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Attention

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The meaning of attention• Term attention doesn’t mean the same thing to all

people

• We apply the term attention to a huge range of phenomena, from the basic notion of arousal and alertness all the way up to consciousness and awareness.

• Attention: the mental process of concentrating effort on a stimulus or mental event; an activity that occurs within the cognitive system, a process.

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Types of attention

• Input Attention– Alertness or arousal– Orienting reflex or response– Spotlight attention

• Controlled Attention

– Selective attention– Mental resources and conscious processing– Supervisory attentional system

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4 interrelated ideas about attention

» First, we are constantly confronted with much more information than we can pay attention to;

» Second, there are serious limitations in how much we can attend to any at one time;

» Third, we can respond to some information and perform some tasks with little if any attention;

» Fourth, with sufficient practice and knowledge, some tasks become less and less demanding of our attentional processes.

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Basic characteristics of attention

• Attention is a mental process that requires mental resources to direct and focus mental processes

• These mental resources are limited; the more attention one tasks requires the less available for performing others

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Alertness and Arousal• The nervous syytem must be awake, responsive, and

able to interact with the environment

• Input Attention: The basic processes of getting sensory information into the cognitive system.

• Explicit Processing: Involving conscious processing, conscious awareness that a task is being performed, and usually conscious awareness of the outcome of that performance.

• Implicit Processing: Processing in which there is no necessary involvement of conscious awareness.

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Reflexive Attention and the Orienting Response

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Posner’s results

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Reflexive Attention and the Orienting Response (con’t.)Posner’s Spatial cuing task

• Benefit/Facilitation: A faster-than-baseline response resulting from the useful advance information

• Cost: A response slower than baseline because of the misleading cue

• Spotlight attention: The mental attention-focusing mechanisms that prepares you to encode stimulus information.

Posner concluded from this and related experiments that the attentional focus subjects were switching was a thoroughly cognitive phenomenon; it was not tied to eye movements or other overt behavior but to an internal focusing mechanism.

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Treisman’s Visual Search: In this panel, search either for a capital T or a boldfaced

letter. In the following illustrations, search for a boldfaced capital T.

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Treisman’s Visual Search

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Treisman’s Visual Search

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Contrasting Input and Controlled Attention

• Treisman’s two conditions provided clear evidence of both a very quick, automatic attentional process and a much slower, more deliberate attention, the type used for the conjunction search. Input attention is the fast, automatic process of attention and the slower one is controlled attention.

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Contrasting Input and Controlled Attention (con’t.)

• Spotlight attention appears to be rapid, automatic, and perceptual. It is thereby distinguished from the slower, controlled or conscious attention process that matches the more ordinary connotation of the term attention.

• Conscious or controlled attention prepares us to respond in a deliberate way to the environment. It is slower, operates in a more serial fashion, and is especially influenced by conceptually driven processes.

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In conclusion…attention

• Three basic senses of the term attention refer to alertness and arousal, the orienting reflex, and the spotlight of attention. These correspond to input attention, a fast process involved in encoding environmental stimuli into the mental system.

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Controlled, Voluntary Attention

• Controlled Attention: Forms of processing in which there is a deliberate, voluntary allocation of mental effort or concentration.

• Selective Attention: The ability to attend to one source of information while ignoring or excluding ongoing messages around us.

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Selective Attention and the Cocktail Party Effect

• Filtering or selecting: When you try to ignore the many stimuli or events around you so you can focus on just one, the ones you are trying to ignore are distractions that must be eliminated or excluded. The mental process of eliminating those distractions, eliminating unwanted messages, is called filtering or selecting.

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Selective Attention and the Cocktail Party Effect (con’t.)

Shadowing Task A task devised by E. Colin Cherry. In this task, Cherry

recorded spoken messages of different sorts on tape, then played the tape to a subject who was wearing headphones. The subject’s task was to “shadow” or repeat the message to the right ear out loud as soon as it was heard. In most of the experiments, subjects were also told to ignore the other message, the one coming to the left ear.

Conclusions: Subjects could report accurately on a variety of physical characteristics of the unattended (left ear) message, but were unable to notice other things about it.

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Broadbent’s Filter TheoryIn Broadbent’s view, the auditory

mechanism acts as a selective filter; regardless of how many competing channels or messages are coming in, the filter can be tuned, or switched, to any one of the messages, based on characteristics such as loudness or pitch.

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Broadbent’s filter theory of selective attention

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Treisman’s Attenuation Theory

Treisman rejected the ‘early selection’ notion embodied in Broadbent’s theory. Instead, she claimed that all incoming messages receive some amount of low-level analysis, including the analysis of the physical characteristics of the message. When the unattended messages yield no useful or important information, those messages are attenuated; they are weakened in their importance to ongoing processing.

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Norman’s Pertinence Model

Donald Norman proposed a useful modification to the Treisman scheme; his model specifically included a mechanism for top-down processing. The model claims that at any instant in time, attention to some piece of information, some message, is determined by two factors, sensory activation and pertinence.

Pertinence: The momentary importance of information, whether caused by permanent or transitory factors.

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Selection Models

• Two things about selection attention:

• First, selective attention can occur very early in the processing sequence, based on very low-level, physical characteristics, as Broadbent proposed.

• Second, it can be influenced by both permanent and temporary factors. Permanent factors include highly important information such as your name and highly overlearned and personally important factors.

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Automatic and Conscious Processing Theories

• Automaticity: Occurring without conscious awareness or intention and consuming little if any of the available mental resources.

• Two explicit theories of automaticity have been proposed, one by Posner and Snyder, and one by Shiffrin and Schneider. They differ in some of their details but are similar in their overall message.

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Posner and Schneider’s 3 characteristics of an automatic

process– The process occurs without intention, without

a conscious decision;

– The mental process is not open to conscious awareness or introspection;

– The process consumes few if any conscious resources; that is, it consumes little if any conscious attention.

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Conscious Processing– The process occurs only with intention, with a

deliberate decision;

– The process is open to awareness and introspection;

– The process uses conscious resources; that is, it drains the pool of conscious attentional capacity

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Automatic and Conscious Processing

The Role of Practice and Memory

Shiffrin and Schneider’s theory of automatic and conscious processing stresses the role of repetitive practice.

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Attention and Automaticity

• Attention is essentially conscious mental resources; we can devote these attentional resources to only one demanding task at a time or to two less demanding tasks, as long as the two together do not exceed the total capacity available.

• The route to automaticity is practice and memory. With repetition and overlearning comes the ability to perform in an automatic fashion what formerly needed conscious processing.

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Disadvantages of Automaticity

Mental processes become more automatic as a function of practice and overlearning. A disadvantage of automaticity is that it is difficult to reverse the effects of practice in an automated task, and automaticity can lead to errors of inattention.

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A Disorder of Attention: Hemineglect

• Hemineglect: A disruption or decreased ability to look at something in the (often) left field of vision and pay attention to it. Thus, hemineglect is a disorder of attention in which one half of the perceptual world is neglected to some degree and cannot be attended to as completely or accurately as normal.

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Drawings copied by a patient with contralateral neglect

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Hemineglect, in conclusionThis order of attention which shows how the

attentional system can be affected by brain damage, thus informing us about normal attention. In hemineglect, the patient is unable to direct attention voluntarily shift attention to the neglected side of space

The evidence suggests that this arises from an inability to disengage attention from a stimulus on the nonneglected side, hence disrupting the process of shifting attention to the opposite side.