Perceptual processing in the ventral visual stream requires area TE but not rhinal cortex
- National Institute of Mental Health, National Institutes of Health, United States
- National Institute of Advanced Industrial Science and Technology (AIST), Japan
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, United States
Abstract
There is on-going debate over whether area TE, or the anatomically adjacent rhinal cortex, is the final stage of visual object processing. Both regions have been implicated in visual perception, but their involvement in non-perceptual functions, such as short-term memory, hinders clear-cut interpretation. Here using a two-interval forced choice task without a short-term memory demand, we find that after bilateral removal of area TE, monkeys trained to categorize images based on perceptual similarity (morphs between dogs and cats), are, on the initial viewing, badly impaired when given a new set of images. They improve markedly with a small amount of practice but nonetheless remain moderately impaired indefinitely. The monkeys with bilateral removal of rhinal cortex are, under all conditions, indistinguishable from unoperated controls. We conclude that the final stage of the integration of visual perceptual information into object percepts in the ventral visual stream occurs in area TE.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
National Institute of Mental Health (1ZIAMH002032-41)
- Mark A G Eldridge
- Narihisa Matsumoto
- John H Wittig
- Evan C Masseau
- Richard C Saunders
- Barry J Richmond
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental procedures conformed to the Institute of Medicine Guide for the Care and Use of Laboratory Animals and were performed under an Animal Study Protocol approved by the Animal Care and Use Committee of the National Institute of Mental Health, covered by project number: MH002032.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Perceptual processing in the ventral visual stream requires area TE but not rhinal cortex
eLife 7:e36310.
https://doi.org/10.7554/eLife.36310
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