A new no-report paradigm reveals that face cells encode both consciously perceived and suppressed stimuli.
Janis Karan Hesse, Doris Y Tsao
Elife November 11, 2020 DOI: 10.7554/elife.58360 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Rhesus macaque |
| Keywords | Binocular rivalry Consciousness Face patch Face perception Inferotemporal cortex No-report paradigm Rhesus macaque |
| Key findings | Large proportions of inferotemporal neurons represented the conscious percept even without active report, and both the conscious percept and suppressed stimulus could be decoded from single trials. |
Abstract
A powerful paradigm to identify neural correlates of consciousness is binocular rivalry, wherein a constant visual stimulus evokes a varying conscious percept. It has recently been suggested that activity modulations observed during rivalry may represent the act of report rather than the conscious percept itself. Here, we performed single-unit recordings from face patches in macaque inferotemporal (IT) cortex using a no-report paradigm in which the animal's conscious percept was inferred from eye movements. We found that large proportions of IT neurons represented the conscious percept even without active report. Furthermore, on single trials we could decode both the conscious percept and the suppressed stimulus. Together, these findings indicate that (1) IT cortex possesses a true neural correlate of consciousness and (2) this correlate consists of a population code wherein single cells multiplex representation of the conscious percept and veridical physical stimulus, rather than a subset of cells perfectly reflecting consciousness.