Problem 1
Inattentional blindness Failures of Awareness: The Case of Inattentional Blindness
- Inattentional blindness Failure to notice unexpected objects or events when
attention is focused elsewhere failure of awareness
- Our perception of the world is limited
o Process only one stream of information at a time filtering other information
from awareness perceive only what receives our attention
- Dichotic listening
o It is a selective listening task
▪ Selective listening method for studying selective attention
people focus attention on one auditory stream of information while
ignoring other auditory information
o A set of headphones play two completely different speech streams one to
each ear
▪ Task monitor one stream while ignoring the other attention
demanding task
▪ Result you are deaf to the substance of the ignored speech
won’t notice if the speaker in your right ear switches to a different
language, is replaced by a different speaker with a similar voice or the
content of their speech becomes nonsensical
● A form of cognitive deafness due to the nature of focused,
selective attention
● Still some of limited attention to the ignored speech stream
notice big changes
o Power of attention to filter extraneous information from awareness while
letting in elements that we want to hear
- Visual analogue of the dichotic listening task
o Participants were asked to monitor one of the events failed to notice
unexpected events in the ignored video stream
▪ Unaware of events happening outside the focus of their attention
- Selective attention can induce to failures of awareness
o A variant count passes in two teams wearing different shirt color
▪ Miss the umbrella women that passes through
- Counterintuitive findings the displays had an odd, ghostly appearance so
researchers dismissed their implications
o Replication of Neisser´s work findings were the same many people
missed the umbrella woman when all of the actors in the video were partially
transparent and occupying the same space
▪ Added another thing teams filmed with a single camera fully
visible
● Still half the observers missed the gorilla example of
inattentional blindness a failure of awareness
- Factors that cause people to miss unexpected events + situations in which
inattentional blindness occurs
o Shared features
, ▪ People are much more likely to notice unexpected objects that share
features with the attended items in a display
● Example more likely to notice the gorilla if you were
counting the passes of the team wearing black
● However unique items can go unnoticed
o Effort into the attention – demanding task
▪ Effort you put into the attention-demanding task more attention
demanding = less likely to notice the gorilla
● Due to the limited cognitive resources limits on the capacity
of attention without attention to the unexpected event you
won´t be aware of it
- Inattentional blindness in real world
o Police officer claimed not to have seen a brutal beating while chasing a murder
suspect
▪ Experiment replicating this case
● At night 65% missed the fight and 44% in broad day light
o Auditory distractions can induce real-world failures to see (inattentional
blindness)
▪ Decreases situation awareness increases the chances that people
will miss something important
- Inattentional deafness
o The auditory analog of inattentional blindness
▪ People fail to notice an unexpected sound or voice when attention is
devoted to other aspects
o When listening to a set of spatially localized conversations over headphones
fail to notice a person walking through the scene stating “I am a gorilla”
▪ Focused attention makes us see and hear way less of the unattended
information than we think
● Focused attention affects the detection of unexpected objects
falling outside that focus
- The more like the ignored elements of a scene the less likely people are to notice
- The more distracted we are the less likely we are to be aware of our surroundings
o Under conditions of distraction we develop tunnel vision
- Individual factors
o People who have a greater working memory capacity more likely to notice
unexpected objects
▪ More resources available when focusing attention more likely to
spot other aspects of their world
▪ Controversial other studies find no such relationship
o Theoretical reasons to predict each pattern
▪ With more resources available people should be more likely to
notice
● However people with greater working memory capacity
better able to maintain their focus on their prescribed task
= they should be less likely to notice
o The ability to perform a task does not predict the likelihood of noticing
, - These findings run counter our intuitions counterintuitive
o We think we see and remember far more of our surroundings than we actually
do that is what makes it counterintuitive
o Why do we have a mistaken intuition?
▪ Our experiences mislead us
● Rarely forced to confront something that we missed
unaware of what we have missed but fully aware of those
elements of a scene that we have noticed we assume our
experiences are representative of the state of the world
Selective attention
- Cocktail party problem
o Process of tracking one conversation in the face of the distraction of other
conversations
- Shadowing
o Task to study selective attention in which you listen to two different
messages
▪ Dichotic presentation separate message to each ear
● Repeat back only one of the messages as soon as possible
after you hear it follow just one message
▪ Shadowing required a significant amount of concentration but
participants were quite successful in shadowing distinct messages in
dichotic-listening tasks
● They notice physical, sensory changes in the unattended
message but not a language shift or when the message is
presented backwards
o When their name was presented switch attention
to their name
▪ Those who hear their name in the unattended
message have limited working-memory
capacity easily distracted –or not?...
