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Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity
Published on: March 18, 2019
Dissociating vision and visual attention in the human pulvinar
A T Smith1, P L Cotton, A Bruno
1Department of Psychology, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, UK. a.t.smith@rhul.ac.uk
Journal of Neurophysiology
|December 17, 2008
Summary
The human pulvinar activates with visual stimuli even without attention. Attentional enhancement of pulvinar activity is modest, matching cortical responses.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Neuroimaging
Background:
- The pulvinar, a thalamic region, is implicated in attention control.
- Its precise functions in humans and primates are not fully understood.
Purpose of the Study:
- To investigate the roles of visual drive and covert spatial attention in activating the human posterior pulvinar.
- To characterize the functional organization of the posterior pulvinar.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used in an event-related design.
- Participants covertly attended to large optic flow stimuli presented to the left and/or right of fixation.
- Activity was measured in response to attended and unattended stimuli.
Main Results:
- Unattended visual stimuli robustly activated medial and dorsal regions of the posterior pulvinar.
- These activations showed a strong contralateral bias, suggesting retinotopic organization.
- Attending to the stimulus enhanced pulvinar response by approximately 20%.
Conclusions:
- Visual drive is sufficient to activate the human posterior pulvinar; attention is not strictly necessary.
- The degree of attentional enhancement in the pulvinar is comparable to that in connected cortical areas.
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