last class hypothetico-deductive reasoning/think like a scientist. –hypothetical solutions; test...

Last Class

• Hypothetico-deductive reasoning/think like a scientist.– Hypothetical solutions; Test them one at a time.– Pendulum Problem.

• Think about thinking and reflective abstraction.• Egocentricity and Personal Fable (playing to an

audience); Invulnerability

• Contributions: Task-based, Role of the child, Equilibration as an explanation, Accurate description

• Criticisms: Underestimated, trained (task specific), overestimated adults (garlic powder)

• Fuzzy Trace Theory: reason by processing inexact memory representations, continuum

• Fuzzy Traces are more easily remembered.• Output Interference: Scheduling Effects and Feedback

Effects• Children are biased towards verbatim memories.• They shift to gist during the school years.

– Brainerd & Gordon (1994)

Last Class

HUMAN DEVELOPMENT 1PSYCHOLOGY 3050:

Executive Function, Strategies, and Problem Solving (Chapter 7)

Dr. Jamie DroverSN-3094, 864-8383

e-mail – [email protected]

Winter Semester, 2015

Assumptions of Information Processing

• Information moves through a system or pathway.• Depicted by flow charts.• Input must go through this system of stores in

serial fashion.• Based on the Atkinson-Shiffrin Model (1968).

The Information Processing System


• We can only deal with a certain amount of info at a time, i.e., we have limited capacity.

• If too many operations are added, it will interfere with the execution of other operations.

• Cognition is domain-general.– They rely on the same pool of mental resources.


• Automatic Processes: require none of the short-term store’s limited capacity.– Occur without intention, don’t interfere with other

processes, don’t improve with practice, not influenced by individual differences in intelligence.

– E.g., Frequency of occurrence judgments.


• Effortful Processes: require the use of mental resources for their successful completion.

• Often referred to as strategies or control processes.– Available to consciousness, interfere with other

processes, improve with practice, influenced by individual differences.

– Using a memory strategy.

The Development of Executive Function

• Executive Functions: the processes involved in planning and monitoring what we attend to and what we do with the input.

• It involves:• Working Memory: How much one can hold in the short-

term store and “think about”• Inhibition and resisting interference.• Selective attention.• Cognitive flexibility.

The Development of Executive Function

• Individual differences on executive function are related to higher level cognitive abilities.– Reading, mathematics, IQ

Speed of Processing

• Young children require more time and use more of their limited capacity to execute cognitive processes.

• The results of these limitations are seen on several memory tasks.

• Constraints on time and resources/capacity translate into poorer performance on WM tasks.

• Kail (1991; 1997)– Showed that general developmental changes

in processing speed are similar across different tasks

– Participants aged 6 to 21 yr– Series of reaction time (RT) tasks:

• RT is the time it takes to make a response• Assumption in controlled conditions is that longer

RT means more thinking• Measure of processing load

Speed of Processing

• Tasks varied in cognitive requirements, difficulty– Mental rotation– Memory search– Name retrieval– Mental addition– Visual search

• Pattern of responses varied across the tasks was the same across age – faster RT – increased speed

Speed of Processing

Kail (1991) – Speed of Processing

Speed of Processing

• Kail believes that maturationally based factors are primarily responsible for the age-related changes in speed of processing.

• Brain maturation (e.g., myelin – neural speed) accounts for this in part.

Memory Span and Working Memory

• Usually assessed with tests of memory span.– Unrelated items that can be recalled in order.

• Digit span improves with age.• Span of apprehension has been tested.

– Number of items that can be kept in mind at any one time.

– Amount of information people can attend to at any one time

Memory Span and Working Memory

• Can be measured while one is playing computer games and hears number presented over headphones.– Told to ignore numbers. Later recall numbers.

• Apprehension span increases with age.• A detailed knowledge base in a particular area

facilitates memory for that information.– Eg. Chess experts.

So organized knowledgefacilitates recall from STM:

Chi (1978) – chess expertsversus novices

Development of Working Memory

• Working Memory: involves storage of memory and the capacity to transform information in the short-term system.

