Perceptual learning via modification of cortical top-down signals.
The primary visual cortex (V1) is pre-wired to facilitate the extraction of behaviorally important visual features. Collinear edge detectors in V1, for instance, mutually enhance each other to improve the perception of lines against a noisy background. The same pre-wiring that facilitates line extra...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2007-08-01
|
| Series: | PLoS Computational Biology |
| Online Access: | http://europepmc.org/articles/PMC1950342?pdf=render |
| _version_ | 1818585138500468736 |
|---|---|
| author | Roland Schäfer Eleni Vasilaki Walter Senn |
| author_facet | Roland Schäfer Eleni Vasilaki Walter Senn |
| author_sort | Roland Schäfer |
| collection | DOAJ |
| description | The primary visual cortex (V1) is pre-wired to facilitate the extraction of behaviorally important visual features. Collinear edge detectors in V1, for instance, mutually enhance each other to improve the perception of lines against a noisy background. The same pre-wiring that facilitates line extraction, however, is detrimental when subjects have to discriminate the brightness of different line segments. How is it possible to improve in one task by unsupervised practicing, without getting worse in the other task? The classical view of perceptual learning is that practicing modulates the feedforward input stream through synaptic modifications onto or within V1. However, any rewiring of V1 would deteriorate other perceptual abilities different from the trained one. We propose a general neuronal model showing that perceptual learning can modulate top-down input to V1 in a task-specific way while feedforward and lateral pathways remain intact. Consistent with biological data, the model explains how context-dependent brightness discrimination is improved by a top-down recruitment of recurrent inhibition and a top-down induced increase of the neuronal gain within V1. Both the top-down modulation of inhibition and of neuronal gain are suggested to be universal features of cortical microcircuits which enable perceptual learning. |
| first_indexed | 2024-12-16T08:32:18Z |
| format | Article |
| id | doaj.art-86685cc953a44a6b9c68d949b6b44eda |
| institution | Directory Open Access Journal |
| issn | 1553-734X 1553-7358 |
| language | English |
| last_indexed | 2024-12-16T08:32:18Z |
| publishDate | 2007-08-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Computational Biology |
| spelling | doaj.art-86685cc953a44a6b9c68d949b6b44eda2022-12-21T22:37:52ZengPublic Library of Science (PLoS)PLoS Computational Biology1553-734X1553-73582007-08-0138e16510.1371/journal.pcbi.0030165Perceptual learning via modification of cortical top-down signals.Roland SchäferEleni VasilakiWalter SennThe primary visual cortex (V1) is pre-wired to facilitate the extraction of behaviorally important visual features. Collinear edge detectors in V1, for instance, mutually enhance each other to improve the perception of lines against a noisy background. The same pre-wiring that facilitates line extraction, however, is detrimental when subjects have to discriminate the brightness of different line segments. How is it possible to improve in one task by unsupervised practicing, without getting worse in the other task? The classical view of perceptual learning is that practicing modulates the feedforward input stream through synaptic modifications onto or within V1. However, any rewiring of V1 would deteriorate other perceptual abilities different from the trained one. We propose a general neuronal model showing that perceptual learning can modulate top-down input to V1 in a task-specific way while feedforward and lateral pathways remain intact. Consistent with biological data, the model explains how context-dependent brightness discrimination is improved by a top-down recruitment of recurrent inhibition and a top-down induced increase of the neuronal gain within V1. Both the top-down modulation of inhibition and of neuronal gain are suggested to be universal features of cortical microcircuits which enable perceptual learning.http://europepmc.org/articles/PMC1950342?pdf=render |
| spellingShingle | Roland Schäfer Eleni Vasilaki Walter Senn Perceptual learning via modification of cortical top-down signals. PLoS Computational Biology |
| title | Perceptual learning via modification of cortical top-down signals. |
| title_full | Perceptual learning via modification of cortical top-down signals. |
| title_fullStr | Perceptual learning via modification of cortical top-down signals. |
| title_full_unstemmed | Perceptual learning via modification of cortical top-down signals. |
| title_short | Perceptual learning via modification of cortical top-down signals. |
| title_sort | perceptual learning via modification of cortical top down signals |
| url | http://europepmc.org/articles/PMC1950342?pdf=render |
| work_keys_str_mv | AT rolandschafer perceptuallearningviamodificationofcorticaltopdownsignals AT elenivasilaki perceptuallearningviamodificationofcorticaltopdownsignals AT waltersenn perceptuallearningviamodificationofcorticaltopdownsignals |