- Factors that help you selectively attend only to the message of the target speaker
o Distinctive sensory characteristics of the target’s speech
▪ Example high vs. low pitch, pace, etc.
o Sound intensity loudness
o Location of the sound source
▪ Spatial cues are less important than factors like how harmonious and
rhythmic the target sounds
Theories of selective attention
- Filter theories and bottleneck theories
o Filter blocks some of the information going through and thereby selects
only a part of the total of information to pass through to the next stage
o Bottleneck slows down information passing through
- Broadbent´s Model
o Filter information right after we notice it at the sensory level
, o Multiple channels of sensory input reach an attentional filter
▪ The filter permits only one channel of sensory information to proceed
and reach the processes of perception that is when we assign
meaning to our perception
▪ Other stimuli filtered out at the sensory level and may never reach
the level of perception
▪ Sensory information sometimes may be noticed by an unattended ear
if it does not have to be processed elaborately
● Information requiring higher perceptual processes is not
noticed if not attended to
- Selective Filter Model (Moray)
o Even when participants ignore most other high-level aspects of an unattended
message they recognize their names Broadbent´s model must be wrong
▪ Messages that are of high importance may break through the filter of
selective attention
● Selective filter blocks out most information at the sensory
level some personally important messages burst through
the filtering mechanism
- Attenuation Model (Treisman)
o Experiment participants shadowing coherent messages at some point
switched the remainder of the coherent message from the attended to the
unattended ear they had been somehow processing the content of the
unattended message
o Findings suggested that at least some information about unattended signals is
being analyzed
▪ Theory of selective attention that involves a later filtering mechanism
● Instead of blocking stimuli out filter merely attenuates the
strength of stimuli other than the target stimulus
o When the stimuli reach us we analyze them at a low
level for target properties like loudness and pitch
o If the stimuli possess those target properties we
pass the signal on to the next stage
o If they do not we pass on a weakened version of the
stimulus
● Then perceptually analyze the meaning of the stimuli and
their relevance to us message from the unattended ear can
come into consciousness and influence our subsequent
actions
- Late – Filter Model (Deutsch and Deutsch)
o The location of the filter is even later
▪ Stimuli are filtered out only after they have been analyzed for their
physical properties and their meaning people would be able to
recognize information entering the unattended ear
▪ Recognize their names or a translation of what they hear on the
attended ear
Inattentional blindness Failures of Awareness: The Case of Inattentional Blindness
- Inattentional blindness Failure to notice unexpected objects or events when
attention is focused elsewhere failure of awareness
- Our perception of the world is limited
o Process only one stream of information at a time filtering other information
from awareness perceive only what receives our attention
- Dichotic listening
o It is a selective listening task
▪ Selective listening method for studying selective attention
people focus attention on one auditory stream of information while
ignoring other auditory information
o A set of headphones play two completely different speech streams one to
each ear
▪ Task monitor one stream while ignoring the other attention
demanding task
▪ Result you are deaf to the substance of the ignored speech
won’t notice if the speaker in your right ear switches to a different
language, is replaced by a different speaker with a similar voice or the
content of their speech becomes nonsensical
● A form of cognitive deafness due to the nature of focused,
selective attention
● Still some of limited attention to the ignored speech stream
notice big changes
o Power of attention to filter extraneous information from awareness while
letting in elements that we want to hear
- Visual analogue of the dichotic listening task
o Participants were asked to monitor one of the events failed to notice
unexpected events in the ignored video stream
▪ Unaware of events happening outside the focus of their attention
- Selective attention can induce to failures of awareness
o A variant count passes in two teams wearing different shirt color
▪ Miss the umbrella women that passes through
- Counterintuitive findings the displays had an odd, ghostly appearance so
researchers dismissed their implications
o Replication of Neisser´s work findings were the same many people
missed the umbrella woman when all of the actors in the video were partially
transparent and occupying the same space
▪ Added another thing teams filmed with a single camera fully
visible
● Still half the observers missed the gorilla example of
inattentional blindness a failure of awareness
- Factors that cause people to miss unexpected events + situations in which
inattentional blindness occurs
o Shared features
, ▪ People are much more likely to notice unexpected objects that share
features with the attended items in a display
● Example more likely to notice the gorilla if you were
counting the passes of the team wearing black
● However unique items can go unnoticed
o Effort into the attention – demanding task
▪ Effort you put into the attention-demanding task more attention
demanding = less likely to notice the gorilla
● Due to the limited cognitive resources limits on the capacity
of attention without attention to the unexpected event you
won´t be aware of it
- Inattentional blindness in real world
o Police officer claimed not to have seen a brutal beating while chasing a murder
