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Updated: May 9, 2026
07:08
Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings
Published on: August 1, 2018
Representational dynamics of object vision: the first 1000 ms.
Thomas Carlson1, David A Tovar, Arjen Alink
1Department of Cognitive Sciences, Macquarie University, Sydney, NSW, Australia. thomas.carlson@mq.edu.au
Journal of Vision
|August 3, 2013
Summary
The brain hierarchically constructs object representations within 1000 milliseconds of visual processing. More abstract categories emerge later, suggesting flexible, time-varying neural codes for visual object recognition.
Area of Science:
- Cognitive Neuroscience
- Neuroimaging
- Visual Perception
Background:
- Human object recognition is efficient, with brain studies identifying representational spaces in the inferior temporal cortex.
- Previous research shows object exemplars are discriminable and cluster by category (e.g., faces, bodies).
Purpose of the Study:
- To investigate how object category structure emerges in the initial 1000 ms of visual processing.
- To understand the temporal dynamics of hierarchical category construction in the brain.
Main Methods:
- Magnetoencephalography (MEG) recorded brain activity from participants viewing 24 object exemplars across four hierarchical category levels.
- A sliding time window decoding approach was used to track object exemplar and category decoding over time.
Main Results:
- Object exemplar and category membership were decoded from neuromagnetic recordings within 100 ms of stimulus onset.
- Peak decodability latencies varied with category abstraction, with more abstract categories decoded later.
- Neural patterns encoding object category information were non-stationary and varied over time.
Conclusions:
- The brain hierarchically constructs object category representations, with abstract categories emerging later in processing.
- Flexible, time-varying neural codes may be employed by the brain to represent visual object categories.
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