Attention: Early versus late selection, and Load theory Flashcards
Dichotic Listening Results
• Rarely noticed when unattended message was
in foreign language……or reversed speech.
• No content remembered
• …even when the same word was presented 35
times!
• Participants shadowed the attended message easily
• When asked about the unattended message:
– Physical characteristics (e.g., sex of voice, large changes in
pitch) usually reported.
Dichotic Listening Task
- Present different messages to each ear
- Subjects attended one ear and ignored the other
- Repeat attended message out loud - shadowing
Broadbent’s Filter Theory (1958)
• An early-selection model - filtering occurs before
incoming stimuli are analyzed to the semantic level
(e.g. surface features but not meaning analysed)
Parts of the filter model
• Sensory store - Holds incoming information for a short period of
time
• Filter - Analyzes messages based on physical characteristics like
tone of voice, pitch, location of stimulus (which ear)
• Detector - Information is processed to determine meaning
• Short-term memory - Holds information for general processing
Problems with early selection
• Moray (1959) - Subjects heard their name in the unattended stream • Triesman (1960) Bilinguals influenced by unattended stream if it is in second language • Gray & Weddeburn (1960): – Response should have been “Dear 7 Jane” – But subjects said “Dear Aunt Jane”
Triesman’s attenuation model
• Key modification to filter theory:
– Unattended messages attenuated rather than lost
completely
Late Selection Models
• Both attended and ignored inputs processed to stage of
semantic (meaning) analysis
• Selection:
– takes place at higher stage of processing
– based on analysis of which input is most
important/demands a response
Late selection models can explain:
Negative priming: Responses to previously ignored stimuli are slowed. MOUSE • E.g. Tipper & Driver (1988): – Task: Categorise red stimuli, ignore green. – Result: Responses to word slowed when preceded by semantically related IGNORED picture • Suggests ignored stimuli is semantically categorised…and inhibited • Response competition interference (e.g. Eriksen & Eriksen (1974
Lavie’s Load Theory
Both early and late selection are possible
the stage of selection depends on the availability of perceptual capacity
perceptual capacity is limited - we can only take in a certain amount at a time
tasks with high perceptual load exhaust capacity
tasks with low perceptual load leave spare capacity
How does this explain “breakthrough”?
words need to meet a certain threshold of signal strength to be detected
thresholds for certain words lowered e.g. own name or words primed by context
Response competition interference e.g. Eriksen and Eriksen 1974
search line for K or P
ignore letter presented above or below line
responses are slowed down when the letter is incongruent and faster when its congruent
shows that the people are processing the meaning of the letter otherwise you wouldn’t get those results
Tipper and Driver 1988
task - categorise red stimuli, ignore green
result - responses word showed then preceded by semantically related ignored words