suspect
▪ Experiment replicating this case
● At night 65% missed the fight and 44% in broad day light
o Auditory distractions can induce real-world failures to see (inattentional
blindness)
▪ Decreases situation awareness increases the chances that people
will miss something important
- Inattentional deafness
o The auditory analog of inattentional blindness
▪ People fail to notice an unexpected sound or voice when attention is
devoted to other aspects
o When listening to a set of spatially localized conversations over headphones
fail to notice a person walking through the scene stating “I am a gorilla”
▪ Focused attention makes us see and hear way less of the unattended
information than we think
● Focused attention affects the detection of unexpected objects
falling outside that focus
- The more like the ignored elements of a scene the less likely people are to notice
- The more distracted we are the less likely we are to be aware of our surroundings
o Under conditions of distraction we develop tunnel vision
- Individual factors
o People who have a greater working memory capacity more likely to notice
unexpected objects
▪ More resources available when focusing attention more likely to
spot other aspects of their world
▪ Controversial other studies find no such relationship
o Theoretical reasons to predict each pattern
▪ With more resources available people should be more likely to
notice
● However people with greater working memory capacity
better able to maintain their focus on their prescribed task
= they should be less likely to notice
o The ability to perform a task does not predict the likelihood of noticing
, - These findings run counter our intuitions counterintuitive
o We think we see and remember far more of our surroundings than we actually
do that is what makes it counterintuitive
o Why do we have a mistaken intuition?
▪ Our experiences mislead us
● Rarely forced to confront something that we missed
unaware of what we have missed but fully aware of those
elements of a scene that we have noticed we assume our
experiences are representative of the state of the world
Selective attention
- Cocktail party problem
o Process of tracking one conversation in the face of the distraction of other
conversations
- Shadowing
o Task to study selective attention in which you listen to two different
messages
▪ Dichotic presentation separate message to each ear
● Repeat back only one of the messages as soon as possible
after you hear it follow just one message
▪ Shadowing required a significant amount of concentration but
participants were quite successful in shadowing distinct messages in
dichotic-listening tasks
● They notice physical, sensory changes in the unattended
message but not a language shift or when the message is
presented backwards
o When their name was presented switch attention
to their name
▪ Those who hear their name in the unattended
message have limited working-memory
capacity easily distracted –or not?...
- Factors that help you selectively attend only to the message of the target speaker
o Distinctive sensory characteristics of the target’s speech
▪ Example high vs. low pitch, pace, etc.
o Sound intensity loudness
o Location of the sound source
▪ Spatial cues are less important than factors like how harmonious and
rhythmic the target sounds
Theories of selective attention
- Filter theories and bottleneck theories
o Filter blocks some of the information going through and thereby selects
only a part of the total of information to pass through to the next stage
o Bottleneck slows down information passing through
- Broadbent´s Model
o Filter information right after we notice it at the sensory level
, o Multiple channels of sensory input reach an attentional filter
▪ The filter permits only one channel of sensory information to proceed
and reach the processes of perception that is when we assign
meaning to our perception
▪ Other stimuli filtered out at the sensory level and may never reach
the level of perception
▪ Sensory information sometimes may be noticed by an unattended ear
if it does not have to be processed elaborately
● Information requiring higher perceptual processes is not
noticed if not attended to
- Selective Filter Model (Moray)
o Even when participants ignore most other high-level aspects of an unattended
message they recognize their names Broadbent´s model must be wrong
▪ Messages that are of high importance may break through the filter of
selective attention
● Selective filter blocks out most information at the sensory
level some personally important messages burst through
the filtering mechanism
- Attenuation Model (Treisman)
o Experiment participants shadowing coherent messages at some point
switched the remainder of the coherent message from the attended to the
unattended ear they had been somehow processing the content of the
unattended message
o Findings suggested that at least some information about unattended signals is
being analyzed
▪ Theory of selective attention that involves a later filtering mechanism
● Instead of blocking stimuli out filter merely attenuates the
strength of stimuli other than the target stimulus
o When the stimuli reach us we analyze them at a low
level for target properties like loudness and pitch
o If the stimuli possess those target properties we
pass the signal on to the next stage
o If they do not we pass on a weakened version of the
stimulus
● Then perceptually analyze the meaning of the stimuli and
their relevance to us message from the unattended ear can
come into consciousness and influence our subsequent
actions
- Late – Filter Model (Deutsch and Deutsch)
o The location of the filter is even later
▪ Stimuli are filtered out only after they have been analyzed for their
physical properties and their meaning people would be able to
recognize information entering the unattended ear
▪ Recognize their names or a translation of what they hear on the
attended ear
