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Updated: Jun 24, 2026
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Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings
Published on: August 1, 2018
Visual adaptation to convexity in macaque area V4
K-M Müller1, M Wilke, D A Leopold
1Unit on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Building 49, Room B2J-45 MSC 4400, 49 Convent Drive, Bethesda, MD 20892, USA.
Neuroscience
|April 7, 2009
Summary
Neural adaptation to shape stimuli causes aftereffects, perceptual illusions. Neurons in the V4 area of monkey brains shift their tuning, contributing to these shape aftereffects and influencing convexity perception.
Area of Science:
- Neuroscience
- Visual Perception
- Computational Neuroscience
Background:
- Aftereffects are perceptual illusions resulting from visual adaptation.
- Neurophysiological studies link adaptation to reduced neural firing rates and altered tuning.
- Shape adaptation, specifically to convexity, can distort subsequent shape perception.
Purpose of the Study:
- Investigate the role of V4 neurons in shape-specific adaptation.
- Determine if V4 neuronal responses contribute to the convexity aftereffect.
Main Methods:
- Monitored visually responsive neurons in rhesus monkeys' V4 area.
- Presented simple shapes varying in convexity after adaptation to convex or concave stimuli.
- Recorded neuronal responses to assess tuning shifts and adaptation effects.
Main Results:
- Adaptation shifted neuronal tuning away from the adapter stimulus.
- Neuronal responses to neutral shapes shifted towards the opposite convexity.
- Observed both nonspecific and stimulus-specific decreases in neuronal response magnitude.
Conclusions:
- V4 neurons exhibit shape-specific adaptation.
- These neuronal adaptations in V4 likely contribute to the perception of convexity aftereffects.
- Findings provide a neural basis for shape-specific visual adaptation.
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