirror neuron system with embodiment theory and in gauging a robot-human

    interaction through a motor-teaching paradigm.

    Keywords: robotics, mirror neuron system, goal understanding, embodiment

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    ACKNOWLEDGEMENT

    Foremost, I would like to formally thank Nathan Oglesbee, Sean Mobeley, Merei

    Clouden, and Ashley Bofill for their assistance in various elements of my work. I would

    like to express my thanks toward the educators in my life…my parents, grandparents,

    nature, and great teachers. Of these teachers, there are a few that stand out and deserve

    individual acknowledgement: Mr. John Spencer, Dr. Sharon Roberts, and Dr. David Scott.

    Each in their own way exposed me to new ideas and ways of thinking. One cannot be

    more grateful for the opportunity to experience that ultimate freedom of thought.

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    DEDICATION

    This labor, representing an immense amount of personal, professional, and

    emotional growth, can be dedicated to no one but my sister Tara Davis and my husband

    Nathan Oglesbee. You both are pivotal in my life and I am grateful for all your love and

    support.

    TESTING ROBOT ACTIONS

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    TABLE OF CONTENTS

    Page

    List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

    List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii

    Chapter I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

    Chapter II. Review of related literature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

    Robotics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

    Mirror neuron system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

    Embodiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

    The current experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

    Chapter III. Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

    Participants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

    Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

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    Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

    Chapter IV. Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

    Chapter V. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

    Chapter VI. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

    References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

    Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

    Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

    Appendix C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

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    LIST OF TABLES

    Page

    Table 1. Descriptive statistics for robot-viewing group . . . . . . . . . . . . . . . . . . . . . 38

    Table 2. Tests for normality by group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

    Table 3. Mean times and standard deviations for time variable

    between groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

    Table 4. Mean difference in time between second and novel puzzles for

    robot-viewing group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

    Table 5. Mean backtracking error differences between groups . . . . . . . . . . . . . . 45

    Table 6. Mean differences between novel and exposed errors

    between groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

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    LIST OF FIGURES

    Page

    Figure 1. Flow Chart of Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 36

    Figure 2. Bar Graph for Time Variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

    Figure 3. Bar Graph for Error Variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

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    CHAPTER I

    INTRODUCTION

    This could be an overly optimistic opinion, but I believe that it is currently a

    remarkable time to be a scientist. Within the past 50 years, we as a global society have

    been witness to a dizzying amount of technological innovation and sophistication. These

    advancements have allowed new insights and methods for scientific study. While some

    inventions have undoubtedly had a dubious impact (the atomic bomb, for example), the

    general purpose of technology is to provide people an easier and more efficient way of

    life. The many implications of technological application can be convoluted though. It can

    be argued that any technological advancement creates its own set of complications. For

    instance, the instantiation of text messaging into our daily lives can make sending a quick

    communiqué simple, yet the overwhelming usage has been tied to increased vehicular

    accidents (Hosking & Young, 2009).

    Whatever a person’s philosophical stance is on the matter, it is unlikely that the

    expansion of technology is not going to stop anytime soon. Some of the latest

    technological developments have brought humans and machines closer than ever before.

    The development of nanotechnology, for example, makes possible the introduction of

    very small robots into our bodies to perform medical procedures or provide sensory

    enhancement (Roberts, 2011). New areas of social research have developed alongside the

    field of robotics as machines have become increasingly integrated into the human social

    sphere. The increasing social sophistication of robotics is prompting new questions

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    regarding a human’s relation to machines (Morana, Movellan, & Tanaka, 2011). This

    study intends to delve into the area of human and machine interaction. In the face of

    increasing incorporation of robotics into human lives, what are the possibilities of these

    exchanges?

    The goals of this study are to measure the capacity a human has for learning from

    a robot in comparison to learning from another human; specifically whether a human is

    able to ascertain a goal from a series of motor tasks from a robot as clearly as from

    another human. The mirror neuron system has been indicated as the physiological area

    for motor learning and goal understanding (Gallese, 2009), and for this reason will be

    examined through existing literature to question its’ function in response to a robot or

    human stimulus.

    Additionally, the theory of embodiment will be examined as a potential theoretical

    fit for future study of the human mirror neuron system. The mirror neuron system has

    been indicated as the physiological area for motor learning (Gallese, 2009). Although

    this element of the study is not directly tested in the design, it proposes a perspective that

    may render deeper understanding of the function of the mirror neuron system while

    underlining the philosophical problems of human-robotic interaction.

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    CHAPTER II

    REVIEW OF RELATED LITERATURE

    The field of robotics is currently expanding into new applications through

    personal robotics. This application of robotic technology finds uses for robots in more

    intimate settings and is focused on creating a relationship between the human user and

    the robot. These roles vary from small non-humanoid robots that vacuum a room or to

    humanoid robots that can serve a user coffee or even teach a foreign language (Turner,

    2006; “ASIMO”, 2010; Kanda, Hirano, Eaton, & Ishiguro, 2004). This type of personal

    interaction has created a need for research on the ability for humans to relate socially to

    robots. This study will examine the human ability to learn motor skills and derive goal

    intentionality from robotic counterparts. An introduction to personal robotics and some of

    the underlying theoretical assumptions of the cognitive scientists who pioneered the

    development of digital computing will follow.

    Physiologically, a human’s ability to learn motor actions and goals has been tied

    to a particular region of the brain known as the mirror neuron system (MNS) (Rizzolatti

    & Craighero, 2004). A brief overview of the history of study of the MNS and description

    of its basic functions will be discussed, as well as some of the more controversial

    proposed functions. The mirror neurons system’s role in learning motor actions, response

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    to different stimuli (biological and non-biological), developmental changes in response,

    and the ability for goal understanding will be of primary focus.

    Finally, to ground this study in a proper theoretical framework as necessitated by

    the goal understanding function of the MNS, a brief review of embodiment theory will be

    discussed. Evidence of the rehearsal of motor actions in the mirror neuron system

    (Gallese, 2009) will be shown to be better understood theoretically through the framing

    of embodiment theory than the framing of the mirror neuron systems function through the

    computational assumptions of cognitive science (the predominant theoretical approach

    within the field). Examples of brain function and perception will be highlighted to exhibit

    embodiment within a cognitive framework as opposed to the classical philosophical

    construct made popular by Merleau-Ponty and Husserl (Dolezal, 2009).

    Robotics

    By and large, the exploration of robotic technology within the field of psychology

    occurs almost exclusively by researchers in the cognitive science area of study. The

    adoption of the study of robotics and artificial intelligence by cognitive psychologists is

    found in the very early history of the field of cognitive science itself. Originally dubbed

    cybernetics by its founders, two key symposiums in Cambridge and Dartmouth during

    1943 presented the original foundations for theoretical development in cognitive science

    (Varela, Thompson, & Rosch, 1993). The primary concepts that emerged as unique to

    cybernetics were computational theory and symbolic informational-processing.

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    At the time cybernetics was developing, the theoretical framework for psychology

    was largely derived from behaviorism. The behavioralist foundations of objectivity and

    quantifiable methodology produced great strides for the burgeoning field of psychology

    by solidifying it as a natural science based on observable phenomenon as opposed to the

    introspective techniques popular in the early history of American psychology. While

    facilitating positive growth for psychology, the focus on overt behaviors also invariably

    stifled any study that involved the mind or its processes. This lack of exploration of the

    processes that occur between the administration of the stimulus to the organism and the

    organisms’ resulting response is referred to as the “black box” approach (Varela et al.,

    1993). The reason behaviorists chose not to engage in discussion or study of the mind lies

    in their methodological philosophy. Observable behaviors were thought to be of utmost

    importance, primarily because it is only observable behaviors that could be viewed in a

    primarily objective sense and thus allow for more reliable and valid measures. The mind

    and its processes are not observable and thereby not objectively reliable or easily

    measured. The behaviorists did not believe that the mind was nonexistent or that it was

    unimportant to explore, but they recognized that an objective methodology offered no aid

    for such study.

