English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Psychophysical and fMRI measures of shape learning in the human visual cortex

Betts, L., Sarkheil, P., & Kourtzi, Z. (2003). Psychophysical and fMRI measures of shape learning in the human visual cortex. Poster presented at 33rd Annual Meeting of the Society for Neuroscience (Neuroscience 2003), New Orleans, LA, USA.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-0013-DAF9-6 Version Permalink: http://hdl.handle.net/21.11116/0000-0005-76D9-2
Genre: Poster

Files

show Files

Locators

show
hide
Description:
-

Creators

show
hide
 Creators:
Betts, LR1, 2, Author              
Sarkheil, P1, 2, 3, Author              
Kourtzi, Z1, 2, 3, Author              
Affiliations:
1Department Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497797              
2Max Planck Institute for Biological Cybernetics, Max Planck Society, Spemannstrasse 38, 72076 Tübingen, DE, ou_1497794              
3Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497798              

Content

show
hide
Free keywords: -
 Abstract: The aim of this study was to investigate the effect of learning in the integration of local elements into coherent visual shapes. Human early (V1, V2, VP, V4) and higher visual areas known to be involved in the analysis of shape information (Lateral Occipital Complex-LOC) have been implicated in the perceptual integration of global shapes. We used event-related fMRI to investigate the effect of learning in the neural representation of shapes across the human visual cortex. The stimuli consisted of symmetrical and asymmetrical closed contours rendered by aligned gabor elements and embedded in random gabor background fields. Two stimuli were presented simultaneously in each trial to the left and right of the fixation point and the subjects were instructed to report which stimulus contained the symmetrical contour. Behavioral and fMRI responses were recorded while observers performed the 2-AFC shape discrimination task in two different sessions, one before and one after three days of training. Observers were shown different sets of novel stimuli in every session and a set of training stimuli rendered in novel backgrounds across trials. Prior to training, no differences were observed in the behavioral performance or the fMRI responses across visual areas for the novel vs. the training stimulus set. However, after training the observers showed significantly improved accuracy in the discrimination task for learned vs. novel shapes. Consistently, fMRI responses in the early and the higher visual areas were significantly stronger for learned than novel stimuli. These results provide evidence for behavioral and neuronal learning-based plasticity in the human visual areas involved in coherent shape perception.

Details

show
hide
Language(s):
 Dates: 2003-11
 Publication Status: Published online
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: -
 Identifiers: BibTex Citekey: 3187
 Degree: -

Event

show
hide
Title: 33rd Annual Meeting of the Society for Neuroscience (Neuroscience 2003)
Place of Event: New Orleans, LA, USA
Start-/End Date: 2003-11-08 - 2003-11-12

Legal Case

show

Project information

show

Source 1

show
hide
Title: 33rd Annual Meeting of the Society for Neuroscience (Neuroscience 2003)
Source Genre: Proceedings
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: - Sequence Number: 819.16 Start / End Page: - Identifier: -