Attention 1

8/2/2019 Attention 1

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General Psychology

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Attention, Sensation and

Perception Sensation: incoming of sensory messages

Attention: focus on stimulus

Perception: meaningful sensation

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The meaning of AttentionAttention

Is the means by which we actively process a

limited amount of information from theenormous amount of information availablethrough our senses, our stored memories, andour other cognitive processes

Sternberg (1999): Attention acts as a means offocusing limited mental resources on theinformation and cognitive processes that aremost salient at a given moment

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Consciousness: More directly concerned withawareness it includes both the feeling ofawareness and the content of awareness, some ofwhich may be under the focus of attention

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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 canattend to any at one time;

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

Fourth, with sufficient practice and knowledge, some tasksbecome less and less demanding of our attentionalprocesses.

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Controlled Versus Automatic Processes of Attention

Controlled processesRequire intentional effort; full conscious

awareness; consume many attentionalresources; performed serially; relativelyslow

Automatic Processes

Little or no intention or effort; occuroutside of conscious awareness; do notrequire a lot of attention, performed byparallel processing; fast

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Controlled Versus Automatic Processes Many tasks that start off as controlled processes

eventually become automatic ones due to repetitivepractice

Automatization The process by which a procedure changes from being

highly conscious to being relatively automatic

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Theories of automaticity Two main theories have been proposed, one by Posner

and Snyder, and one byShiffrin and Schneider. Theydiffer in some of their details but are similar in theiroverall message.

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Posner and Schneiders 3 characteristics of an

automatic process The process occurs without intention,without a conscious decision;

The mental process is not open to consciousawareness or introspection;

The process consumes few if any consciousresources; that is, it consumes little if anyconscious attention.

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Controlled processing The process occurs only with intention, with a deliberate

decision

The process is open to awareness and introspection

The process uses conscious resources

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Habituation Habituation

We become accustomed to a stimulus, we graduallynotice it less and less (e.g. music and studying)

Dishabituation A change in a familiar stimulus prompts us to start

noticing the stimulus again

Sensory adaptation Physiological phenomenon; not subject to conscious

control; occurs directly in the sense organ, not in thebrain

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Types of attention1. Selective Attention

2. Vigilance and Signal Detection Theory

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1. Selective AttentionThe 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 onjust one, the ones you are trying to ignore aredistractions that must be eliminated or excluded. Themental process of eliminating those distractions,eliminating unwanted messages, is calledfiltering orselecting.

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Selective Attention

Shadowing Task/ Dichotic listening task

Different messages are presented to each of aparticipants ears

S/he is asked to shadow or repeat one of themessages on-line

Questions about the message in the unattended ear

Only the physical characteristics of unattendedmessage could be reported e.g. gender of voice(Cherry, 1953)

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Broadbents Filter Theory-

Selective Attention

In Broadbents view, the auditory mechanism

acts as a selective filter; regardless of howmany competing channels or messages arecoming in, the filter can be tuned, or

switched, to any one of the messages, basedon characteristics such as loudness or pitch.

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bottleneck


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Broadbents filter theory of selective

attention

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Broadbent Model But counter evidence suggests that the meaning of

the unattended message, not just its physical

characteristics, were being processed e.g. Moray (1959)you always detect your name in the

excluded message

e.g. Treisman (1964a)bilingual participants able to

recognise the identity of two messages in differentlanguages

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Treismans Attenuation TheoryTreisman rejected the early selection notion

embodied in Broadbents theory. Instead, she

claimed that all incoming messages receive someamount oflow-level analysis, including theanalysis of the physical characteristics of themessage. When the unattended messages yield no

useful or important information, those messagesare attenuated; they are weakened in theirimportance to ongoing processing.

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Normans Pertinence ModelDonald Norman proposed a useful modification tothe Treisman scheme; his model specificallyincluded a mechanism for top-down processing.

The model claims that at any instant in time,attention to some piece of information, somemessage, is determined by two factors, sensoryactivation and pertinence.

Pertinence: The momentary importance ofinformation, whether caused by permanent ortransitory factors.

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Response selection model Deutsch & Deutsch (1963)

Allmessages processed perceptually and for meaning.No filtering, no attenuation

Bottleneck comes at the response stage, when only oneof the messages can be responded to

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Selection Models- conclusion Two things about selective attention:

First, selective attention can occur very early in theprocessing sequence, based on very low-level, physical

characteristics, as Broadbent proposed.

Second, it can be influenced by both permanent andtemporary factors. Permanent factors include highly

important information such as your name and highlyoverlearned and personally important factors.

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Sustained attention/ vigilance Persons ability to attend to a field of

stimulation over a prolonged period of timeperson seeks to detect the appearance of aparticular target (Sternberg, 1999)

A vigilance task usually involves waiting forsomething unpredictable to happen

e.g. radar operator

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Signal detection theory

A theory which says that there is no absolutethreshold for sensation. The detectiondepends on their physical energy and oninternal factors such as relative costs and

benefits related to the detection of stimuli. Perceptual sensitivity to stimulisensitivity of

perceiver to detect the stimuli

Decision criterionperceiver adopt an internal

criterion of overall sensory activity in deciding

whether a signal is present or not.

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Response bias:when signal is weak then it dependson observers detection ability. It includes observersattention to stimulus, motivation and expectancy and

other non sensory factors.

Noise: there are several kind of distractions while wetry to detect a specific stimulus like lack of attention,motivation, fatigue

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Task: warn of incomingaircraft

Are the blobs enemy aircraft?Or just noise (e.g. clouds)?

Decision depends onsubjective criterion: how big

must the blobs be to beaircraft

Decision has consequences: If you miss an aircraft, people

might get killed

If you mistake noise for aircraft,fuel, manpower & resources arewasted

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Decision outcomes & consequences

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Hit Falsealarm

Miss Correctreject

yes

yes

no

no

DECISION:should you alert the air

force?

SIGNAL: are the blobs real enemy aircraft?


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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 andpay attention to it. Thus, hemineglect is a disorder of

attention in which one half of the perceptual world isneglected to some degree and cannot be attended to ascompletely or accurately as normal.

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Drawings copied by a patient with

contralateral neglect

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Attention 1

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