    Cognitive science found its way into field discussion by attempting to peer into

    the “black box.” Cybernetics and later, cognitive psychology, found interest in trying to

    define, measure, and specify the mental processes, or cognition, needed to process

    information from stimulus to response. To approach these issues, a new theoretical

    approach was devised that more allowed for a more effective look into the mind and its

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    processes. Cyberneticists reframed psychological science by attempting to resolve a

    classic philosophical quandary, the ‘mind-body problem’ (Anderson, 2001; Dolezal,

    2009; Varela et al., 1993).

    Most famously discussed by Descartes, but acknowledged even earlier in

    philosophical history, the mind-body problem recognizes the apparent gap between

    thoughts and the body or brain. The root of the problem lies in the observation of

    Newtonian physics which states that only matter can affect matter. Thoughts have no

    physical substance and, as it is generally accepted, one may not use thoughts in a way

    that impacts the physical environment. The question arises, how does thought (which is

    non-matter) cause change and movement in the body (which is matter)? Descartes’

    solution, known as Cartesian dualism, states that the mind and body are two separate

    properties, such as a gas and a solid. Descartes believed that the mind was housed within

    the body and interacted with the body through the pineal gland in the brain. This premise

    of mind and body being separate substances, properties, or sides of a spectrum formed an

    ongoing philosophical perspective collectively termed dualism. Although dualistic

    perspectives pervade both scientific and folk psychology, they have yet to effectively

    solve the mind-body problem. Dualism does not provide an answer regarding how the

    intangible mind can bridge the gap to communicate and guide the body (Anderson, 2001;

    Dolezal, 2009; Papineau & Selina, 2002).

    Cognitive scientists largely subscribe to a diametrically opposing perspective to

    dualism. This perspective, termed monism, can be expressed in very different ways. The

    primary division falls between idealism, which states that the physical world does not

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    exist, and materialism which states that the physical world is all that exists. Cognitive

    scientists are generally material monists. Regarding the mind and brain, the fundamental

    principles of cognitive science presume that the mind and brain are the same property or

    that mind is an emergent property of the brain. Following this assumption the study of the

    brain is ultimately study of the mind (Anderson, 2001).

    Computational theory is a strong example of the implicit presence of the material

    monist philosophy, and also illustrates how philosophy can guide physical research of the

    mind and brain. It is no small coincidence that as cyberneticists were honing in on the

    foundations of cognitive science, computer science was moving leaps and bounds away

    from early versions of adding machines to what is more representative of modern

    computer technology. Analog technology was becoming more refined and many scientists

    of the mind saw computer models as a way to conceptualize brain and mind function

    (Abraham, 2002; Rav, 2002).

    During a symposium in 1948, John von Neumann discussed his conceptual design

    for the analog computer. Briefly, this model outlined the input of data, the manipulation

    of data by the central processing unit or executive control into short term and long-term

    memory, and the resulting output. Immediately following von Neumann’s presentation

    was a discussion led by McCulloch on his publication ‘Why the Mind is in the Head’,

    during which he presented the theory that the brain functions in a manner similar to an

    analog computer. In this analogy, the brain operates as the hardware and mental processes

    operate as symbolic information software. Warren McCulloch is credited for creating the

    foundation of the computational theory of mind, officially uniting computer science with

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    psychology (Rav, 2002; Varela, et al, 1993). Many psychology texts today still include

    Von Neumann’s model for information-processing, which, although was originally

    intended to serve as a model for computers, was usurped by psychologists as a model of

    how the brain itself processes information.

    Computational theory posits that the brain functions in a specific manner, as

    directed by algorithms, and performs as an information processor. Information processing

    constitutes taking information from the environment, transcoding that information

    symbolically in the brain to allow for different cognitive functions to act upon the

    information, and when necessary produce some type of output. This system is regarded a

    cohesive integration of mind, brain, and body according to the material monist

    philosophical foundation. This early interdisciplinary marriage between computer science

    and psychology has made possible the creation of artificial neural networks, artificial

    intelligence, robotics, and telepresence technology; all currently expanding fields of

    research and development in private, federal, and academic sectors (Abraham, 2002).

    Within the past decade, society has watched on as robots have begun to vacuum

    carpets (Turner, 2006) and enable people to interact with others remotely via the robot

    itself (Sofge, 2009). More and more often robotic technology is being integrated into the

    private sector and our personal lives. Personal robots are robots that are designed to assist

    with household and office tasks (Wang, Miller, Fritz, Darrel & Abbeel, 2011). According

    to ABI Research (2010), personal robotics is a growing industry with a projected market

    of $19 billion in 2017. During the six years after the prominent personal robotics

    company iRobot® (the maker of the Roomba®) first released their initial models in

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    2000, 3 million robots were purchased (LaGeese, 2008). The International Federation of

    Robotics states there were 2 million personal robots in use in 2004, with a projected

    increase of 7 million by 2008 as cited by Bill Gates (2007). Willow Garage® is a

    burgeoning personal robotics company that has been making popular news with its

    premier open-source personal robot model, the PR2®. Many of the tasks these personal

    robots are capable of allow some simple tasks to be left to the machine, freeing up the

    owner to pursue other activities (Alsever, 2010). The modern advent of personal robotics

    is akin to the revolution that transformed the 1950’s kitchen, freeing housewives from

    day-to-day drudgery through use of modern electric appliances.

    Japan is a country on the cutting edge in the personal robotics industry. Large

    advancements in the field are proving to be of more use to the Japanese population than

    merely providing careers and lending status to the country as a sophisticated player in the

    robotics field. Japan has been experiencing a negative growth rate that is only increasing

    since 2007 (“CIA World Fact Book”, 2010; Yamaguchi & Shen, 2008). The inverse

    relationship between births and deaths in the country has brought difficulties to the

    business sector and robots have been considered as potential clerical workers in the midst

    of a dwindling population (Yamaguchi & Shen, 2008). These are positions that rely in no

    small way upon rapport, trust, empathy, and other emotional capacities for effective

    service.

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    Perhaps one of the most advanced examples is the Honda Corporation’s ASIMO®

    bipedal humanoid robot. The ASIMO® was designed to operate easily within human

    living and work spaces and to perform services for owners (“ASIMO”, 2010). Another

    example is the Mitsubishi Wakamaru® robot model. Touted as the first domestic robot

    with communication capabilities, the Wakamaru® was created specifically to be a house

    sitter, watch over ailing owners, and perform secretarial duties such as answering the

    phone, taking messages, and reminding the owner of meetings (“Domestic Robot to

    Debut”, 2005).

    A slightly different approach to designing personal robots as office workers is

    taken by The Kokoro Dreams Company®, who focuses on developing android models.

    An android is a specialized type of robot that is designed to look and behave like a human

    (Prucher, 2007). Therefore, the Kokoro® robots look very much like real human beings

    and have had great attention paid toward facial expressions, voice pattern and diction,

    and body language. The Kokoro Company® rents its android models to businesses for

    use in many roles. Potential positions are as a fashion model or hostess, a ‘booth

    bunny’ (a slang term for models who sell products at tradeshows) or as a remote access

    device for an absent employee at a meeting (Kokoro Company Ltd., 2008). Other

    suggestions for use include nurse duties, performing as an ambassador, or acting as a

    cabin attendant in an airplane. Curiously, the company states that the robot even “takes a

    spiritual trip from time to time [on] pilgrimages” (Kokoro Company Ltd., 2008). One can

    only imagine the specifications of religiously symbolic usage, but we can infer the extent

    to which robots could be or are currently accepted in various roles in Japanese society.

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    Robots have also been developed to participate as a player in multiple user

    dungeons or MUDs, a role-playing game that relies on player interaction to advance.

