Skip Navigation



Cerebral Cortex Advance Access published online on May 18, 2005
Cerebral Cortex, doi:10.1093/cercor/bhi111
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
16/3/337    most recent
bhi111v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Ptak, R.
Right arrow Articles by Schnider, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ptak, R.
Right arrow Articles by Schnider, A.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2005. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oupjournals.org

Article

Reflexive Orienting in Spatial Neglect Is Biased towards Behaviourally Salient Stimuli

Radek Ptak 1* and Armin Schnider 1

1 Division of Rehabilitation, University Hospital Geneva, 1211 Geneva 14, Switzerland

* To whom correspondence should be addressed.
Radek Ptak, E-mail: Radek.Ptak{at}hcuge.ch


  Abstract

Patients with spatial neglect are impaired when detecting contralesional targets presented shortly after an ipsilesional cue. This ‘disengagement’ deficit is believed to reflect reflexive orienting towards ipsilesional stimuli that is independent of behavioural goals. Here, we show that the extent of this spatial bias depends on the behavioural salience of ipsilesional stimuli. Healthy participants, brain-injured patients without neglect and neglect patients reacted to ipsilesional and contralesional visual targets. Prior to target presentation, a visual cue similar or dissimilar to the target was presented at target position or opposite the target. Although participants did not react to the similar cue, it had high behavioural salience since it shared features with the target stimulus. Neglect patients showed dramatically increased reaction times to contralesional targets, but only when these followed behaviourally relevant ipsilesional cues. No decrease of performance was observed with irrelevant cues. This performance pattern was not due to perceptual similarity, since the same effect was found when cue and target were semantically related but differed perceptually. Importantly, semantically related cues ceased to attract attention when they were defined as behaviourally irrelevant. These results show that neglect patients only orient attention reflexively towards ipsilesional stimuli with high behavioural salience.

Keywords: behavioural salience; parietal lobe; reflexive orienting; selective attention; spatial neglect.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 BrainHome page
R. Ptak, A. Schnider, L. Golay, and R. Muri
A non-spatial bias favouring fixated stimuli revealed in patients with spatial neglect
Brain, December 1, 2007; 130(12): 3211 - 3222.
[Abstract] [Full Text] [PDF]

Home page
 NeurologyHome page
G. Rode, P. Revol, Y. Rossetti, D. Boisson, and P. Bartolomeo
Looking while imagining: The influence of visual input on representational neglect
Neurology, February 6, 2007; 68(6): 432 - 437.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.