,Theories of Attention
Selective Filtering Models of Attention
Instance of both memory and attention
Focus has been in terms of limits on information processing
capacity
Broadbent (1952) & Cherry (1953)
Presented participants with dichotic tape recordings – different
spoken
messages presented to participants ears at the same time
Participants – attend one message (shadow or repeat the
material in one
ear) whilst ignoring another (unattended) message
Findings
Shadowing performance consistent, but failed to report much
information
from UA channel – could detect their own name, but no other
semantic
information
Broadbent’s Early Filter Model
Broadbent (1958)
Schematic model of how human mind might operate as it
receives stimuli
Incorporated findings from research
- Can not recall most of the unattended signal, could recall
recent few seconds
Indicated that brain temporarily retains information, but this
information
fades quickly
Large amount of information in the environment
- If we were to attend to everything, limited resources would
soon be
overloaded
Therefore, unattended material is deemed to be ‘filtered out’
This information is lost without reaching the level of awareness
Broadbent (1958)
Proposed the Early Filter Model to account for his and Cherry’s
results
Schematic – inspired by flow chart of computer science, popular
at the time complex program broken down into logical modules
Each module – takes on tasks or processing steps
2
, All sensory information – enters the attentional system –
reaches a bottleneck or filter
At this point the system chooses which message or visual
stimulus to processes further
Irrelevant information rejected by action of the filter –
anything that is not task relevant – rejected entry into the
attentional system
Broadbent – filter is place directly after the sensory store
(visual or auditory) hence the term – early filter model
Filter – function based on physical characteristics –
- motion, colour, shape and spatial location (visual modality)
- pitch, loudness & spatial location (auditory modality)
Cherry (1953) – results consistent with Broadbent’s Early
Filter model
Cherry – participants only detected physical changes in
unattended input (e.g. changes in voice from male/female or
changes from speech to tone).
Participants failed to notice changes in semantic
characteristics, and could not recall the main gist of the
unattended message
As Broadbent predicted – irrelevant info, filtered out prior to
deeper processing
Modifications to Broadbent’s Model
Treisman – played two different message to two ears –
logical content was confused
- Left ear - “if you are creaming butter and piccolos, clarinets,
and tubes seldom play solos”
- Right ear – “Many orchestral instruments such as sugar, it’s a
good idea to use a slow speed mixer”
Participants were instructed to shadow the message
presented in the right ear – most switch channels to follow
logical meaning of the sentence
According to Broadbent – should not be possible as irrelevant
information – not being attended therefore no analysis of
meaning takes place
Treisman’s Attenuation Model
Treisman (1964) forwarded the Attenuation Model in order
to explain these results
Assumed that certain messages are attended to as a result of
their semantic content
3
Selective Filtering Models of Attention
Instance of both memory and attention
Focus has been in terms of limits on information processing
capacity
Broadbent (1952) & Cherry (1953)
Presented participants with dichotic tape recordings – different
spoken
messages presented to participants ears at the same time
Participants – attend one message (shadow or repeat the
material in one
ear) whilst ignoring another (unattended) message
Findings
Shadowing performance consistent, but failed to report much
information
from UA channel – could detect their own name, but no other
semantic
information
Broadbent’s Early Filter Model
Broadbent (1958)
Schematic model of how human mind might operate as it
receives stimuli
Incorporated findings from research
- Can not recall most of the unattended signal, could recall
recent few seconds
Indicated that brain temporarily retains information, but this
information
fades quickly
Large amount of information in the environment
- If we were to attend to everything, limited resources would
soon be
overloaded
Therefore, unattended material is deemed to be ‘filtered out’
This information is lost without reaching the level of awareness
Broadbent (1958)
Proposed the Early Filter Model to account for his and Cherry’s
results
Schematic – inspired by flow chart of computer science, popular
at the time complex program broken down into logical modules
Each module – takes on tasks or processing steps
2
, All sensory information – enters the attentional system –
reaches a bottleneck or filter
At this point the system chooses which message or visual
stimulus to processes further
Irrelevant information rejected by action of the filter –
anything that is not task relevant – rejected entry into the
attentional system
Broadbent – filter is place directly after the sensory store
(visual or auditory) hence the term – early filter model
Filter – function based on physical characteristics –
- motion, colour, shape and spatial location (visual modality)
- pitch, loudness & spatial location (auditory modality)
Cherry (1953) – results consistent with Broadbent’s Early
Filter model
Cherry – participants only detected physical changes in
unattended input (e.g. changes in voice from male/female or
changes from speech to tone).
Participants failed to notice changes in semantic
characteristics, and could not recall the main gist of the
unattended message
As Broadbent predicted – irrelevant info, filtered out prior to
deeper processing
Modifications to Broadbent’s Model
Treisman – played two different message to two ears –
logical content was confused
- Left ear - “if you are creaming butter and piccolos, clarinets,
and tubes seldom play solos”
- Right ear – “Many orchestral instruments such as sugar, it’s a
good idea to use a slow speed mixer”
Participants were instructed to shadow the message
presented in the right ear – most switch channels to follow
logical meaning of the sentence
According to Broadbent – should not be possible as irrelevant
information – not being attended therefore no analysis of
meaning takes place
Treisman’s Attenuation Model
Treisman (1964) forwarded the Attenuation Model in order
to explain these results
Assumed that certain messages are attended to as a result of
their semantic content
3