    Players explored a virtual world together with robots and collaborated in developing

    strategies to defeat monsters, find success in the mock economy, and develop traits and

    characteristics of the player’s avatar character. Good performance in these individual

    tasks led to an overall goal of game success (Chung-Hsiang & Chuen-Tsai, 2007).

    The use of robotics is also expanding into classrooms. Robots programmed to act

    as a peer tutor and social partner to aid children in learning English were shown to

    improve children’s English language skills significantly over children who did not

    interact with a tutoring robot. A positive correlation between time spent with a tutor robot

    and improved English language skills emerged (Kanda et al., 2004). Given these

    examples, the potential for uses of robots in educational settings is intriguing. Certainly,

    the above studies show how a robot can provide some elements of educational use to the

    benefit of children and very likely, adults. There seems to be a foundation in which

    humans are able to understand and develop skills in certain tasks gained initially through

    interaction with a robot.

    Language, a shared mode of information exchange, may enable robots to act as

    effective teachers for human beings. The skills that are being developed and goals to be

    attained are expressed through language, either spoken or written, and a large part of the

    rapport is undoubtedly created by use of language as well. Language could perceivably

    close the gap for a human in connecting with a robot that may not appear human-like or

    is otherwise not engaging. Perhaps the ability for a robot to teach lies in its capacity for

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    language; however, is it actually possible for a human to learn skills and understand goals

    from a robot on an even more basic level of observational learning?

    There are some notable problems when considering relying on the creation of

    rapport with a robot on a visual or observational basis. First, a preeminent problem in

    creating a basis for contextual understanding of human communication by robots is their

    incapacity to recognize facial expressions (Nikolaidis & Pitas, 2000). On the other side of

    the conversation, humans have exhibited feelings of apprehensiveness and fear in

    reaction to communicating or even looking at robots who appear too human, a

    phenomenon known as the “Uncanny Valley effect” (Mori, 1970). These are some

    problems that might arise when a robot or android approaches more sophisticated levels

    of social exchange. An aesthetically simpler robot could obviate these issues without

    sacrificing the attempt to test the ability for the robot to teach a human through

    observation.

    To circumvent potential robot-to-human language barriers, an examination of

    learned motor skills might be useful. Motor skills are often learned through observation

    and practice, so a motor task is an appropriate way to find whether a robot can

    successfully engage a human and teach a skill without the use of language. Motor skills

    must expand beyond mere mimicry to establish more sophisticated learning. Mastery of

    motor learning can be exhibited through use of the skills initially learned in one task used

    to complete another task, understanding that the skills may be used to reach a similar goal

    in a different task. The overall goal understanding of motor actions can signal more

    meaningful processing than merely visual attending to stimuli. These processes are

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    largely mediated by the motor cortex. Recently, a study has revealed that a specific area

    of the motor cortex lends itself to processing the intended goals of motor actions. This

    area has become known as the mirror neuron system (MNS) (Umiltà et al. 2008).

    The Mirror Neuron System

    To examine the capacity for a human to learn a motor task and achieve goal

    understanding from a robot model, research on the mirror neuron system provides a

    physiologically sound and theoretically expanding framework to guide hypotheses and

    interpret results. The mirror neuron system is located in the motor cortex and is currently

    being explored as a location for more than the delegation and execution of motor tasks, as

    is the traditional functional view of the motor sensory area. Recent research presents

    evidence that the mirror neuron system may be capable of actual learning and rehearsal of

    motor tasks. Previously, learning and rehearsal tasks were considered too complex to be

    performed in sensory areas. As prescribed by cognitive computational theory, information

    that entered a sensory modality was thought to be transcoded and passed on to other areas

    of the brain more suited for higher-order processing (Gallese, 2009).

    The initial physiological evidence detailing the location and function of the MNS

    was gathered from monkeys. Measurements collected from the mirror neuron system

    demonstrated that the neurons fired at the same rate and time for a monkey observing

    another monkey eat peanuts as if the observant monkeys had eaten peanuts themselves

    (Rizzolatti & Craighero, 2004). While the original ‘discovery’ of the MNS was through

    primate brain research, much of the evidence regarding primate’s MNS has carried over

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    to inform the function and location of the human MNS. The location of the mirror neuron

    system in a monkey’s brain is the F5 area of the premotor cortex (Rizzolatti & Craighero,

    2004). Although the evidence for the MNS in humans is indirect, brain imaging

    techniques such as electroencephalography (EEG), transcranial magnetic stimulation

    (TMS), and functional magnetic resonance imaging (fMRI) as well as neurophysiological

    study have created a strong case for the its presence. Human participants have exhibited

    strong activation of the neurons in the lower part of the precentral gyrus, the posterior of

    the inferior frontal gyrus, and the rostral area of the inferior parietal lobe while

    performing motor actions and also while observing other humans perform motor actions

    (Grezes, Armony, Rowe, & Passingham, 2003; Jokisch, Daum, Suchan, & Troje, 2005;

    Kilner, Paulignan, & Blakemore, 2003). These areas are widely considered to be the

    primary area of the proposed mirror neuron system in humans (Gallese, 2009; Gallese et

    al., 2009; Oberman, McCleery, Ramachandran, & Pineda, 2007).

    Prior to this evidence, learning and deriving goal understanding from actions was

    largely regarded as functions of executive cognitive capacities, and thereby primarily

    mediated by the frontal lobe region of the brain (Barsalou, 2008). The apparent mental

    rehearsal and understanding of goals through motor actions by the MNS opens the door

    to considerations that intentionality in some instances may be derived earlier in

    processing than previously believed. Other evidence gathered from the MNS also shows

    that this system may be responsible for categorizations of perpetrators of action, such as

    whether they are human or not human (Shimada & Hiraki, 2006). This automatic

    recognition of a conspecific (a member of one’s own species) seems to affect the

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    rehearsal of the motor action being observed. In the event a motor action is performed by

    an organism that the observer does not recognize as a conspecific, the MNS may not

    activate (Calvo-Merino, Glaser, Grèzes, Passingham, & Haggard, 2005; Shimada &

    Hiraki, 2006). It would be expected that if the motor action does not activate the MNS to

    allow for automatic rehearsal that the motor action may not be performed as well as if the

    action had been carried out by a conspecific (thereby increasing the probability of MNS

    activation). As a robot would generally not be regarded as a conspecific, the MNS may

    play a role in whether humans are able to fundamentally exchange, recognize, and learn

    information from robots.

    Although many accept the prevailing evidence for the existence of the human

    MNS (Andric & Small, 2010; Engel, Burke, Fiehler, Bien, & Rosler, 2008; Gallese,

    2009; Gallese et al., 2009; Iacoboni, 2009), the exact function of the system in humans

    has created several hypotheses and respective counterarguments. A prime example of

    contentious proposed MNS function (or more accurately, malfunction) is the role it may

    play in the development of autism spectrum disorders (cf. Ferber, 2010; Hamilton et al.,

    2007). Another lively area of debate is that of the phylogenetic development of language

    as a coevolving process with the development of the mirror neuron system (Fisher, 2008;

    Ramachandran & Hubbard, 2006). Regardless of the controversy involved in these areas,

    there is almost ubiquitous agreement from researchers from all sides that the human MNS

    is likely to exist. The present study will focus on the relatively accepted aspects and

    functions of the MNS in the processing of observed motor actions and goal

    understanding.

