Attention Flashcards
What are the 6 types of attention?
- Reflexive Attention (stimulus-driven)
- Selective Attention (task-driven)
- Orienting
- Overt Attention
- Covert Attention
- Divided Attention
What is “Reflexive Attention (stimulus-driven)?
Bottom-up processes where a sensory stimulus captures our attention (the orienting reflex)
What is “Selective Attention (task-driven)?
Top-down ability to choose what to attend to
How can you study Visual Selective Attention?
A participant fixates on the central cross, while stimuli are flashed to the left and right fields. Instructed to covertly attend to left field and ignore the right and vice versa. Then response to the same stimuli on the left visual hemisphere are compared when they are attended and ignored.
What is “Orienting Attention”?
Turning one’s attention to something
What is “Overt Attention”?
Orienting with body
What is “Covert Attention”?
No motor movements
What is “Divided Attention”?
Process different pieces of information simultaneously
What are the four conditions in attention?
- Attend
- Unattend
- Active
- Passive
What is the difference between Attended and Unattended conditions?
If one message is attended and the other is unattended, only the attended is remembered. Unattended is lost and all participants can report is the gender of the speaker.
What is the difference between Active and Passive conditions?
Active: Pay attention to sounds
Passive: Ignore sounds/read a text/watch a video with sound turned off.
What is the 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.
What 3 levels of observation show that attending to a stimulus leads to higher activation of those neurons?
- In auditory and visual cortex
- In subcortical stations (cochlea, midbrain & thalamus)
- In non-invasive recordings (EEG, MEG, fMRI) & single-cell recordings
How does attention change responses?
It enhances and reconfigures, temporarily, receptive fields in the sensory areas
Describe a study on ERPs being enhanced by attention (Hillyard et al.):
(See Attention Lecture, Slide 13 for graph) The solid line represents the idealized average voltage response to an attended input over time, the dashed line represents the response to an unattended input. The amplitude of the N1 component was enhanced when attending to the stimulus compared to ignoring the stimulus.
Who studied intracortical recordings from cortex?
Mesgarani & Chang (2012)
How did Mesgarani & Chang (2012) study intracortical recordings from the cortex?
- Presented sentences to human epilepsy patients
- Took intracortical recordings from surface of human auditory cortex
- Method: Stimulus spectrogram reconstruction from neural population
- Responses: Measure neuronal activity and deduce what the stimulus was
What were the conditions of Mesgarani & Chang’s (2012) study?
- First auditory stimulus only, first being attended to
- Second auditory stimulus only, second being attended to
- Both auditory stimuli, first being attended to
- Both auditory stimuli, second being attended to
(In mixed condition, auditory cortex is responding as if the sentence being attended to is being presented alone)
Who studied Attention Modulates Visual Cortex?
Hopfinger et al (2000)
Describe Hopfinger et al’s (2000) study:
- fMRI study
- Attending to the left or right visual hemifield leads to increased activation in visual cortex of the contralateral hemisphere
- No effect in primary visual cortex (V1)
(Selective Visual Attention: Before the target is delivered to the dorsal frontoparietal network, attention also activates the visual cortex.)
What parts of the brain control attention?
The cortex and midbrain
Where is the midbrain located?
It sits on top of the brainstem, under the cortex.
What part of the brain controls selective attention during complex behaviour?
Frontoparietal network (prefrontal and posterior parietal cortex)
What does a midbrain network direct for surprising or highly salient stimuli which have a spatial location?
Directs spatial attention and gaze to stimulus location
