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Updated: Jul 3, 2026
09:25
Detecting Pre-Stimulus Source-Level Effects on Object Perception with Magnetoencephalography
Published on: July 26, 2019
Spontaneous local variations in ongoing neural activity bias perceptual decisions
Guido Hesselmann1, Christian A Kell, Evelyn Eger
1Unité 562, Cognitive Neuroimaging, Institut National de la Santé et de la Recherche Médicale, 91191 Gif-sur-Yvette Cedex, France. g.hesselmann@gmail.com
Summary
Brain activity before a stimulus influences perception. Higher prestimulus activity in the fusiform face area predicted face perception, showing how neural fluctuations bias decisions.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Perception
Background:
- Neural variability in response to identical stimuli is linked to ongoing brain activity fluctuations.
- The perceptual consequences of these neural fluctuations are not well understood.
Purpose of the Study:
- To investigate the relationship between prestimulus neural activity and subsequent perceptual decisions.
- To understand how endogenous brain activity influences the interpretation of ambiguous visual stimuli.
Main Methods:
- Functional neuroimaging (fMRI) was used to record brain activity.
- Participants made perceptual decisions on an ambiguous figure (Rubin's vase-faces).
- Stimuli were presented at variable intervals (> or = 20 s).
Main Results:
- Prestimulus activity in the fusiform face area (FFA) was significantly higher when participants perceived faces versus the vase.
- This suggests that spontaneous variations in neural activity bias perceptual inference.
- Pre- and poststimulus activity interact nonlinearly, with prestimulus context shaping perceptual outcomes.
Conclusions:
- Endogenous prestimulus neural activity plays a crucial role in biasing perceptual decisions.
- The brain's ongoing activity influences how we interpret sensory information.
- Understanding neural variability is key to understanding perception and decision-making.
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