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    Although it is generally accepted that the MNS functions optimally when

    receiving stimuli from conspecifics, questions have been raised about the type of

    conspecific stimuli the MNS will respond to. Interestingly, it has been shown that the

    human MNS will fire in response to a conspecific performing motor actions that are

    impossible. The human MNS was shown to fire when the participant observed impossible

    movements in an artificial human hand, meaning that the hand performed movements

    that are outside of normal physiology (Costantini, Galati, Ferretti, Caulo, Tartaro,

    Romani, et al., 2005). This shows that the MNS can and will respond to motor actions

    outside a preexisting representational motor repertoire and also outside of movements

    that the participant has or can engage in themselves. Such evidence qualifies the ‘direct-

    matching hypothesis’ that proposes that only movements that are already a part of an

    organisms’ motor repertoire will elicit a response from the MNS (Rizzolatti, Fogassi, &

    Gallese, 2001). Evidence suggests that the MNS may develop to respond more to direct

    matches through natural age development or specialization of expert skills (via long-term

    potentiation).

    The sensitivity of the mirror neuron system to different types of stimuli appears to

    change over the development of an individual from child to adult. In exploring the mirror

    neuron system’s response to mediated realities, differences between adult and child

    mirror neuron systems’ firing were tracked while the participants watched live or

    televised actions. They found that a child’s MNS activated in both the live action and

    televised action conditions while an adult’s MNS activated only in the live condition.

    While the children’s MNS seems to react to both mediated or non-mediated motor

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    stimuli, the adult’s MNS seems to be more parsimonious or specialized (Shimada &

    Hiraki, 2006). Their evidence suggests that the MNS fires in response to different stimuli

    over the developmental span of a human, although it is worthwhile to note that the

    children used in the experiment may have had more exposure to mediated stimuli earlier

    in life than the adult participants did. To highlight the potential of mirror neuron system

    specialization through long-term potentiation processes, a separate study tracked a

    dancer’s MNS response while the participant watched dance movements or capoeira (a

    Brazilian martial art that can appear dance-like) movements and found that the dancer’s

    MNS fired more readily during action observation of specialized action (dance) than

    other action sequences (Calvo-Merino et al., 2005).

    In conjunction with Shimada and Hiraki’s findings, this study suggests that an

    adults’ MNS becomes specialized to activate for certain types of motor actions in certain

    mediums, and fires more readily in a context that the motor system has more experience

    with. This specialization seems to occur through both developmental and experiential

    processes. This would suggest that while infant’s brains may behave like sponges,

    tracking any activity to have the opportunity to learn, adult’s brains (or expert’s brains)

    might be more selective about the stimuli it responds to. This evidence is important when

    considering that much of research that focuses on a robot-to-human educational

    interaction focuses on the use of child participants (Chung-Hsiang & Chuen-Tsai, 2007;

    Kanda, Hirano, Eaton, & Ishiguro, 2004), and that any readiness of a child to learn motor

    actions from a robot must be considered to be perhaps a more responsive example than if

    an adult were the participant.

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    The role of the MNS in deriving the goal of a given sequence of motor actions, or

    deriving motor intentionality, is one of the leading theories of proposed function in the

    MNS. Neuroscientists have hypothesized that this function would assist an individual in

    learning motor processes (Gallese, 2009; Gallese et al., 2009; Pineda, 2008; Oberman et

    al., 2007b). Another popular term for this phenomenon is goal understanding.

    If the MNS were deriving action understanding in response to the observation of

    motor sequences, this would suggest that at least some motor goals could be understood

    through bottom-up processing. This would render the processing of the goals as non-

    symbolic and modal in representation. Non-symbolic modal processing is a jarring shift

    from the traditional computational symbolic models of information-processing that

    created the foundations of cognitive science and still dominate theory today.

    Computationally based information-processing models provided the field of psychology

    the means to conceive of covert cognitive functions (often capitulated by bottom-up

    processing of environmental stimuli) that would activate mental models and

    representations accessible by the conscious mind for general thinking processes. The

    theoretical paradigm of symbolic amodal processing mediated by executive function was

    the assumption of much of the cognitive framework and quickly informed other

    experimental subfields of psychology, including developmental, industrial/organizational,

    and social psychology.

    The ability of the brain to perform what is usually considered higher-order mental

    tasks, such as recognizing intentionality, through a bottom-up approach requires an

    alternate theoretical approach to logical computationalism. One of the currently

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    expanding theoretical approaches that is able to account for such processing are the ideas

    of embodiment or grounded cognition, which will be explored later in this paper.

    Needless to say, it is likely this root issue of bottom-up versus top-down processing of

    tasks that results in so much controversy and fascination concerning the study of the

    MNS and its’ functions.

    Yet, there would be no contest without evidence, and there exists ample evidence

    to support the contention that the MNS derives goal understanding from motor actions. In

    one such study, monkeys who had previously been trained to grasp objects were given

    two different sets of pliers, one that opened with the normal squeezing action and another

    pair that opened in reverse fashion by widening the hand’s spread. Monkeys operated the

    pliers while the MNS was recorded. The different operations needed to open the sets of

    pliers allowed researchers to dissociate the neural motor pattern from the neural goal

    pattern (opening). The researchers found the same neural patterns in both cases of pliers

    use, even though the motor operation of each set of pliers was different. This would

    support a hypothesis that the neurons were firing in response to the goal of opening the

    pliers, which is the same across the conditions, instead of merely firing to support the

    differential movement of the hand in order to open the pliers, which would have resulted

    in different firing patterns across the conditions (Umiltà et al. 2008).

    Neural firing in response to goals has been demonstrated in the mirror neuron

    systems of human participants as well. In one study, participants watched videos that

    displayed a series of finger movements: in one condition the fingers moved toward and

    touched red dots (a goal directed movement) while in the other condition the fingers

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    moved the same way without the presence of the red dots (no-goal condition). Increased

    blood oxygenation was detected via fMRI in the MNS in the goal condition, whereas

    there was no increase in blood oxygenation in the non-goal condition (Koski et al., 2002).

    In another study focused on goal understanding, participants who were familiar, but not

    experts, with basketball watched videos of basketball related actions (dribbling, shooting,

    man-to-man plays), which constituted a goal directed condition. Another video showed

    non-basketball related actions (rolling the ball, carrying to goal, players crossing in front

    of others with no action) to constitute a no-goal condition. fMRI readings showed

    significantly greater activation of the superior temporal sulcus and the inferior parietal

    lobule (part of the MNS) in the goal-directed condition (Takahashi, Shibuya, Kato, Sassa,

    Koeda, Yahata, et al., 2008). While there is evidence that some goal understanding is

    occurring in the MNS, it also seems that the activation to goal conditions occurs early in

    the processing of information and that later in processing the system begins discerning

    whether the observation included a conspecific (Costantini et al., 2005). This would seem

    to indicate that there is room for both top-down and bottom-up processing of goals and

    intentionality.

    Another study compared the relative activation of goal understanding in different

    areas of the brain by having participants view videos that displayed a woman drinking

    coffee. Participants would view either an expected flow of events, extraordinary events

    (woman puts coffee cup to ear instead of bringing to mouth), or extraordinary means

    (woman has a power grip on the dainty cup). During exposure to the video stimuli, the

    MNS and the social cognition areas of the brain traditionally considered responsible for

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    ‘mentalizing’ goals – the posterior cingulate cortex, frontal cortex, and superior temporal

    sulcus, were monitored for activation. When the activation results were compared,

    evidence for a complementary system of goal understanding emerged. Participants would

    show more activation in the MNS area when observing of the extraordinary events

    segment compared to the ordinary actions (ordinary means and events) segment. The

    inferior frontal gyrus in the MNS activated whether participants were asked to focus on

    intention or the manner of action. More activation was shown in social cognition areas

    when participants were asked to selectively attend to the intentionality of the woman’s

    actions (de Lange, Spronk, Willems, Toni, & Bekkering, 2008). This evidence shows that

    the MNS consistently activates whether attention is directed to intention or actions (with

    the enhanced activation to extraordinary events vs. ordinary actions showing selectivity

    for intentions) during observation, but that a person must focus on intentions solely to

    activate the social cognition areas. This suggests that these areas work together in a

    complementary system of bottom-up and top-down processing.

