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Updated: Jul 28, 2026
13:51
Cross-Modal Multivariate Pattern Analysis
Published on: November 9, 2011
Two distinct modes of sensory processing observed in monkey primary visual cortex (V1)
H Supèr1, H Spekreijse, V A Lamme
1Graduate School of Neurosciences, Department of Visual System Analysis, AMC, University of Amsterdam, PO Box 12011, 1100 AA Amsterdam, The Netherlands.
Nature Neuroscience
|February 27, 2001
Summary
Neural activity in the primary visual cortex is suppressed when stimuli are missed. This suggests recurrent processing plays a key role in visual perception, bridging sensory input and decision-making.
Area of Science:
- Neuroscience
- Visual Perception
- Cognitive Neuroscience
Background:
- Sensory stimuli are not always perceived, even when salient.
- The neural mechanisms underlying missed perceptions remain unclear.
- Understanding these mechanisms is crucial for comprehending brain function.
Purpose of the Study:
- To investigate the neural basis of undetected sensory stimuli.
- To identify specific brain activity components that are suppressed during missed perceptions.
- To elucidate the role of recurrent processing in visual awareness.
Main Methods:
- Electrophysiological recordings in the primary visual cortex of monkeys.
- Analysis of neural activity components occurring after 100 ms.
- Correlation of neural activity with stimulus detection and non-detection.
Main Results:
- A late (> 100-ms) neural activity component in the primary visual cortex was selectively suppressed when stimuli were not perceived.
- Evidence suggests this suppressed activity relies on feedback from extrastriate areas.
- The perceptual level was identified as an intermediate stage between sensory processing and decision/motor stages.
Conclusions:
- Recurrent processing, involving feedback from higher-order areas, is critical for stimuli to reach a perceptual level.
- Suppression of late neural activity in the primary visual cortex underlies missed perceptions.
- Visual perception involves a distinct stage situated between sensory input and response execution.
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