attention- lecture 6 Flashcards
3 features of attention
- selectivity- lets us process specific info while ignoring (inhibiting) the rest
- limited capacity- can only process s much info at once (divided attention)
- sustainability- dificult to attend to the same thing over extended periods of time (sustained attention). vigilance, alertness, mind-wandering
basic categories of attention
bottom-up attention
top-down attention
bottom-up attention
when attention is directed based on properties of sensory input (e.g. shiny objects, loud noises)
top-down attention
when attention is directed based on internal states (e.g. habits, knowledge, goals)
voluntary vs involuntary attention
voluntary- related to current goals, manipulated with instructions, incentives
involuntary attention- unrelated to current goals, distraction, capture of attention, manipulated with stimuli
not always opposite in practice- only distraction when contrary to goals
exogenous attention
- controlled by external events (e.g. sudden changes in brightness or sound)
- rapid but brief attention
endogenous attention
- controlled by internal states (knowledge, goals)
- slower acting but long lasting attention
selective attention
- cherry 1953- cocktail party effect-how does 1 follow convo at cocktail party when its noisy
- attention needs to select 1 message for processing and inhibit the rest
- often dont hear unattended messages
- shadowing task- over repitition of info presented in 1 message- content of unattended= unnoticed, change in language= unnoticed
cocktail party effect
cherry 1953
early selection theory
- broadbent 1958
- parallel inputs are filtered before accessing 1- prevents overloading of limited capacity mechanism, based on early sensory properties (e.g. location)
- cocktail party effect- we are unaware of unattended info because it undergoes sensory but not semantic processing before being filtered
broadbent 1958
early selection theory
challenges to early selection
- some info from unattended is noticed during dichotic listening
- so some processing of unattended message must occur
- cannot be completely filtered out
treisman 1960
attenuation theory
attenuation theory
- unattended info not fully inhibit but attenuated after initial sensory processing
- unattended info doesnt usually reach semantic processing threshold but some types may leading to occassional breakthroughs
late selection theory
- deutsch & deutsch 1963
- tried to explain why semantic info is somtimes processed
- proposed- all channels semantically analysed following sensory processing, filtering happens later in STM after semantic processing based on importance of inputs, only most important inputs acted on and remembered
deutsh & deutsch
late selection theory
visual attention
covert and overt
covert vs overt attention
- in vision, attention is linked to where someone is looking- recall fovea has more detailed vision
- overt- gaze shift accompanies shift ofattention
- covert- attentional shifts occur in absence of eye movements
is attention needed for vision
studied using search tasks
- parallel processing- when what youre looking for pops out from a crowd of irrelevant objects, some visual features are processed simultaneously
- serial processing- when u need effortfully scan to find somthing, especially when what makes targets different from distractors depends on conjunctions of features, no single visual feature that isolates target
- not just 1 or the other- search efficiency varies on spectrum
- as target differ more from distractors, search gets easier
attention awareness
- we are aware of suprisingly little info
- change blindness- dificulty noticing changes when dynamic signals are missing
- inattentional blindness- failure to notice events that arent attended
posners attention neworks
- alerting network- mainaining vigilance over period of time, right frontal and parietal areas, norepinepherine
- orienting network- directing attention, 3 operations- disengage, move, engage, frontal parietal and subcortical areas, acetylcholine
- executive network- target detection and sleective responding, midline frontal areas and lateral frontal cortex, dopamine
unilateral neglect
- deficiency in attending to 1 half of the visual field
- typically damage in right inferior parietal lobe with neglect of left visual hemifield
- patients dont notice stimuli in left hemifield if theres somthing else to attend to in right hemifield
- deficit in attention not vision
biased competition theory
- proposed to explain how attention affects response of individual neurons
- if 2 stimuli appear in neurons receptive field, neurons response is in between a strong and a weak response- competing for neurons response
- but if 1 stim is attended, neurons response is more like the response to that stim- strong when attending to preferred, weaker when attending non preferred
- imputs compete foe neural responses, attention can bias that competition towards relevant stim