    To assess the role of context in deriving intentionality in the MNS, a study was

    performed using a similar instrumental method as the previously discussed study. One

    scene was created in which various sundries and containers were displayed as if in

    preparation for a meal, all items untouched and organized. A separate scene was created

    in which these objects and food items had been obviously consumed and were ready for

    clean up; containers had been empty, crumbs and leftover food was left where untouched

    food items had been previously, a jar was tipped over, and so on. A control scene was also

    used wherein no object was displayed except for a single coffee mug. The mug was

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    included in every scene and was filmed being grasped in two different ways, either using

    the whole hand to pick the cup up around the lip or using a precision grip using the

    fingers at the handle. The whole hand grasp is more suggestive of picking up the cup for

    something other than drinking, and when used in the scene in which everything is ready

    to be cleaned the grasp fits well contextually. The precision grip is contextually fitting in

    the scene where it appears that a meal is about to be enjoyed, and that the cup is being

    picked up to be drank from. Blood oxygenation level-dependent (BOLD) readings of the

    MNS revealed significantly more firing (by way of heightened blood oxygenation) in the

    contextually congruent grip and scene pairing for the precision grip and drinking context.

    This effect was not present in the whole-hand grasp and cleaning context, which is

    possibly because a whole-hand grasp is not used solely for cleaning and could

    conceivably be used to pick up a cup to drink from (Kaplan & Iacoboni, 2006). These

    studies suggest that goal understanding is occurring in the MNS, at least in part, and is

    likely contextually sensitive.

    As mentioned previously, the MNS has been shown to anticipate the goal of a

    series of motor actions. Much of this research has used biological stimuli to elicit

    activation, primarily in the context of a human confederate performing motor actions

    with objects. There has been some research performed testing the ability of the MNS to

    activate in response to non-biological action, although much of this research focuses on

    the apparent self-locomotion of objects such as toys, balls, or other common household

    items (Engel et al., 2008; Eshuis, Coventry, & Vulehanova, 2009). In the face of

    increasing and more personalized technology (especially in the robotics field) an

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    important question is if the mirror neuron system will derive intentionality from

    observation of a robot as easily as from observation of a human.

    To begin to address this inquiry, it is first important to find if the human mirror

    neuron system will even fire in response to non-human movement. There has been a

    range of experiments performed to see if the mirror neuron system will fire in response to

    general non-biological movement, such as self-locomotion in shapes vs. human hand

    movement. In studies such as this, the mirror neuron system does activate to non-

    biological motion, but not as strongly as it does to conspecific actions. These results have

    been interpreted as a side effect of the human tendency to personify moving objects

    (Heider & Simmel, 1944) and also as a tendency to perceive movement as biological

    simply because that is the type of movement encountered most often (Engel, Burke,

    Fiehler, Bien, & Rosler, 2008).

    The mirror neuron system has been shown to fire in response to robotic agents in

    some cases (Gazzola, Rizzolatti, Wicker, & Keysers, 2007; Oberman et al., 2007a;

    Oberman et al., 2007b), and not in others (Kilner et al., 2003; Tai, Scherfler, Brooks,

    Sawamoto, & Castiello, 2004). Although the literature contains mixed results, it does

    seem that more often than not a robot will activate the human mirror neuron system as

    much as a human agent if the robot agent is more humanoid in appearance and is

    performing an action that is similar to a human-like action, such as picking up a ball,

    walking bipedally, or grasping a martini glass. Results have shown though that if one of

    these actions is shown repeatedly, the mirror neuron system habituates to the action and

    responds less aggressively to the robotic movement as compared to a human movement

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    (Gazzola et al., 2007). These results may tie in with the function of goal understanding. If

    a robot performs a singular action, such as picking up a martini glass, this action matches

    well with the observer’s own motor repertoire and also is matched with the potential goal

    of drinking. Yet if the action is performed repeatedly with no conclusion of the action

    (lifting the glass to a mouth, or throwing a ball after grasping) the goal is never actually

    fulfilled and the action is no longer perceived as a goal oriented action, resulting in

    habituation of the mirror neuron system.

    It can be extrapolated from the literature that it is likely that the human mirror

    neuron system seems to fire in response to any motion (non-biological, biological,

    possible or impossible) initially, but that it fires most readily to motion that infers a goal.

    Research on more complex goal understanding using adult participants has been focused

    on conspecific observation primarily (de Lange et al., 2008; Kaplan & Iacoboni, 2006;

    Koski et al., 2002; Takahashi et al., 2008); while goal conditions involving a robot have

    involved moving blocks from one area to another (Erlhagen, Mukovsky, & Bicho, 2006)

    or picking up a glass (Gazzola et al., 2006). The goal conditions in these studies are far

    more simplistic than the basketball paradigm (Takahashi et al., 2008) or the contextually

    rich cleanup or drinking scenario (de Lange et al., 2008). The current study design

    addresses the need for data concerning the ability for a human to recognize and learn

    complex goal understanding from a robot engaged in a motor task.

    There has been some research performed in which robots would perform more

    complex tasks than moving an object to a new location or pick an object up. In one such

    study, children watched either a human or a robot sort cards according to a specific

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    conditional rule. The children were then asked to sort cards according to a different

    conditional rule. It was found that the children who observed the human sort cards had a

    more difficult time in the task than the children who observed a robot sort cards. The

    results imply that the children’s mirror neuron systems were more engaged in simulating

    the human’s actions than the robots, and that they were less able to move on to a new

    condition because of the impact of the human rehearsal condition (Moriguchi, Kanda,

    Ishiguro, & Itakura, 2010). A separate study showed that children were able to infer the

    intended goal of a robot (‘intending’ to put beads in a cup, but ‘accidentally’ dropping

    beads outside of the cup) better if the humanoid robot made eye contact with the children

    during the task than if the robot made no eye contact (Itakura et al., 2008).

    The increased rate of testing of human discernment of goal understanding in a

    robot’s motor actions using children as compared to adult participants is undoubtedly a

    result of the anticipation of the use of robots in primary education settings. Although

    robots are being used primarily for educational interaction with children at the moment, it

    is safe to assume that the growth of the robotics industry will eventually place robots in

    roles through which adults will interact with robots. Also, considering the evidence that a

    child’s mirror neuron system may react differently to alternatively mediated stimuli and

    non-biological motion than an adult’s (Shimada & Hiraki, 2006), it would be unwise to

    assume the data garnered using child participants would be directly replicated in with

    adult participants. Current research is still unclear concerning evidence that of MNS

    activation by robots in adults and very little complex goal-understanding research has

    been studied using an adult population.

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    Embodiment Theory

    Embodiment theory can be viewed as a new and radical perspective on current

    psychological research, or as a philosophical construct with roots as far back as the

    origins of Eastern spiritual and metaphysical thought (Varela, et al., 1993). Although

    there are several iterations of embodiment, the crux of the philosophy of embodiment

    purports that nothing in this physical world exists as a singular and isolated entity,

    including human beings (Barsalou, 2008; Varela, et al., 1993). To illustrate this idea using

    a popular adage; “No man is an island…” (Donne, 1839). Human beings are not simply

    the bodies we observe in the grocery store or the classroom, nor are they the mind alone.

    In fact, even the union of the body and mind would not be a complete human.

    Embodiment states that we are a continuous union of mind, body, and environment,

    including the social environment (Varela et al., 1993).

    More to the point of interest for this work, one aspect of cognitive embodiment

    theory provides that the mind and brain rehearses some external stimuli in modal

    (sensory) areas, rather than transforming all stimuli into logical abstractions of

    knowledge per the computational approach (Glenberg, 1999). This perspective lends

    itself well to what researchers know about MNS function. The MNS is rehearsing

    observed motor stimuli in the motor area of the brain rather than acting as simply an input

    area (Gallese, 2009). I am proposing that the MNS be considered a hard example of

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    embodiment processing in humans. This proposal, to my knowledge, is novel in the field

    of psychology. Rather than asking if the human MNS can learn motor actions from a

    robot as well as a human, I feel it is more correct to ask whether the human MNS can

    embody motor actions from a robot as well as a human.

