Attention (4b) Flashcards
(13 cards)
Outline the idea that sensory of attention of like a bottleneck
It would be too overwhelming to manage every sensory input that we have
–> attention is like a GATEWAY
–> the information we actually attend to is the bottleneck result
How is attention defined?
How we are able to select a particular object amongst others and subject it to further processing or to act upon it
–> attention however is VERY HARD TO DEFINE
Example research (unnamed?) - where presentation is Parafoval v Foval - what % of participants miss the critical stimulus
25% of people miss critical stimuli when they are presented PARAFOVEALLY
65% of people miss critical stimuli when they are presented FOVEALLY (centre of vision!!)
What is attention NOT?
NOT the same as looking at something
CHANGE BLINDNESS? INATTENTIONAL BLINDNESS studies demonstrate that we can be looking at something but not selectively attending to it, and therefore not aware of it
Outline selective attention (including its subtypes)
Selective attention is the cognitive process of focusing on a particular object, task, or stimulus in the environment while simultaneously ignoring other irrelevant or distracting information.
OVERT: turning head or eyes to orientate
COVERT: appearing to pay attention to something else
What is the cocktail party effect
The idea that we can focus on a conversation in a loud environment, by blocking out other stimuli and loud noises
- assessed by Cherry (1953) during his dichotic listening task
–> subjects could not detect most properties of the unattended channel
COULDN’T DETECT:
–> language used
–> meaning of the message
–> content
COULD DETECT:
–> gender
–> physical attributes (eg. human v musical instrument)
attention filters out most info - suggests it operates at an early stage in processing
What is early selection
Attention operates at an early stage in the processing stream:
–> after physical analysis but before awareness and response
semantic analysis (extracting meaning) happens later
What are the problems with early selection theories of attention
The fact that we can process “higher level” information about unattended stimuli
Context Effects: often subjects notice their own name, or other highly relevant information, on the unattended channel
somehow the brain knows what’s been said
–> BIASING WORDS: tested by MacKay (1973) - biasing words can have a clear effect on how we interpret conversation
What is the spotlight model of attention (Posner 1980)
Posner argues that attention operates like a spotlight, enhancing sensory processing of objects in the spatial location to which it is directed
–> it is possible to be aware of things happen to around a fixed focus
PROCEDURE/MATERIALS:
- Showing that people respond faster to a target stimulus when their attention is directed to the target’s location beforehand.
A cue appears indicating where a target might show up. If the target appears where the cue pointed (a valid cue), reaction times are faster. If the target appears elsewhere (invalid cue), reaction times are slower.
Endogenous cueing - voluntary (requires control)
Exogenous cueing - automatically directed by peripheral cue
Interpretation of Effects:
o Attention increases efficiency of information processing
–> Posner hypothesised that this was caused by neuronal enhancement in early visual cortical areas (early selection)
o Attention enhances processing of objects occuring in particular spatial locations
What is selected - objects or location? (Egly et al. 1994)
Challenge: differentiating between the effects of spatial attention and the effects of object-attention
Egly et al. (1994) used a cueing paradigm to direct the attention of participants to different objects and locations
- spatial separation between cues was the same
FOUND:
- attentional selection operates on OBJECTS, not locations
- again demonstrates a reasonable amount of preattentive process
EVIDENCE FOR LATE SELECTION: because the visual scene must be subject to a reasonable amount of visual processing before attention operates to determine what is selected
*demonstrates substantial processing of unattended - therefore not consciously perceived stimuli
Compare early selection with the idea of late selection
Early Selection:
- after physical analysis
- before awareness and response, and semantic analysis
Late Selection:
- after physical and semantic analysis
- before awareness and response
Resolution to early v late: Nillie Lavie: Load Theory
Attention can operate early or late in the processing stream depending on overall perceptual load
–> The point at which filtering of irrelevant information occurs depends on the perceptual load of the relevant task
Lavie’s Task
–> Task is to decide whether the target letter is an X or an N, while ignoring distractor letters
–> IVs are target/distractor congruency, and perceptual load
Explain perceptual load effects (high v low)
High Perceptual Load (eg. having lots of letters)
- perceptual capacity is used up by the task of trying to find the target
- so none left for distractor
- support for EARLY SELECTION
- think back to monkey business illusion
Low Perceptual Load
- the main task does not use up all your perceptual capacity so there is some left to process the distractors
- support for late selection