• STM is just storage.

• Information Processing: Process info, goes through stores• Sensory-STM-LTM

– Limited Capacity: Deal with a certain amount of info.– Automatic: without intention, don’t interfere, don’t improve– Effortful: available, interfere, improve

• Speed of Processing: Children slow, perform poorly.• Kail: 6-21 (RT task: mental rotation, memory search, name

retrieval, mental addition, visual search).• Memory Span (words, digits) • Span of Apprehension: what can be kept in mind at any one

time.• Knowledge Base, expertise (Chi, 1978)

Last Class

The Development of Working Memory

• Baddely and Hitch (1974) stated that working memory contained a central executive that stores information.

• Also, two temporary systems.– Articulatory Loop: encodes verbal information.

Verbal information may be rehearsed here.– Visuo-Spatial Sketch Pad: encodes visual

information.

Central Executive Articulatoryloop

Visuo-spatialSketch pad

Rehearsal(subvocalize)

Attentional system:

Directs, coordinates “slave systems”

Stores:Visual info

Stores:Verbal info

• Age differences in verbal memory span are caused by developmental changes in the articulatory loop.

• Verbal or phonological information is stored in the articulatory loop.

• Rehearsal of information takes place here.• As we get older, the rate of rehearsal in the

articulatory loop increases.– We rehearse more information.– We remember more information.


Baddeley’s Model: speech rate and memory span linearly related

High

Low

Mem

ory

Sp

an

Low HighRate of Speech (items/sec)

Causes of Speech ratedifferences

Long words Young kidsSlow talkers

Short wordsOlder kidsFast talkers

• Speed of information processing is important.– Speed of articulation is important.– Familiarity with the information is also critical.

• Speed of processing is important to cognitive development in general.


Attention as Resources

• Attention = Concentration• Attention may consume mental resources.• Age differences in the ability to attend to a task

may lead to differences in the ability to allocate limited mental resources.

• There are individual differences and age differences in the ability to stay on task.

• Attention span increases with age.

Inhibition and Resistance to Interference

• Inhibition: Active suppression process, such as the removal of task-irrelevant information from working memory.

• As children get older, they are better able to inhibit inappropriate responses which permits more efficient execution of other operations.

• Resistance to Interference: avoiding performance decrements under conditions of multiple distracting stimuli.

Inhibition and Resistance to Interference

• Can be assessed using the day/night task.– Very difficult for preschoolers.

• Can also be assessed with the tapping task or Simon says.

• Young children show difficult inhibiting speech (Kipp & Pope, 1997).

Developmental Differences

• As children get older, they are better able to execute inhibitory processes.

• Harnishfeger and Bjorklund (1990; 1994) propose that differences in the ability to keep task-inappropriate information out of working memory influences task performance.– Young children can not ignore task-irrelevant info– Can’t keep task irrelevant thoughts out of WM.– Task-irrelevant info clutters WM reducing functional

memory space.

The Development of Strategies

• Memory strategies:– Goal directed processes that are adopted to enhance

cognitive (e.g., memory) performance• Effortful• Deliberate• Usually conscious or explicit


• Even a 2-year-old will use strategies.• The frequency and effectiveness of strategy use

increases with age.• Younger children can be taught strategies that

they do not use spontaneously, which can improve their performance. – Eg. rehearsal– Production deficiency


• Preschoolers do use strategies, even though they lead to incorrect answers.

• Children as young as 18 months use strategies.


De Loache, Cassidy, & Brown (1985)• 18- 24-mo-olds watch as Big Bird hidden in their home

environment (e.g., under sofa cushion)

• During a distraction (attractive toy), kids interrupted play to comment on Big Bird or the hiding place– Looked at hiding location– “strategic” – i.e., do something to aid recall

Utilization Deficiencies

• There is a phase in which young children use strategies as effectively as older children, but do not benefit.

• Miller et al (1990) found that young preschoolers showed no selective strategy.

cage cage house cage house house

cagecagehousecagehousehouse


• Later, children partially use selective strategies.• Later, they use selective strategies, but they do

not help, i.e., utilization deficiency.• Utilization deficiencies are common.