    The MNS is not the only example of modal processing in the brain. There have

    been other modal processing areas and phenomena that highlight how embodiment can be

    an attractive theoretical approach for further research and exploration. It has become

    clear that the symbolic computational approach does not adequately describe or explain

    information-processing in all instances.

    Perhaps the most famous example of a cognitive process best understood through

    embodiment theory is that of color vision. It has been understood for some time at this

    point in the sciences that color does not exist in the natural world as we perceive it, but it

    also does not reside solely within our brains. Color is actually a phenomenon, an

    interaction between the environment and our visual perceptual faculties (Varela et al.

    1993). This relationship highlights the dynamic exchange between the brain and the

    environment, a contrast to the one-sided linear process operating within a static

    environment as in symbolic processing theories.

    Another example of a well-known psychological phenomenon that melds well

    with embodiment theory is phi phenomenon, or apparent motion, as described by Gestalt

    theorist Max Wertheimer in 1912. Phi phenomenon is the subjective perception that two

    alternately flashing lights that are horizontally arranged in the field of vision appear to be

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    one light moving back and forth. Wertheimer successfully rejected other explanations of

    the phenomenon by illustrating that the perception was a product of the stimuli

    movement (environment) and our perceptual system (mind and body) (Ammons &

    Weitz, 1951). Arguably, many of the observations made by the Gestalt psychologists

    are intrinsically descriptions of embodied phenomena.

    A more modern example of embodied processing is Shepard and Metzler’s visual

    representation experiments in the 1970’s. Participants were presented with sets of two

    three-dimensional figures and asked to determine whether the set contained the same or

    different figures. The sets that contained the same figure would present that figure at

    different degrees of rotation. The researchers found a direct linear relationship between

    the time it took to determine whether the figure was indeed a rotated version of the

    primary stimuli and the degree of rotation of the figure (Shepard & Metzler, 1988).

    Similar findings were produced in a separate experiment (Kosslyn, 1973) in

    which a participant viewed a picture of an object (ex: an airplane) and was then asked to

    focus on one particular element of the object (a propeller). After viewing the object for a

    set amount of time the picture would be removed from view and the participant would be

    asked to recall if the object had an element that would have been out of the area of

    directed focus for the participant (vertical or horizontal fins on the tail). Results showed

    that the length of time it took for participants to answer was relative to the distance of the

    parts of directed focus and parts questioned about but not focused on.

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    These experiments strongly suggest that the visual information available to

    conscious processing was not represented in a symbolic manner as prescribed by

    computational theorists, but were represented visually in their mind by actually

    ‘picturing’ the stimuli. These are strong examples of modal representation of information

    and thereby embodied cognition. This evidence parallels the rehearsal process of the

    MNS (Gallese, 2009).

    Although the proposal for the MNS to be considered a structure that operates at

    least partially in an embodied manner is novel, the potential for human embodiment of

    robotic actions without consideration of the MNS has been studied at least once. In this

    singular study, children played a drumming game with a humanoid robot. Both the child

    and the robot had their own drums, and the game involved the children and robot taking

    turns playing their respective drums. The children were asked to mimic the beats that the

    robot would play. The first condition of the experiment would have the robot and child in

    a room together (‘face-to-face’). The second condition was mediated, the children

    watched a live video feed of the robot. In the final condition the children would play in

    the same room as the robot, but the robot was behind a partition so they would not see the

    robot but could hear the drumming. Children reported more enjoyment playing the game,

    played longer, and made significantly fewer errors in the live condition than in either the

    mediated or listening condition. It would appear that children embodied the live robot’s

    actions better than the other conditions (Kose-Bagci, Ferrari, Dautenhahn, Syrdal, &

    Nehaniv, 2009).

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    There are two important differences to be considered when comparing this study

    design with the current design: first, this experiment used an extremely human-like robot

    (the robot looked very much like a child) and one would expect a greater degree of

    embodiment from what could essentially be considered a conspecific visually and by

    motor movement. Secondly, the research as outlined previously in the robotics section of

    this work has shown that children’s mirror neuron systems are more predisposed to react

    to robotic or mediated agents easier than an adult’s MNS (Shimada & Hiraki, 2006). This

    does not negate the importance of the studies findings, merely suggests that there is a

    need for varied inquiry.

    These differences highlight that the current study’s use of adult participants and a

    non-humanoid robot addresses a neglected area of study in the embodiment literature.

    The suggestion that the MNS functions in a manner that supports the growing literature

    on embodied cognition is a novel proposition. There is no proposal from the embodiment

    literature concerning goal understanding, or whether embodiment of a robot will or will

    not enable goal understanding to occur more easily. My hopes are that this experiment

    can lend itself to further experimental study and consideration of embodiment theory in

    robotics and psychology.

    The Current Experiment

    The current study is focused on assessing the potential for human motor learning

    from a robotic teacher. Human-robot interactions are becoming an important aspect of

    human life, and the personal robotics area is rapidly growing due to consumer demand.

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    Personal robotics will play an increasing role in home service, and the use of robotics in

    education is beginning to be explored. Motor learning and goal understanding will be an

    important factor in building better interactions between humans and robots.

    The capability for a human to learn motor actions and understand goals or

    intentionality from a robotic counterpart is currently best assessed through findings on the

    human mirror neuron system. Evidence has been gathered that shows that the human

    mirror neuron system will fire most readily to conspecific movement, but will also fire in

    response to non-biological motion such as a robotic arm movement. The mirror neuron

    system will fire most readily to familiar movements, but will also fire in response to

    impossible movements. The mirror neuron system also fires in response to goal related

    sequences of movement more significantly than randomized series of movements. Some

    study has been performed to assess the readiness of the human mirror neuron system to

    fire in response to robotic movement, but no work has been done to assess the ability for

    humans to perceive goal intentionality from a robot’s sequence of motor actions.

    Determining whether humans are able to derive intentionality from a robot’s motor

    sequences is the main point of question in this study. If humans are better able to

    understand motor goals from conspecifics, the group that watches a robot perform motor

    tasks should perform worse than the group who watches a human perform motor tasks.

    Embodiment theory allows the current study to be viewed in a larger theoretical

    perspective. The human mirror neuron system operates through automatic rehearsal of

    motor actions when performed by a conspecific. This rehearsal is processed in the human

    mirror neuron system as if the observer had performed the action his or her self. The

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    simulation process is performed modally in the motor system and does not require

    transmission of the information to other cognitive areas for learning (Gallese, 2009). Goal

    understanding of motor actions has also been proposed as a modal function of the mirror

    neuron system (Umiltà et al. 2008). Both functions, but especially the goal understanding

    function (Hans, Henk & Ruud, 2012), had been previously determined to be solely top-

    down symbolic processes while the modal areas served as sensory inputs (Palmer, 1999).

    Embodiment theory proposes that at least some forms of cognition are represented and

    interpreted modally, making the proposed functions of the mirror neuron system a good

    example of embodied cognition. Current embodiment literature has very little study on

    whether a human can embody information originating from a robot, and no work on

    whether goal understanding or intentionality can be embodied. These missing points in

    the literature are the secondary focus of this study. If the mirror neuron system is able to

    embody the motor actions and intentionality of the robots, there should be little difference

    in the times between groups on tasks and the groups should show similar execution of the

    tasks in terms of repetition of observed movements. This study questions whether a

    human can embody robotic motor actions and goal understanding as competently as

    human motor actions. I hypothesize that a human will not embody a robot’s motor actions

    as effectively as they would embody a conspecific’s motor actions. I also hypothesize that

    a human will have less overall goal understanding of a robot’s motor actions than a

    human’s motor actions.

