selective attention- hearing and vision Flashcards
What did Colin et al study about speech messages in hearing?
focused attention to one of two simultaneous speech messages- shadowing, i.e. repeating aloud one of the messages, is successful if the messages differ in physical properties (location, voice, amplitude). Not successful if the messages differ only in semantic content e.g. novel.
Ppts cannot recognise when it goes from meaningful to meaningless. People can only recognise physical rather than semantic changes.
What is the cocktail party effect?
The ability to selectively attend to either speaker by focusing on mouths, also called shadowing/dichotic listening
What is the bottleneck effect?
The stage at which it becomes hard to filter out one thing and not the other
What did Broadbent measure in his dichotic split span experiment?
So though aware of unattended speech as sounds with pitch, loudness and phonetic characteristics we do not seem to process their meaning. If required to extract identity or meaning from two sources, ppt has to switch attention filter between them- slow and effortful process.
Describe Broadbent’s filter model
Inputs are attended message and unattended message
Sensory store -> selective filter -> higher level processing -> working memory
Based on physical properties e.g. pitch and loudness
What features are stored in sensory (echoic memory)?
Features of all speech sources that are processed in parallel
Is filter all or none?
No- there have been examples of partial breakthroughs of meaning of unattended speech in shadowing experiments. There seems to be more semantic processing going on in unattended messages
What does information that passes through the selective filter achieve?
Recognition of words/objects/faces, activation of meaning, representation in memory, control of voluntary action, access to conscious awareness.
Why are late selection theories limited?
They do not explain why selection on the basis of sensory attributes is so much more efficient than selection on the basis of meaning
What did evidence (that words could activate their meanings) inspire?
Late selection theories- theory that both attended and unattended words processed up to and including identification and meaning activation; relevant meanings then picked out on the basis of permanent salience or current relevance.
What did Treisman argue against broadmann’s filter theory?
That it is not all or none, but rather it turns down input from unattended sources so we can still activate the meaning with the support of top down activation, but early filtering is an optional strategy rather than a fixed structural bottleneck.
Describe Treisman’s adapted model of filtering
Inputs are attended and unattended message
Sensory store -> attenuating -> higher level processing -> working memory
What is the difference between endogenous (voluntary, top down) and exogenous (stimulus driven, bottom up)?
Timing of this ‘exogenous’ cueing is different from endogenous.
Is visual selection as for auditory attention all or none?
there is a gradient of enhancement/suppression across the visual field. It is an optional process- the size of the attended area is under voluntary control
Summarise the process of visual attention
Processing of info in the visual field to the level of recognition and meaning is highly selective. The spot light of visual attention can be moved voluntarily to locations/objects of potential interest away from fixation. Size of the spotlight can be varied or zoomed and this selective filtering can occur early in the processing of visual info and processing of objects outside the spotlight is relatively shallow
