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Updated: Apr 23, 2026
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Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings
Published on: August 1, 2018
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Investigating category- and shape-selective neural processing in ventral and dorsal visual stream under interocular
Karin Ludwig1, Norbert Kathmann, Philipp Sterzer
1Visual Perception Laboratory, Department of Psychiatry and Psychotherapy, Campus Charité Mitte, Charité - Universitätsmedizin Berlin, Berlin, Germany; Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany.
Human Brain Mapping
|October 2, 2014
Summary
Action processing in the dorsal visual stream is not exclusively preserved under continuous flash suppression (CFS). Shape-selective processing occurs in both dorsal and ventral streams, challenging the "vision-for-action" theory.
Area of Science:
- Neuroscience
- Visual Perception
- Cognitive Psychology
Background:
- The dual-stream theory proposes distinct visual pathways for perception and action.
- Continuous flash suppression (CFS) studies suggest dorsal stream processing may bypass awareness.
- It's debated whether this dorsal processing is shape- or action-specific.
Purpose of the Study:
- To investigate category- and shape-selective responses in dorsal and ventral visual streams under CFS.
- To determine if tool stimuli processing under CFS is due to shape or action representation.
- To examine if suppression depth differentially affects dorsal and ventral stream activity.
Main Methods:
- Used functional magnetic resonance imaging (fMRI) with blood-oxygen-level-dependent (BOLD) responses.
- Employed multivariate pattern analysis (MVPA) to decode stimuli.
- Presented images of faces and tools under varying CFS mask contrasts.
Main Results:
- Decoding of elongated tools was enhanced in both ventral and dorsal streams.
- Shape-selective processing was observed in both visual streams under CFS.
- No differential modulation of category-selective activity by suppression depth was found.
Conclusions:
- Findings support shape-selective processing in both dorsal and ventral streams under CFS.
- The data do not exclusively support dorsal stream "vision-for-action" preservation under suppression.
- Action-related processing under CFS is not solely confined to the dorsal visual stream.
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