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    CHAPTER III

    METHOD

    The present experiment utilized a between-groups design (human-viewing x

    robot-viewing), the first group was exposed to a human video stimulus and the second

    group was exposed to a robot video stimulus. In the robot-viewing condition the

    participant viewed two videos of a robot solving two different tangram puzzles. Tangram

    puzzles consist of different geometric plastic shapes (ranging in size from 1 inch to 3

    inches in area) that may be arranged to create large shape and figure silhouettes. In the

    human-viewing condition the participant viewed two videos of a human solving the same

    two tangram puzzles. After viewing each video, the participant was asked to solve the

    puzzle they had just observed being solved and then solve a final novel tangram puzzle

    they had not seen solved. The dependent variables are the amount of time it takes to

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    complete the puzzles (a measure for each of the three trials) and how many times tangram

    pieces are removed from the puzzle form while the participant is solving. The removal of

    tangram pieces from the puzzle form during a randomized selection of solving time

    served as a count for error.

    Participants

    Forty-one students from Fayetteville State University were tested in total, with 22

    participants in the human condition and 19 participants in the robot condition. Six

    participants were excluded from data analysis; 1 participant because of researcher error in

    administration of the experiment tasks, and the other 5 for failing to complete two of the

    three puzzles within the time limit of 15 minutes. Group counts after exclusions were 16

    participants in the human group and 15 participants in the robot group. Twenty-six

    participants were female and 5 were male. No significant differences were found on any

    performance measure between males and females. No other demographic data was

    collected on the participants. Nearly all participants volunteered for participation through

    the university Participant Pool website. Four participants volunteered for participation

    with the researcher directly. Undergraduate students received grade points for

    participation in the research.

    Instruments

    The original experimental design was to use a Hanoi Tower puzzle as one of the

    tasks, but was later cut due to the inability of the robot or the grabber arm to complete the

    task. This task could allow for time measurement, a move count, and an error count as it

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    requires the user to follow a specific pattern to correctly solve. Sets of tangram pieces

    were chosen as an alternate puzzle to the Hanoi Tower puzzle, and puzzle forms were

    drawn and laminated. For the human video, a female volunteer was filmed solving 5

    different tangram puzzles. The camera aperture was focused on only her hands, the

    tangram pieces and the puzzle form. Two of the puzzles with the shortest solution time

    were chosen to serve as the human group instruments. After selecting the videos, they

    were coded movement-by-movement and timed. To film the robot video stimulus, a long

    arm grabber was purchased to simulate a robotic arm. The grabber arm was 30 inches

    long with a gripping set of two arms with suction cups at the end which can be closed by

    the pull of a trigger at the opposite end of the mechanism. Using the arm, the two puzzles

    selected in the human condition were replicated for the robot video stimulus. The puzzles

    were solved in an almost exact method to the human condition, although some elements

    were unable to be replicated; such as picking up certain pieces and manipulating them in

    the hand, or moving more than one piece simultaneously on the board. The stimulus films

    were edited and copied to a DVD using iMovie™ and Microsoft Movie Maker™. The

    puzzle solving was not edited aside from a frame rate manipulation and the insertion of a

    blue screen at the movies’ starting and ending points.

    As using the grabber arm slowed down the overall time to solve the puzzles in

    comparison with the human condition films, the robot films had the frame rate increased

    by 125%. This manipulation permitted the alignment of the different film conditions. It

    was not readily apparent that any manipulation had been performed on the films. No

    participant inquired or remarked about the speed of the robot condition.

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    Participants watched the video stimuli on a 27-inch television that played the

    DVD through a Zenith® DVD player. Participants viewed the films from a chair and

    table centered in front of the television from a distance of 5 feet. Participants were filmed

    solving the puzzles with a Kodak® EasyShare® digital camera and timed with a

    stopwatch application on a Samsung® cellular telephone. The camera aperture was

    focused on only their hands, the tangram pieces and the puzzle form. Data analysis was

    performed using SPSS® v. 19 and G*Power™ v. 3. Any and all data collected from

    participants were secured in a room only accessible by the researcher and Fayetteville

    State University psychology faculty.

    Procedure

    Experimentation was performed on an individual basis. The experiment was

    approved by the Internal Revue Board of Fayetteville State University (Appendix C).

    After signing the consent forms (Appendix B) the participants were read the oral script

    (Appendix A) by the researcher describing what they would be doing, which contained

    information as to whether they would be watching a human or a robot solving puzzles.

    The robot-viewing participants were read an additional statement to prime expectations

    for viewing a robot: “The arm you will see is being manipulated by a robotic software

    program.”

    The script also informed participants that they had 15 minutes to solve each

    puzzle and that they could quit at any time. To try and ensure the participants were fully

    paying attention to the movies, they were asked to count the number of moves used to

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  • 37

    solve the puzzle, operationalized as how many times the tangram pieces were moved into

    the black area of the puzzle. After the script was read participants had a chance to ask

    questions and then participants watched the first film. Once the film had reached the blue

    screen in between the first and second puzzles, the researcher paused the film and asked

    the participant how many moves they had counted while watching the video. After

    receiving an answer the researcher brought the participant the puzzle they had just

    observed being solved from an adjoining room where the puzzles were kept out of sight

    of the participant. The researcher filmed the participant working on the puzzle until it was

    solved or the allotted time of 15 minutes had passed. The participant’s time was tracked

    along with the filming.

    After the first puzzle trial had been completed or timed out, the researcher cleared

    the puzzle from the table and removed the puzzle to the adjoining room. The researcher

    reminded the participant that they were to count the moves used to solve the puzzle and

    started the film again, which played through the blue screen and the second puzzle. After

    the film ended, the researcher asked the participant for the moves they had counted and

    then retrieved the puzzle they had just observed being solved from the adjacent room.

    Participants worked on the second puzzle trial while being filmed until the puzzle was

    either complete or they ran past the allotted time of 15 minutes. The puzzle was then

    cleared from the work area and the researcher brought out the final puzzle, which was

    novel to the participants in that they had not seen the puzzle solved on a video or seen the

    puzzle form before. Participants solved the novel puzzle under the same conditions as the

    first two puzzle trials. After either solving or failing to solve within time, the researcher

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    indicated to the participant that they had completed the experiment and thanked them for

    their participation. At that point the participant was offered a copy of the experiment’s

    consent form for their own records. A visual representation of the procedure of the

    experiment follows in Figure 1.

    Watch first film

    Solve first puzzle

    Watch second

    Solve second

    Solve novel

    Figure 1

    CHAPTER IV

    RESULTS

    Time and error served as the dependent measures to constitute an overall measure

    of learning. Time of completion was the elapsed time of the participant’s engagement

    with the puzzle. Time was measured until the participant would lay their hands on the

    table along the sides of the puzzle form indicating completion as directed, or until the

    participant requested to end the puzzle trial before completion. Error was operationalized

    as the number of times a participant would remove pieces from the puzzle form in a

    randomized 1-minute video sample from each puzzle trial. The error variable is called

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    ‘backtracking’, a term created by the author for this study. It should be noted that there

    was one participant who did not backtrack during any puzzle trial (making them an

    outlier on this variable), and another participant was missing a backtracking measure in

    one of their three trials due to video failure during experimentation. These two

    participants had group means placed into their missing values as an alternative to deletion

    from the small sample size.

    When assessing normality of the data the time measures were found to be

    positively skewed. A log transformation was applied to the time measure, which

    completely normalized the human-viewing group’s distribution, and nearly all of the

    robot-viewing group’s distribution. After transformation, the robot-viewing group still

    exhibited slight skewness in the first puzzle trial data as shown in Table 1. This

    abnormality in the robot-viewing group’s first puzzle trial distribution is due to the high

    number of participants that were unable to solve the puzzle before the 15-minute limit. As

    the main considerations in analysis pertain to the second and third (novel) puzzle trials

    there should not be grievous errors due to the first puzzle trial’s slightly skewed

    distribution. The error variable satisfied assumptions of normality.

