Psych202 - Foundations of cognitive neuroscience
Week 19 - Patrick
Lecture 15 - Attention
Whodunnit? Video
● Brain = highly selective on the stimuli you were paying attention to
● Salient stimulus = speech and no attention was paid to the visual stimulus
Overview
1. What is attention?
2. Effects of attention in the brain
3. Attentional control networks
What is attention?
Attention
● Definition:
○ Process by which the brain selects which sensory stimulus it will process at any given
moment
● Functional significance
○ Allows some information to enter the consciousness thus it maintains an incomplete picture
○ Hoffman (2019) - disadvantageous in evolution for the world to be represented as it is
○ Successful organisms process only a subset of stimuli and create representations of these
which are salient from the pov of survival and reproduction
○ Selective attention enables survival
Types of attention
● Reflexive attention (stimulus driven): bottom-up process where a sensory stimulus captures our
attention (the orienting reflex) - natural orientata
● Selective attention (task-driven): top-down ability to choose what to attend to - important to task
● Orienting: turning one’s attention to something
● Overt attention: orienting/turning with body
● Covert attention: no motor movements – hearing (switching attention between sound sources)
● Divided attention: ability to pay attention to more than one thing at a time
Effects of attention in the brain
Attention enhances brain responses
● Attending leads to higher activation of responding neurons
● Seen at all levels of observation:
1. Auditory and visual cortex
2. Subcortical stations
3. Non-invasive recordings
● Attention seems to reconfigure, temporarily, receptive fields in the sensory areas - the way sensory
areas analyse incoming signals
● Cortex operation is affected by attention
Early sensory processing affected by attention
● Auditory brainstem responses and mid-latency (20-50 ms) auditory ERPs
● Attention modulates cochlea function: otoacoustic emissions (OAEs) are affected by direction of
auditory attention
, ● Visual spatial attention expressed through eye movements (saccades) – in vision we clearly have
early selection
○ The retina produces a blurred image; only the central part is in focus; saccades shift the
focus of visual attention
Conditions in Attention research
Unattended message is lost. All participants can report is
the gender of the speaker.
Brain responses measured in two conditions: ATTEND
and UNATTEND.
Stimulation remains the same and only direction of
attention changes.
2nd Method:
● ACTIVE vs PASSIVE Active: Pay attention to sounds
● Passive: Ignore sounds / read a text / watch a video with sound turned off
● Problem with contrasting active to passive: You might be changing general arousal also.
● Therefore, dichotic listening is generally a good way to study attention – because only the focus of
attention is changed
Studying visual selective attention
FIGURE 7.17a Stimulus display used to reveal
physiological effects of sustained, spatial selective
attention.
The participant fixates the eyes on the central
crosshairs while stimuli are flashed to the left
(shown in figure) and right fields. (left panel) The
participant is instructed to covertly attend to the
left stimuli, and ignore those on the right. (right
panel) The participant is instructed to ignore the
left stimuli and attend to the right stimuli. Then the
responses to the same physical stimuli, such as
the white rectangle being flashed to left visual hemifield in the figure, are compared when they are attended
and ignored.
ERPs are enhanced by attention
Figure 2: Event-related potentials in a dichotic listening
task.
The solid line represents the idealized average voltage
response to an attended input over time; the dashed
line, the response to an unattended input. Hillyard and
colleagues found that the amplitude of the N1
component was enhanced when attending to the
stimulus compared to ignoring the stimulus.
Week 19 - Patrick
Lecture 15 - Attention
Whodunnit? Video
● Brain = highly selective on the stimuli you were paying attention to
● Salient stimulus = speech and no attention was paid to the visual stimulus
Overview
1. What is attention?
2. Effects of attention in the brain
3. Attentional control networks
What is attention?
Attention
● Definition:
○ Process by which the brain selects which sensory stimulus it will process at any given
moment
● Functional significance
○ Allows some information to enter the consciousness thus it maintains an incomplete picture
○ Hoffman (2019) - disadvantageous in evolution for the world to be represented as it is
○ Successful organisms process only a subset of stimuli and create representations of these
which are salient from the pov of survival and reproduction
○ Selective attention enables survival
Types of attention
● Reflexive attention (stimulus driven): bottom-up process where a sensory stimulus captures our
attention (the orienting reflex) - natural orientata
● Selective attention (task-driven): top-down ability to choose what to attend to - important to task
● Orienting: turning one’s attention to something
● Overt attention: orienting/turning with body
● Covert attention: no motor movements – hearing (switching attention between sound sources)
● Divided attention: ability to pay attention to more than one thing at a time
Effects of attention in the brain
Attention enhances brain responses
● Attending leads to higher activation of responding neurons
● Seen at all levels of observation:
1. Auditory and visual cortex
2. Subcortical stations
3. Non-invasive recordings
● Attention seems to reconfigure, temporarily, receptive fields in the sensory areas - the way sensory
areas analyse incoming signals
● Cortex operation is affected by attention
Early sensory processing affected by attention
● Auditory brainstem responses and mid-latency (20-50 ms) auditory ERPs
● Attention modulates cochlea function: otoacoustic emissions (OAEs) are affected by direction of
auditory attention
, ● Visual spatial attention expressed through eye movements (saccades) – in vision we clearly have
early selection
○ The retina produces a blurred image; only the central part is in focus; saccades shift the
focus of visual attention
Conditions in Attention research
Unattended message is lost. All participants can report is
the gender of the speaker.
Brain responses measured in two conditions: ATTEND
and UNATTEND.
Stimulation remains the same and only direction of
attention changes.
2nd Method:
● ACTIVE vs PASSIVE Active: Pay attention to sounds
● Passive: Ignore sounds / read a text / watch a video with sound turned off
● Problem with contrasting active to passive: You might be changing general arousal also.
● Therefore, dichotic listening is generally a good way to study attention – because only the focus of
attention is changed
Studying visual selective attention
FIGURE 7.17a Stimulus display used to reveal
physiological effects of sustained, spatial selective
attention.
The participant fixates the eyes on the central
crosshairs while stimuli are flashed to the left
(shown in figure) and right fields. (left panel) The
participant is instructed to covertly attend to the
left stimuli, and ignore those on the right. (right
panel) The participant is instructed to ignore the
left stimuli and attend to the right stimuli. Then the
responses to the same physical stimuli, such as
the white rectangle being flashed to left visual hemifield in the figure, are compared when they are attended
and ignored.
ERPs are enhanced by attention
Figure 2: Event-related potentials in a dichotic listening
task.
The solid line represents the idealized average voltage
response to an attended input over time; the dashed
line, the response to an unattended input. Hillyard and
colleagues found that the amplitude of the N1
component was enhanced when attending to the
stimulus compared to ignoring the stimulus.
