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Updated: Jun 7, 2026
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Optogenetic Entrainment of Hippocampal Theta Oscillations in Behaving Mice
Published on: June 29, 2018
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Precise spatial tuning of visually driven alpha oscillations in human visual cortex
Kenichi Yuasa1,2, Iris I A Groen1,3, Giovanni Piantoni4
1Department of Psychology, New York University, New York, United States.
Elife
|June 13, 2025
Summary
Alpha oscillations in the brain decrease with visual stimulation, contrary to some findings. This study reveals alpha power reduction and broadband power increase, crucial for understanding visual attention.
Area of Science:
- Neuroscience
- Visual Neuroscience
- Human Electrophysiology
Background:
- Alpha oscillations (approx. 10 Hz) are linked to occipital cortex inactivity.
- Recent studies show conflicting results regarding alpha power during visual stimulation.
Purpose of the Study:
- Investigate the relationship between alpha oscillations and visual stimuli using intracranial recordings.
- Hypothesize that increased local alpha power reflects a mix of reduced alpha and increased broadband power.
Main Methods:
- Used intracranial electrodes in human patients to record neural activity.
- Measured alpha oscillations and broadband power in response to visual stimuli.
- Developed a model to separate oscillatory and broadband power components.
- Applied population receptive field (pRF) models to both components.
Main Results:
- Alpha pRFs were larger than broadband pRFs but showed decreased alpha power within the receptive field.
- Broadband power increased with visual stimulation within the receptive field.
- Alpha suppression is precisely tuned and requires separating oscillatory from broadband signals.
Conclusions:
- Alpha oscillations are associated with cortical inactivity, evidenced by decreased power during stimulation.
- Separating alpha oscillatory power from broadband power is essential for accurate analysis.
- Large, negatively valenced alpha pRFs help explain exogenous visual attention mechanisms.
Keywords:
ECoGalpha oscillationscomputational modelsexogenous attentionhumanneurosciencepRFspopulation receptive fieldsvisual cortexMore Related Videos
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