Distortion of size perception in visuospatial neglect

Milner, A.D. and Harvey, M. (1995) Distortion of size perception in visuospatial neglect. Current Biology, 5(1), pp. 85-89. (doi: 10.1016/S0960-9822(95)00020-0)

Abstract

Background: A number of studies have shown that most patients with symptoms of unilateral (left-sided) visuospatial neglect make consistently rightward errors when attempting to bisect a horizontal line at its midpoint. One possible interpretation of this impairment is that such patients misperceive the left half of the line: that is, that they underestimate its extent relative to the right half.<p></p> Results We have carried out direct tests for such a perceptual distortion in three neglect patients by asking them to make matching judgements on pairs of horizontal rectangles, vertical rectangles or nonsense shapes, of varying relative size, presented on a computer screen. We report here that all of the patients tested showed a significant and substantial relative underestimation of the horizontal extent or area of stimuli presented on the left side of their egocentric space. There was no such misperception of vertical extent.<p></p> Conclusion It is suggested that size perception may be partially determined by a representational system that is anatomically centred in the parieto-temporal region of the brain. The results are interpreted in terms of damage to this system in neglect patients.<p></p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Harvey, Professor Monika
• Authors: Milner, A.D., and Harvey, M.
• College/School: College of Science and Engineering > School of Psychology
• Journal Name: Current Biology
• ISSN: 0960-9822
• ISSN (Online): 1879-0445