Attention 1

Question 1

Why is attention necessary?

Answer 1

Attention is necessary for consious perception

Question 2

Define: Attention

Answer 2

The process by which the mind chooses from among the various stimuli that strike the senses at any given moment.

Question 3

The Cocktail Party Effect Cherry (1953)

Answer 3

In a noisy environment people are able to focus their attention on a single conversation and also to covertly shift their attention to listen to a more interesting conversation than the one they pretend to be engaged in.

Question 4

Early sensory areas

Answer 4

Located in the top and back areas of the brain - visual area, primary auditory area, somatosensory areas

Early-selection mechanisms would influence the processing of sensory inputs before the completion of perceptual analysis.

Question 5

Late sensory areas

Answer 5

High-level areas - parietal cortex, anterior temporal lobe, dorsal area

Late-selection mechanisms would act only after complete perceptual processing of the sensory inputs, at stages where the information had been recorded as a semantic or categorical representation (e.g. chair)

Question 6

Evidence for Early Selection

Cat Study

Answer 6

What: Placed an electrode into the cochlear nucleus (very early in processing) and recorded the activity when the cat was resting and a tone was played, when the cat was “excited” as it was next to a mouse in a jar and a tone was played, finally resting again once the mouse had been taken away.

Found: Reaction to the sound was less when attention was on the mouse - evidence for early selection?

Limitations: Not very well controlled as cat could move around so intensity of the tone could differ between conditions.

Question 7

Evidence for Early Selection

Dichotic Listening

Answer 7

Different auditory information is presented to each ear of a participant. The participant is asked to “shadow” (immediately repeat) the auditory stimuli from one ear.

Question 8

Evidence for Early Selection

What effect did we find from the dichotic listening task?

Answer 8

Measuring the ERP in a dichotic listening task showed that attention can effect the strength of early sensory processing as when participants were tested for the left ear and attended to the left ear they had a bigger response than to when they attended to the right ear.

Question 9

Exogenous attention

Answer 9

Reacting to unexpected, salient, and automatic external stimuli; bottom-up processing

Question 10

Endogenous attention

Answer 10

Sustained, top-down attention that helps focus on specific information for longer periods