Abstract
The brain is organized into distinct, flexible networks. Within these networks, cognitive variables such as attention can modulate sensory representations in accordance with moment-to-moment behavioral requirements. These modulations can be studied by varying task demands; however, the tasks employed are often incongruent with the postulated functions of a sensory system, limiting the characterization of the system in relation to natural behaviors. Here we combine domain-specific task manipulations and ultra-high field fMRI to study the nature of top-down modulations. We exploited faces, a visual category underpinned by a complex cortical network, and instructed participants to perform either a stimulus-relevant/domain-specific or a stimulus-irrelevant task in the scanner. We found that 1. perceptual ambiguity (i.e. difficulty of achieving a stable percept) is encoded in top-down modulations from higher-level cortices; 2. the right inferior-temporal lobe is active under challenging conditions and uniquely encodes trial-by-trial variability in face perception.
Original language | English (US) |
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Article number | 117654 |
Journal | NeuroImage |
Volume | 227 |
DOIs | |
State | Published - Feb 15 2021 |
Bibliographical note
Publisher Copyright:© 2020
Keywords
- Cognitive Neuroscience
- Cortical Network
- Perception
- Task modulations
- Top-down
- Ultra High Field
- Vision
- fMRI