• These deficiencies may be due to lack of mental resources.– Don’t have enough available resources to retain the

information.

• May be due to poor metacognition.• Utilization deficiencies may be beneficial and

may be short-lived.– Coyle & Bjorklund (1997).– But see Schlagmüller & Schneider (2002).

How Do Strategies Develop?

• Children use a variety of strategies to solve a problem.

• Siegler’s adaptive strategy choice model proposes that in cognitive development, children generate a variety of strategies.

• Those that are effective will remain, those that are less effective will eventually decrease in frequency.


• But development occurs as a series of overlapping waves, not through a series of steps.

• Multiple strategies are available, but those that are used change with age.

Last Class• Working Memory: Central Exec, Visuo-Spatial Sketchpad,

Articulatory Loop• Articulatory Loop develops, rehearse faster, rehearse more,

remember more.• Strategies: Effortful, deliberate, conscious.• Production Deficiency, Not always (DeLoache et al., 1985).• Utilization Deficiency (Miller et al., 1990).

– Coyle & Bjorklund (1997).

– But see Schlagmüller & Schneider (2002).

– Limited capacity, metacognition

• Adaptive Strategy Choice Model: Have a number of strategies available. – Those used most frequently change with age.


• A common example to illustrate strategy development is simple arithmetic.

• There are many available strategies.– Sum strategy, min strategy, fact retrieval,

• Children use a variety of these strategies at any one time.

• The frequency with which they are used varies with age.


• Bjorklund and Rosenblum (2002) looked at strategies used by children when playing Snakes and Ladders and performing academic arithmetic.

• Children rarely relied on one strategy only and distribution varied depending on the context.– The sum strategy was most used in the game context,

but least used in the academic context.

• Strategies also varied with the difficulty of the problem.

The Development of Memory Strategies

• AKA Mnemonics.

Rehearsal• Flavell et al. (1966)

– Grade K, 2, and 5 children were shown pictures they were asked to remember.

– Age-related increases in amount of rehearsal (lip movements), in picture recall task

– 85% of GR 5 vs. 10% of GR K.– Within age – more rehearsal, better recall

• greater frequency


• Ornstein et al. (1975) – not only frequency, but type of rehearsal is important – Used overt rehearsal procedure in grade 3, 6, and 8

children.– All kids instructed to rehearse.– Age difference in style of rehearsal, not in frequency– Young children use passive rehearsal.– Older children use cumulative rehearsal.

• older kids showed better recall than younger

Rehearsal sets

Word presented Eighth grade child Third grade child

1. Yard yard, yard, yard yard, yard, yard, yard, yard

2. Cat cat, yard, cat, yard cat, cat, cat, cat, cat

3. Man man, cat, yard, man, man, man, man, cat, yard, man, man, man

4. Desk desk, man, cat, yard, desk, desk, desk, desk, man, cat, yard desk, desk


Organization• The structure discovered or imposed on a set of

items that is used to guide performance.• Often assessed by clustering.• Adults who show high levels of clustering tend to

recall more.• Recall and clustering increase with age.


• Children can be trained to use clustering.• This often leads to positive results.

– Production Deficiency

• Mental Capacity• Perhaps children do not have enough resources

to execute a strategy and perform other aspects of the task at the same time.

• Bjorklund and Harnishfeger (1987) had grade 3 and 7 children study a list of words using organization.

• At the same time they had to press a space bar as fast as they could.– Tapping rates were compared to those from a

baseline measure.

Factors Influencing Strategy Use and Effectiveness

• The more mental effort required from the strategy use, the slower the tapping rate.

• Both groups used the organization strategy.• Both groups showed decreases in tapping rates.• Only the grade 7 children showed recall

improvement.• Strategies are effortful, particularly in young

children.– They are less likely to benefit from strategy use.



• Knowledge base affects the use of strategies.• Having a detailed or elaborate knowledge base

results in faster processing for domain specific information.

• This results in more efficient processing and greater availability of mental resources.


• There are three ways in which knowledge can affect task performance.

