ch3 attention and consciousness

8/12/2019 CH3 Attention and Consciousness

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Attention and Consciousness

Chapter 3


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Outline

1. The Nature of Attention andConsciousness

2. Attention

1. Vigilance and Signal Detection2. Search

3. Selective Attention

4. Divided Attention3. Cognitive Neuroscientific Approaches to

Attention


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1.The Nature of Attention and

Consciousness

Attention Is the means by which we actively process a limited

amount of information from the enormous amount ofinformation available through our senses, our storedmemories, and our other cognitive processes

Consciousness

More directly concerned with awarenessit includesboth the feeling of awareness and the content ofawareness, some of which may be under the focus ofattention


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ConsciousnessDifferent conceptions of consciousness:

Biopsychological different levels of arousal (sleep, coma, hyperactivity)

Meta-cognitive Reflection on your own cognitive processes

Being aware of cognitive processes

Psychoanalytic Unconscious informationwe do not have access to

it in normal awakened state Phenomenological

What it is like to have an experience of something

Individual, subjective aspects of experience


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Consciousness

Relationship between attention andconsciousness

Attention + Consciousness

No attention + No Consciousness

Attention + No Consciousness

No attention + Consciousness


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?

Can you provide an example of each of thepossible relationships between attention

and consciousness?


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Consciousness

1. Preconscious Processing

Information that is available for cognitiveprocessing but that currently lies outside

of conscious awareness exists at the

preconscious level of awareness


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Consciousness


Priming

Processing of certain stimuli is facilitated byprior presentation of the same or similar

stimuli

Sometimes we are aware of the prime

sometimes we are not Even when we are not aware of the prime,

the prime will influence the processing of the

target


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Consciousness1. Preconscious Processing

Antony Marcel (1983)

Participants had to classify series of words intovarious categories (e.g. pine-plant)

Primes where words with two meanings suchas palm followed by target word (tree or hand)

Task outline:

Is this a plant?

PrimePALM

Target - TREE


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Consciousness


Antony Marcel (1983) (cont.)

- If the participant was consciously aware ofseeing the word palm, the mental pathway foronly one meaning was activated

- If the word palm was presented so briefly that

the person was unaware of seeing the word,both meanings of the word appeared to beactivated


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Consciousness


Tip-of-the-tongue phenomenon

We try to remember something that is knownto be stored in memory but that cannot quitebe retrieved

People who can not come up with the word,

but who thought they knew it, could identify thefirst letter, indicate the number of syllables, orapproximate the words sounds


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Consciousness

1. Preconscious processing

Blindsight

Lesions in some areas of the visual cortex

Patients claim to be blind

When forced to guess about a stimulus in the

blind region, they correctly guess locationsand orientations of objects at above-chance

levels


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Consciousness

2. Controlled Versus Automatic Processes

Controlled processes

Require intentional effort; full conscious

awareness; consume many attentionalresources; performed serially; relatively slow

Automatic Processes

Little or no intention or effort; occur outside ofconscious awareness; do not require a lot ofattention, performed by parallel processing;fast


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Consciousness

2. Controlled Versus Automatic Processes

Many tasks that start off as controlledprocesses eventually become automaticones

Automatization

The process by which a procedure changesfrom being highly conscious to being relativelyautomatic


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?

Can you provide some examples

of automatic and controlled processes?


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Consciousness

3. Habituation

Habituation We become accustomed to a stimulus, we gradually

notice 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 consciouscontrol; occurs directly in the sense organ, not in thebrain


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2. Attention

1. Vigilance and Signal Detection

We vigilantly try to detect whether we did or didnot sense a signal (a particular target stimulus ofinterest)

Vigilance A persons ability to attend to a field of stimulation

over a prolonged period, during which the personseeks to detect the appearance of a particular targetstimulus

Example(Mackworth, 1948) Participants were watching when a clock hand took a double

step

Substantial deterioration after half an hour of observation

Vigilance can be increased with training


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2. Attention

2. Search

Search

Scan the environment for particular features

Whereas vigilance involves passively waiting for asignal stimulus to appear, search involves actively

seeking out the target

Distracters

Nontarget stimuli that divert our attention away from

the target stimuli

Can cause false alarm


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2. Attention

2. Search

2 kinds of search:

