Simultanagnosia is a disorder of visual attention: the inability to see more than one object at one time. Some hypothesize that this is due to a constriction of the visual " window" of attention. Little is known about how simultanagnosics explore complex stimuli and how their behaviour changes with recovery. We monitored the eye movements of simultanagnosic patient SL to see how she scans social scenes shortly after onset of simultanagnosia (Time 1) and after some recovery (Time 2). At Time 1 SL had an abnormally low proportion of fixations to the eyes of the people in the scenes. She made a significantly larger proportion of fixations to the eyes at Time 2. We hypothesized that this change was related to an expansion of her restricted window of attention. Previously we simulated SL's behaviour in healthy subjects by having them view stimuli through a restricted viewing window. We used this simulation paradigm here to test our expanding window hypothesis. Subjects viewing social scenes through a larger window allocated more fixations to the eyes of people in the scenes than subjects viewing scenes through a smaller window, supporting our hypothesis. Recovery in simultanagnosia may be related to the expansion of the restricted attentional window that characterizes the disorder.
Bibliographical noteFunding Information:
KAD and EB were supported by the Natural Sciences and Engineering Research Council (NSERC), and the Michael Smith Foundation for Health Research (MSFHR). AK was supported by NSERC, a MSFHR Senior Scholar award, the Human Early Learning Partnership, and the Hampton Foundation. JJSB was supported by a Canada Research Chair and MSFHR Senior Scholarship. WFB was supported by NSERC. Thank you to SL for your time and dedication to this project.
Copyright 2011 Elsevier B.V., All rights reserved.
- Eye movements
- Parietal damage
- Social scene perception