    Table 1

    Descriptive statistics for robot-viewing group

    Table 1

    Descriptive statistics for robot-viewing group

    Table 1

    Descriptive statistics for robot-viewing group

    Table 1

    Descriptive statistics for robot-viewing groupMeasures First Second Novel

    Skewness 1.262 .352 -.469Std. Error of Skewness .550 .550 .550Kurtosis 1.829 -1.182 -.288Std. Error of Kurtosis 1.063 1.063 1.063

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    Table 1 Descriptive TableTable 1 Descriptive TableTable 1 Descriptive TableTable 1 Descriptive Table

    To assess the significance of the violation of normality, a Shapiro-Wilk test was

    performed on each group distribution. In the human-viewing group the time variable for

    the first puzzle trial, W(16) = .82, p < .05, and the backtracking variable for the first

    puzzle trial, W(16) = .88, p < .05 were both significantly non-normal. In the robot-

    viewing group the time variable for the first puzzle trial W(16) = .87, p < .05, and the

    backtracking variable for the second puzzle trial W(15) = .87, p < .05 were both

    significantly non-normal. Full results of the Shapiro-Wilk and the Kolmogorov-Smirnov

    may be found in Table 2. Due to the near equal sample size in the groups and the

    independent t-test’s robustness to non-normality, statistical analysis of the data is

    considered appropriate. Assumptions for homogeneity of variance were met

    satisfactorily.

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by group

    Table 2

    Tests for normality by groupTime and Error

    Measurements, by group

    Time and Error

    Measurements, by group

    Kolmogorov-SmirnovKolmogorov-SmirnovKolmogorov-Smirnov Shapiro-WilkShapiro-WilkShapiro-WilkTime and Error

    Measurements, by group

    Time and Error

    Measurements, by groupD df p W df p

    First puzzle time Human-

    viewing

    .231 16 .022* .829 16 .007*First puzzle time

    Robot-

    viewing

    .200 15 .109 .877 15 .043*

    First puzzle errorHuman-

    viewing

    .230 16 .023* .883 16 .044*

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    First puzzle error

    Robot-

    viewing

    .209 15 .076 .908 15 .127

    Second puzzle

    time

    Human-

    viewing

    .164 16 .200 .972 16 .874Second puzzle

    timeRobot-

    viewing

    .163 15 .200 .934 15 .310

    Second puzzle

    error

    Human-

    viewing

    .246 16 .010* .893 16 .062Second puzzle

    errorRobot-

    viewing

    .200 15 .110 .876 15 .041*

    Novel puzzle

    time

    Human-

    viewing

    .134 16 .200 .916 16 .148Novel puzzle

    timeRobot-

    viewing

    .158 15 .200 .951 15 .536

    Novel puzzle

    error

    Human-

    viewing

    .150 16 .200 .957 16 .607Novel puzzle

    errorRobot-

    viewing

    .227 15 .036* .889 15 .065

    Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Table 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives TableTable 2 Descriptives Table

    An independent t-test on the time variable between groups showed no significant

    differences. Table 3 and Figure 2 depict the mean log transformed times for the human-

    viewing (n = 16) and robot-viewing (n = 15) groups across puzzle trials. Although not

    significant, the second puzzle trial times are approaching significance, t (29) = 1.72, p < .

    05, with the human-viewing group (M = 2.10, SD = .415) completing the puzzle faster

    than the robot-viewing group (M = 1.87, SD = .309).

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    Table 3

    Mean times and standard deviations for time variable between groups

    Table 3

    Mean times and standard deviations for time variable between groups

    Table 3

    Mean times and standard deviations for time variable between groups

    Table 3

    Mean times and standard deviations for time variable between groups

    Table 3

    Mean times and standard deviations for time variable between groups

    Puzzles and groups M SDFirst Puzzle Human-viewingHuman-viewing 2.49 .483

    Robot-viewingRobot-viewing 2.30 .464Second Puzzle Human-viewingHuman-viewing 2.10* .415

    Robot-viewingRobot-viewing 1.87* .309Novel Puzzle Human-viewingHuman-viewing 2.22 .281

    Robot-viewingRobot-viewing 2.37 .357Note: *Mean values approaching significance at p < .05Note: *Mean values approaching significance at p < .05Note: *Mean values approaching significance at p < .05Note: *Mean values approaching significance at p < .05Note: *Mean values approaching significance at p < .05Table 3 Means and Standard Deviations TableTable 3 Means and Standard Deviations TableTable 3 Means and Standard Deviations TableTable 3 Means and Standard Deviations TableTable 3 Means and Standard Deviations Table

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    To further explore the difference between the groups on the second puzzle trial, a

    within-subjects paired samples t-test was performed. The paired samples t-test failed to

    reveal a significant difference, t (15) = -1.12, ns, between the mean time on the second

    and novel puzzle trials for the human-viewing group (n = 16), (M = -.121, SD - .432), as

    expected by the results shown in Table 3. The results for the robot-viewing group (n = 15)

    were highly significant, t (14) = -4.72, p < .05, in the time difference between the second

    and novel puzzle trials as seen in Table 4. A visual representation of this data may be seen

    in Figure 2.

    Table 4

    Mean difference in time between second and novel puzzles for robot-viewing group

    Table 4

    Mean difference in time between second and novel puzzles for robot-viewing group

    Table 4

    Mean difference in time between second and novel puzzles for robot-viewing groupPaired Puzzles M SD

    Second puzzle time – Novel puzzle time

    -.497* .408

    Note: *Significant at p = .05, 2-tailedNote: *Significant at p = .05, 2-tailedNote: *Significant at p = .05, 2-tailedTable 4 Within-Group Paired t-Test Table 4 Within-Group Paired t-Test Table 4 Within-Group Paired t-Test

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    Figure 2

    Results of an independent t-test examining puzzle backtracking error between the

    human-viewing group (n=16) and the robot-viewing group (n=15) found a significant

    difference between groups in the novel puzzle trial, t (29) = 2.49, p < .05. The human-

    viewing group (M = 4.31, SD = 1.778) committed significantly more errors than the

    robot-viewing group (M = 2.73, SD = 1.751). This data is shown in Table 5 and

    represented visually in Figure 3.

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    Table 5

    Mean backtracking error differences between groups

    Table 5

    Mean backtracking error differences between groups

    Table 5

    Mean backtracking error differences between groups

    Table 5

    Mean backtracking error differences between groupsPuzzles and groupsPuzzles and groups M SDFirst Puzzle Error Human-viewing 2.81 1.759First Puzzle Error

    Robot-viewing 2.53 1.922Second Puzzle Error Human-viewing 2.25 1.693Second Puzzle Error

    Robot-viewing 1.80 1.859Novel Puzzle Error Human-viewing 4.31* 1.778Novel Puzzle Error

    Robot-viewing 2.73* 1.751

    Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Note: *Significant at p < .05Table 5 Means and Standard DeviationsTable 5 Means and Standard DeviationsTable 5 Means and Standard DeviationsTable 5 Means and Standard Deviations

    Figure 3

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    Exploratory variables

    As the design of this study focused on measuring a behavior that is unable to be

    directly measured (learning), several different methods were used in an attempt to

    appropriately measure the implied behavior. While not all of the methods provided

    significant results, consideration of the methods and their results are still descriptive of

    learning processes in their own right. These results may be used to develop future

    research as a means of narrowing the scope of measurement.

    The initial working definition of error as a variable was the number of ‘board

    clears’ a participant would make throughout the course of solving in each puzzle trial. A

    board clear was operationalized as each time a participant would clear the puzzle form