Feature search

When we can look for some distinctivefeatures of a target we simply scan theenvironment for those features (e.g. T vs. O)

Conjunction search We look for a particular combination of

features (e.g. T vs. L, p. 85)


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2. Attention

2. Search

Feature-Integration Theory (Anne Treisman) Each of us has mental map for representing the given

set of features for a particular item (shape, size, colorfeatures)

During feature searches we monitor the relevantfeature map for the presence of any activation in thevisual field

During conjunction searches, we can simply use themap of features, we must conjoin two or morefeatures into an object representation at a particularlocation


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2. Attention

2. Search

Similarity theory (Duncan and Humphreys)

As the similarity between target and distracter

increases, so does the difficulty in detecting

the target stimuli

Factors influencing search

Similarity between the target and the distracters Similarity among distracters (p. 86, 87)


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2. Attention

2. Search Guided search theory (Cave and Wolfe)

All searches involve two consecutive stages

Parallel stagesimultaneous activation of all the potential

targets Serial stagesequential evaluation of each of the activated

elements

Movement-Filter theory (McLeod at al.)

Movement-filtercan direct attention to stimuli with acommon movement characteristics

Movement can both enhance and inhibit visual search


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2. Attention


Stroop effect (Stroop, 1935)

Demonstrates the psychological difficulty in

selectively attending to the color of the ink and tryingto ignore the word that is printed with the ink of that

color

Since reading is an automatic process (not readily

subject to your conscious control) you find it difficultintentionally to refrain from reading and instead to

concentrate on identifying the color of the ink


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2. Attention


The cocktail party problem (Cherry, 1953) The process of tracking one conversation in the face

of the distraction of other conversations

Shadowing Listening to two different messages and repeating

back only one of the messages as soon as possibleafter you hear it

Dichotic presentation Listening to two different messages (presenting a

different message to each ear) and attending to onlyone of them


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2. Attention


Filter and Bottleneck Theories

Broadbents Model

We filter information right after it is registered at thesensory level

Morays Selective Filter Model

The selective filter blocks out most information at the

sensory level, but some highly salient messages are

so powerful that they burst through the filtering

mechanism (e.g. your name)


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2. Attention


Filter an Bottleneck Theories (cont.)

Treismans Attenuation Model

1. We preattentively analyze the physical properties ofa stimulus (stimuli with target properties)

2. We analyze whether a given stimulus has a pattern,

such as speech or music

3. We sequentially evaluate the incoming messages,assigning appropriate meanings to the selected

stimuli messages


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2. Attention

3. Selective AttentionFilter and Bottleneck Theories (cont.)

Deutsch and Deutschs Late Filter Model

Placed the signal-blocking filter later in theprocess, after sensory analysis and also aftersome perceptual and conceptual analysis ofinput had taken place

Neissers Synthesis Two processes governing attention Preattentive processes (rapid, automatic, parallel)

Attentive processes (controlled, occur later, serial)


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2. Attention


Attentional-Resource Theories

We have attentional resources specific toa given modality

Explains why we can study and listen to a

music but not listen to news


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2. Attention

4. Divided Attention

The attentional system must perform two

or more discrete tasks at the same time

much better performance at two or more

automatic tasks (driving a car and speaking)

than controlled tasks (writing and

comprehending read text)


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3. Cognitive Neuroscientific

Approaches to Attention

Hemineglect (Martha Farah)

Patients ignore half of their visual field

Attention deficits have been linked to

lesions in The frontal lobe

The basal ganglia


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Stroop Effect

Read through this list of color names as

quickly as possible. Read from right to left

across each line

Red Yellow Blue Green

Blue Red Green Yellow

Yellow Green Red Blue


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Stroop Effect

Name as quickly as possible the color of ink

in which each word is printed. Name from

left to right across each line.

Red Blue Green Yellow

Yellow Red Blue Green

Blue Yellow Green Red

ch3 attention and consciousness

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