Looking left with left neglect: the role of spatial attention when active vision selects local image features for fixation

Ptak, Radek; Golay, Laetitia; Müri, René M; Schnider, Armin (2009). Looking left with left neglect: the role of spatial attention when active vision selects local image features for fixation. Cortex, 45(10), pp. 1156-66. Amsterdam: Elsevier 10.1016/j.cortex.2008.10.001

Full text not available from this repository. (Request a copy)

When we actively explore the visual environment, our gaze preferentially selects regions characterized by high contrast and high density of edges, suggesting that the guidance of eye movements during visual exploration is driven to a significant degree by perceptual characteristics of a scene. Converging findings suggest that the selection of the visual target for the upcoming saccade critically depends on a covert shift of spatial attention. However, it is unclear whether attention selects the location of the next fixation uniquely on the basis of global scene structure or additionally on local perceptual information. To investigate the role of spatial attention in scene processing, we examined eye fixation patterns of patients with spatial neglect during unconstrained exploration of natural images and compared these to healthy and brain-injured control participants. We computed luminance, colour, contrast, and edge information contained in image patches surrounding each fixation and evaluated whether they differed from randomly selected image patches. At the global level, neglect patients showed the characteristic ipsilesional shift of the distribution of their fixations. At the local level, patients with neglect and control participants fixated image regions in ipsilesional space that were closely similar with respect to their local feature content. In contrast, when directing their gaze to contralesional (impaired) space neglect patients fixated regions of significantly higher local luminance and lower edge content than controls. These results suggest that intact spatial attention is necessary for the active sampling of local feature content during scene perception.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Department of Head Organs and Neurology (DKNS) > Clinic of Neurology

UniBE Contributor:

Müri, René Martin

ISSN:

0010-9452

Publisher:

Elsevier

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 15:14

Last Modified:

04 May 2014 23:24

Publisher DOI:

10.1016/j.cortex.2008.10.001

PubMed ID:

19038381

Web of Science ID:

000270522000005

URI:

https://boris.unibe.ch/id/eprint/32631 (FactScience: 197888)

Actions (login required)

Edit item Edit item
Provide Feedback