1. Item specific effects• Individual items are more richly represented in

the semantic memories of older children than in younger children.

– Leads to easier retrieval.


• When these lists are balanced in terms of meaningfulness, age effects disappear.

2. Nonstrategic Organization• As we get older, there is an increase in

automatic organization.• When highly associated words are used on a

memory test, both young and old children benefit.


• When nonassociated words are used, young children show poor performance compared to older children.

• Semantic relations between highly associated items occurs with little effort.

• Studies show that age differences in recall are eliminated when children have detailed knowledge about the information.– See page 279 (Bjorklund & Zeman, 1982).


3. Facilitating Strategies• Detailed knowledge allows one to used

strategies more efficiently.• Sometimes we realize that we categorize

information during recall, and then continue to use the strategy for the rest of the task.

• Problem solving routines can become automatic


• Metacognition implies that a person is self-aware of his or her thinking.

• Use and availability of strategies require metacognitive awareness.

• Children vary in terms of the strategies they have available, their effectiveness, when they should be used, and their ability to monitor performance.

• Declarative metacognition: explicit, conscious, and factual knowledge a person has about the characteristics of the task being performed, one’s weak and strong points, and strategies that can be used on the task.

• Procedural metacognition: knowledge of when strategies need to be used, and monitoring one’s performance on a task.


• Metamemory: Our knowledge of our own memory.

• Grade kindergarten and one children show little evidence of metamemory (Kreutzer, 1975).

• Young children are often unaware that strategies can help them solve problems.

• When taught strategies, they are often unaware that they facilitate performance and do not generalize.– See Ringel and Springer (1980) on p. 283.


Problem Solving and Reasoning

Four basic components of problem solving:1. Goal

– desired object, state

2. Obstacles– can’t attain goal -- blocked

3. Strategies for overcoming obstacles– deliberate solutions, plans

4. Evaluation of results– Did the strategy work?– Why or why not?– Reorganize

The Development of Problem Solving

• When does it begin?

• Basic cognitive requirement– some sense of goal-directed behavior

• Need precedes action• Not fortuitous discovery

– Beginning of cause and effect (means-end) understanding

• intentionality: make a response to produce an effect

• “If I remove the cloth, I can get the toy”

• Piaget said: by about 8 months• Beginning of the coordination of secondary

circular reactions – Substage 4 of the sensorimotor period

• Infants use one behavior strategically in the service of another– Remove a cloth to get hidden toy



• Willatts (1990) tested 6-8 month-olds with a means-end problems solving task.– distant toy on cloth out of reach– pull cloth, toy moves within reach, get toy

• All infants pulled cloth– 6 mo: lost interest in toy, play with cloth– 8 mo: ignore cloth, retrieve toy

The Development of Problem-Solving

• Chen et al. (1997) tested infants with a complex Willatts-type task -- retrieve out of reach toy (p. 288)– Barrier between baby and toy– Two strings: one attached to toy, one not – also out of reach –

each string is on a cloth that is within reach– Solution: pull cloth, then pull string attached to toy– parents model if baby can’t do in 100 sec

• Question: can they use solution to retrieve other toys in similar problems?– Task (toy) 1 -- 29% correct; Task 2 -- 43%; Task 3 -- 67%– efficiency (goal-directed vs trial/error) increased across trials

• 12 mo-olds use similarity between tasks to solve analogous problems


• Bullock & Lutkenhaus (1988) -- 15 to 35 mo.– build a house by stacking blocks– copy adult-built model

• Youngest infants: little goal-directed activity– Random “stacking”– No reference to the model

• Older children: goal-directed– Monitored performance, self-correction (85%)– Showed pleasure at outcome (e.g., smiling)


• Knowledge of the problem domain and context factors enhances problem solving

• Ceci (1996)– Defined context as the way in which a problem is

represented in long-term memory• Includes knowledge about the task and reason for

doing it

– 10-yr-olds asked to use a joystick to predict where (on a computer screen) a target would land

