Cognitive Psychology: Selective Attention
early filter looks right
-Goldstein waffles on this -in studies where people seem to get semantic information—looks likely that they are actually rapidly switching attention to the ear they're supposed to be ignoring -attention is biased not to stay in one place bc many things are either threatening or meaningful to someone which causes them to switch focus
Triesman's Experiment
-Participant hears a statement in attended ear and at a random time hears another statement in the unattended ear -Results: mix the two statements when the participant speaks — BUT people don't realize they're doing this
late filter evidence
-Triesman's experiment — mixture of 2 messages -Corteen & Wood — GSR Response
early filter
-attention filters out on the basis of physical features -everything, including the unattended ear, is processed for physical characteristics -only attended stuff is processed for semantics (meaning) -screen out unattended perceptual information early on; separated based on broad physical features; only on stimuli selected for further processing
selective attention
-attention must be selected exactly because it is limited -the focus of attention on one particular stimulus or task at the exclusion of other stimuli.
why early filter is suspicious
-attention will shift -cocktail party phenomenon
dichotic listening experiment
-method to study early vs. late filter -task in which people wearing headphones hear different messages presented to each ear -person is told to only listen to left ear (attended ear) and not right ear (unattended ear)
Top Down Selection: Overt
-moving your eyes -also called visual search unlike bottom up bc 1) you have a specific thing in mind that you want to attend to 2) searching by color is relatively easy 3) searching by meaning = very hard and slow
Top Down Selection: Covert
-no eye movements (ie, seeing out of the corners of your eyes) -Posner's beam metaphor
results from dichotic listening experiment
-people don't remember words from unattended ear -people don't notice if speech is played backwards or if language changes in unattended ear -people DO notice if a pure tone (gender of speaker) is played or if there is a gap conclude: early filter — everything, including physical aspects are heard but don't know the meaning unless attention is focused on it
consequence of selectivity
-sometimes you're attending to the wrong thing -an animal only focused on one thing leads to problems later in the future -early filter vs. late filter
visual neglect
-spatially-based neglect of attention -typically a consequence to a stroke in the right parietal hemisphere of the brain -give evidence that attention and spatial phenomenons are really selected by attention rather than objects selected by attention
cocktail party phenomenon
-talking with a friend and you hear your name from across the room, your attention moves to wherever you heard your name involuntarily -selective attention: in a crowded noisy room we are aware of other conversations around us if they are about us; we hear our name over other conversations -early filter does NOT present this phenomenon
bar experiment
Results: different parts of the parietal lobe are maximally active during between-object shifts and within object shifts — it is possible that both mechanisms are present --example of diversity where there could be unity
strategies to avoid distraction
Strategy 1: avoid distracting stimuli Strategy 2: Habituate
late filter
attention filters only after meaning is analyzed filtering input after the brain processes the meaning
Posner's beam metaphor
attention is like a "spotlight" that enhances perceptual processing/speeds up processing where it is directed
Corteen & Wood: GSR Response
form of classical conditioning -Phase 1: Shock associated with 3 city names — train until GSR response (sweating of the hands which indicates anxiety/nerves) -Phase 2: they shadow an irrelevant message from attended ear and the unattended ear gets words, plus occasional city names — GSR response shown when city name is played which indicates the unattended material is evaluated for meaning
disengage
if damaged — posterior parietal cortex is damaged
move
if damaged — superior colliculus
engage
if damaged — thalamus
Broadbent: early selection model (AKA "bottleneck" model)
incoming auditory info restricted early on in a filtering process: 1.) sounds enter sensory memory 2.) filter identifies message you're supposed to attend to based on physical characteristics of the sound; lets only this stimulus through 3.) detector uses higher-level processing to get at semantics of the stimulus 4.) message enters short-term memory (ie, you become aware of it) Called a bottleneck because the filter stage restricts information flow
later filter theories
led some researchers to proposed that all stimuli are evaluated for their semantic content as well as their physical properties
Neural Basis of the Beam Model
neural evidence shows damage to different parts of the brain supports 3 separate processes—"disengage," "move," then "engage" attention brain damage impairs one of these processes depending on its location; has an effect on reaction times in precueing task
looking for a red car in a parking lot
overt— easy to pick out a red car since the color stands out
4 problems with Posner's beam metaphor
predictions that don't work: -moving attention further doesn't take any longer -moving attention isn't slowed down by intervening stuff/stimuli -stuff outside the beam is actively inhibited -implies attention only selects space/location
Bottom up selection
sometimes things attract attention such as specific color, movement and meaning physically salient and meaningful = bottom up attention effects
looking for Waldo
very hard because it is a configuration of visual cues
Strategy 1: avoid distracting stimuli
when someone asks a question, people often look off into the distance because they're avoiding distracting stimuli faces are socially important and it is hard not to attend to them --example: people putting phone away when studying (changing environment)
special selection
when you selectively attend to just one word, based on color, even though another word overlaps it in space implication: when you switch, you are switching not to a location in space but to another object or object part
Strategy 2: Habituate
with continued exposure, distracting stimuli no longer demand attention greater effect if stimuli doesn't change much — harder to habituate to music than a refrigerator hum & harder to habituate to things that MOVE --example: if a detailed painting was behind someone you were having a conversation with—you would habituate bc it is static