Attention Flashcards
THE MONKEY BUSINESS ILLUSION
- demonstrates phenomenon aka. inattentional blindness
- highlights worrying reality that we’re far less aware of things happening around us than we think
- demonstrates how powerful selective attention is; enables us to focus on task relevant info while filtering irrelevant info out of awareness
- demonstrates limited attention capacity
DEFINING ATTENTION
PASHLER (1998)
- well-studied psychological process BUT notoriously hard to define
JAMES (1890)
- taking clear/vivid possession of objects/trains of thought by the mind
- focalisation/concentration are of its essence
- implies withdrawal from some things to effectively deal w/others
ATTENTION
- we can select a particular object amongst others & subject it to further processing/act upon it
- selection process = generally what we mean by attention though there are some forms of attention (ie. sustained attention)
- attention is NOT = looking at something (change blindness)
CHANGE BLINDNESS
- demonstrates that we can be looking at something BUT not selectively attending to it
- also demonstrates power of selective attention
SELECTIVE ATTENTION
- multisensory; we can selectively attend to visual/auditory/tactile stimuli & switch attention between senses
- selective attention types include:
OVERT - turning head/eyes to orient towards stimulus
COVERT - paying attention to one thing while appearing to pay attention to another
THE COCKTAIL PARTY EFFECT
- covert attention example
- being in a room w/multiple audible conversations but only being able to focus on the person currently speaking to you
- BUT you can also instantaneously switch attention to a neighbouring conversation while appearing to carry on your current one if you hear something interesting
CHERRY (1953): PROCEDURE
- designed dichotic listening experiment to investigate how attention works in a lab
- particularly interested in finding out how much info we filter out from unattended sensory sources
- pps listened to 2 simultaneous sentences spoken into 2 dif ears; attended to 1 sentence & ignored the other; had to shadow (repeat out loud) attended sentences
CHERRY (1953): RESULTS
- pps couldn’t detect most properties of unattended channel (ie. language used/message meaning/content)
- pps DID notice gender of voice/physical attributes (ie. human VS musical instrument)
- aka. attention filters out most info & operates at early processing stage
EARLY SELECTION
- attention operates at an early stage in the processing stream filtering out irrelevant info
- Cherry (1953) -> early selection attention model; stimuli processed according to physical attributes & then selected by attention before reaching awareness & receiving more elaborate semantic analysis; late selection models suggest all stimuli receive semantic analysis before attentional selection filters what enters awareness
- aka. only simple physical attributes made it through the dichotic listening in Cherry (1953)
POSNER (1980): SPOTLIGHT MODEL OF ATTENTION
- argued that attention operates like a spotlight enhancing sensory processing of objects in spatial location to which it’s directed
- endogenous VS exogenous spatial cueing paradigms
POSNER CUEING EFFECTS: INTERPRETATION
- attention increases efficiency of info processing by influencing sensory/perceptual processing
- hypothesised that beh effects of cues = caused by neuronal enhancement/suppression in early visual cortical areas aka. early selection
- attention enhances processing of objects occurring in particular spatial locations
EARLY SELECTION CHALLENGES: CONTEXT EFFECTS
- subjects oft notice their own name/highly relevant info on unattended channels (ie. cocktail party eg)
- how can they be aware of this if all unattended info is being filtered away?
- effect suggests that more info on unattended channels is actually being processed than suspected
EARLY SELECTION CHALLENGES: CONTEXT EFFECTS (MACKAY (1973))
- ambiguous sentences in dichotic listening task
- ambiguous words on attended channel w/priming (biasing) words on unattended channel
- pps’ interpretation of ambiguous sentence = influenced by meaning of biasing word:
1) “money” = referring financial situation
2) “river” = referring to a river - aka semantic info about unattended channel = processed; incompatible w/early selection theory
EARLY SELECTION CHALLENGES: OBJECT-BASED SELECTION
- even when change happens in front of you, you can miss it (aka. change blindness)
- suggests attention may not operate over regions of space
- objects are typically situated in particular locations so how can we distinguish between spatial VS object attention effects?
EARLY SELECTION CHALLENGES: OBJECT-BASED SELECTION (EGLY ET AL. (1994): PROCEDURE)
- pps saw 2 shapes; cued to location on 1 of them
- target appeared either in:
1) same object/same location
2) same object/dif location
3) dif object/same location - conditions 2/3 = spatial distance between cue/target was same BUT in 1 they both appeared in same target; in the other targets were dif
EARLY SELECTION CHALLENGES: OBJECT-BASED SELECTION (EGLY ET AL. (1994): RESULTS)
- reaction time = faster if cue/target occur in same object even if location = dif
- results demonstrate that attention operates in object-based reference frame
LATE & EARLY SELECTION COMPARED
EARLY
- attentional selection operates on objects NOT locations; suggests attention doesn’t operate like a simple spotlight
LATE
- brain seems to carry out substantial processing of stimuli before attentional selection takes place (ie. info about word meaning/whether features in space combine to form objects/etc.)
THE LOAD THEORY: LAVIE (PROCEDURE)
- resolution to early VS late selection debate
- task = decide whether target in circular array = X OR N while ignoring distractor letter off to the side
- 2 IVs:
1) target/distractor congruency (same/congruent VS dif/incongruent letter)
2) perceptual load (distractor variety sharing features w/target (high load) VS equal distractors sharing NO features (low load)) - hypothesis = perceptual load might influence effect of distractors on visual search performance; in particular that distractors would intrude more under low perceptual load > high
THE LOAD THEORY: LAVIE (RESULTS)
- calculated dif in RT when distractor = incongruent relative to congruent
- aka. when looking for X = 40ms slower > when distractor = N > X
- looked at perceptual load effects; pps were less distracted in high perceptual load condition; dif in RT between incongruent VS congruent conditions = lower (4ms) in high perceptual load > low (40ms)
PERCEPTUAL LOAD EFFECTS EXPAINED: LAVIE
HIGH PERCEPTUAL LOAD
- perceptual capacity used up by task of trying to find target (none left for distractor)
- support for early selection aka. monkey business illusion
LOW PERCEPTUAL LOAD
- main task doesn’t use up all perceptual capacity so some left to process distractors
- support for late selection
PERCEPTUAL LOAD EFFECTS CONCLUSIONS: LAVIE
- attention can operate early/late in processing stream depending on overall perceptual load
- point at which filtering of irrelevant info occurs depends on perceptual load of irrelevant task
SCHWARTZ ET AL. (2005): PROCEDURE
- investigated perceptual load/difficulty effects on neuronal lvls; pps performed 2 conditions:
1) low load (detect any red shape)
2) high load (detect specific conjunctions of shape/colour ie. yellow upright T) - main task was flanked by checkerboard stimuli which produce high activation lvls in visual cortex
SCHWARTZ ET AL. (2005): RESULTS
- visual cortex activation due to checkerboard stimuli = much ^ in low load condition aka. neurophysiological correlate of Lavie’s beh data
- high load = pps are so focused on main task that they filter out irrelevant checkerboard BUT filter doesn’t operate well in low load
- effects strangely observed in earliest visual processing lvl
SUMMARY
- attention acts as filter enhancing task-relevant stimuli processing & suppressing task-irrelevant stimuli processing
- attentional orienting can be overt/covert OR exogenous/endogenous
- attention can operate early/late in processing depending on perceptual demands of task
- evidence for late processing demonstrates substantial processing of unattended (unconsciously perceived) stimuli