– Dull version (shapes, colors)– Fun version – video game (capture prey)– Algorithm to solve problem identical– Poor performance on the dull task, excellent

performance on the game task

Reasoning

• A type of problem-solving that requires making an inference– go beyond information given– consider evidence and arrive at a new solution

• 3 types of reasoning– Analogical: use something you know to figure

something you don’t know– Formal: form of an argument, not its semantic

content is critical – formal logic– Scientific: hypothesis generation and testing

Analogical Reasoning

• Using something you know to figure something you don’t know– involves relational mapping– A:B as C:? ; man is to woman as boy is to ? – Similarity relations

• Large individual differences across lifespan; related to IQ• Piaget: formal operational skill• Others argue for earlier signs in toddlers, preschoolers

– Depends on factors such as task complexity, knowledge, working memory capacity, representation

– More than reasoning per se

Analogical Reasoning in Young Children• Holyoak (1984) -- preschoolers, kindergarten• problem: move gumballs from near bowl to far out-of-

reach bowl– can’t leave chair– props -- paper, scissors, aluminum cane, tape, string

• Before solving: hear story about a different but analogous problem and solution using props.– 50% solve gumball problem, remainder successful

after hint– Success depended on perceptual similarity between

objects in story and their objects

Analogical Reasoning in Young Children

• Goswami (1990): relational similarity harder -- bird : nest as dog :?– Problems must be resolved based on relational

similarity, not perceptual similarity.– 4-, 5-, 9-yrs perform at 59%, 66%, 94% correct,

respectively

Scientific Reasoning

• Formal operational skill• Involves generating hypotheses about how

something works and systematically testing them• Identify factors that affect the phenomenon --

vary one factor at a time -- hold other factors constant– e.g., pendulum problem


• Four variables– Amount of weight of the hanging object– Length of the string– Height from which weight is dropped– Force of the push

• Which variable affects pendulum speed?– (answer: length of the string)

• Can only be ascertained by systematic hypothesis testing experimentation– Hold three variables constant and vary the fourth


• One must consider evidence when reasoning scientifically.

• Adolescents and children often don’t do this (see Kuhn et al., 1988; p 296).

• Can improve with practice and training– See CVS study (Chen & Klahr, 1999; p. 296).– 2nd, 3rd, and 4th graders were trained on how to conduct

experiments.– Involved explicit or implicit instructions.– They transferred these abilities to different tests.

Inhibition and ADHD

• Hyperactivity, impulsiveness, difficulty in sustaining attention– Children and adults– 3 to 7% in USA, more common in boys– One-third of these persist into adulthood

• Children with ADHD more likely to have problems in and outside school– Learning– Antisocial behavior– Peer relationships

Inhibition and ADHD

• Barkley (1997) believes the principal cause of ADHD is deficits in behavioral inhibition.

• BI requires the ability to:– Inhibit a prepotent (dominant) response– Stop an ongoing response– Resist interference

• BI influences: – Working memory– Self-regulation of emotion– Internalization of speech

Inhibition and ADHD

• Children with ADHD (compared to those without) do show deficiencies in these areas:– Do poorly on WM tasks– Less proficient at imitating long sequences of actions– Poor sense of time– Adversely affected by delay– More likely to be irritable, excitable – Less likely to use task appropriate strategies

• BI is likely at least part of the problem of ADHD

Cognitive Flexibility

• The ability to shift between rules or tasks.• Can be assessed using the Dimensional Card Sorting

Task.• 3 year-olds have trouble with switch trials. 4-year-olds

do not.

• This shift may be explained by the cognitive complexity and control theory (Zelazo & Frye, 1997).

• There are age-related changes in the complexity of rule systems that one can represent.

• Differences in reflection lead to increased control over behavior and cognition.



• A recursive process whereby the contents of consciousness become an object of consciousness that can be operated on and modified.

• Children acquire rules early and can follow them sometimes. Coordinating rules requires greater conscious reflection, which develops over the preschool years.

last class hypothetico-deductive reasoning/think like a scientist. –hypothetical solutions; test...

Documents

cognitive processes

control processes

memory tasks

processing speed

cognitive flexibility

cognitive requirements

memory strategy

classhuman development