Quenching of spontaneous fluctuations by attention in human visual cortex
| Autor: | Shany Grossman, Rotem Broday-Dvir, Edna Furman-Haran, Rafael Malach |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Adult Male Cognitive Neuroscience Rest Pupil diameter Sensory system Task (project management) 03 medical and health sciences Young Adult 0302 clinical medicine Attention network medicine Humans Attention Visual Cortex Brain Mapping Cognition Task engagement Human brain Magnetic Resonance Imaging 030104 developmental biology medicine.anatomical_structure Visual cortex Neurology Female Psychology Neuroscience 030217 neurology & neurosurgery Photic Stimulation |
| Zdroj: | NeuroImage. 171 |
| ISSN: | 1095-9572 |
| Popis: | In the absence of a task, the human brain enters a mode of slow spontaneous fluctuations. A fundamental, unresolved question is whether these fluctuations are ongoing and thus persist during task engagement, or alternatively, are quenched and replaced by task-related activations. Here, we examined this issue in the human visual cortex, using fMRI. Participants were asked to either perform a recognition task of randomly appearing face and non-face targets (attended condition) or watch them passively (unattended condition). Importantly, in approximately half of the trials, all sensory stimuli were absent. Our results show that even in the absence of stimuli, spontaneous fluctuations were suppressed by attention. The effect occurred in early visual cortex as well as in fronto-parietal attention network regions. During unattended trials, the activity fluctuations were negatively linked to pupil diameter, arguing against attentional fluctuations as underlying the effect. The results demonstrate that spontaneous fluctuations do not remain unchanged with task performance, but are rather modulated according to behavioral and cognitive demands. |
| Databáze: | OpenAIRE |
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