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Updated: Jun 4, 2026
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Creating Objects and Object Categories for Studying Perception and Perceptual Learning
Published on: November 2, 2012
Recurrent processing in V1/V2 contributes to categorization of natural scenes
Mika Koivisto1, Henry Railo, Antti Revonsuo
1Centre for Cognitive Neuroscience and Department of Psychology, University of Turku, 20014 Turku, Finland. mika.koivisto@utu.fi
Summary
Recurrent interactions in the visual cortex, not just feedforward processing, are crucial for rapidly categorizing natural scenes. This study highlights the role of early visual areas (V1/V2) in visual perception.
Area of Science:
- Neuroscience
- Cognitive Science
- Visual Perception
Background:
- Ultra-rapid categorization of natural scenes is often attributed to feedforward processing in ventral brain areas.
- Emerging theories emphasize the significant role of rapid recurrent interactions within the visual cortex.
Purpose of the Study:
- To investigate the causal role of recurrent processing in natural scene categorization.
- To determine the contributions of early visual cortex (V1/V2) and lateral occipital cortex (LO) to this process.
Main Methods:
- fMRI-guided transcranial magnetic stimulation (TMS) was applied to V1/V2 and LO in human participants.
- Participants performed a rapid categorization task, identifying images containing animals.
Main Results:
- V1/V2 demonstrated a significant contribution to both categorization speed and subjective perception.
- The influence of V1/V2 occurred throughout a prolonged period, encompassing and extending beyond the activity window of LO.
- LO's contribution to categorization was observed later than that of V1/V2.
Conclusions:
- Recurrent interactions within the visual cortex, particularly involving early visual areas like V1/V2, play a causal role in the rapid categorization and perception of natural scenes.
- These findings challenge purely feedforward models and underscore the dynamic, interactive nature of visual processing.
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