The influence of viewing eye on pseudoneglect magnitude

Citation
Me. Mccourt et al., The influence of viewing eye on pseudoneglect magnitude, J INT NEURO, 7(3), 2001, pp. 391-395
Citations number
29
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurology
Journal title
JOURNAL OF THE INTERNATIONAL NEUROPSYCHOLOGICAL SOCIETY
ISSN journal
1355-6177 → ACNP
Volume
7
Issue
3
Year of publication
2001
Pages
391 - 395
Database
ISI
SICI code
1355-6177(200103)7:3<391:TIOVEO>2.0.ZU;2-0
Abstract
Various factors influence the degree of leftward error (pseudoneglect) that typifies the performance of normal individuals in line bisection tasks. Th is experiment reveals that the eye through which stimuli are viewed also ex erts a modulating influence on spatial attention, as indexed by significant alterations in the magnitude of pseudoneglect. Using a forced-choice tachi stoscopic line bisection protocol, 24 participants (12 male; 12 female) bis ected horizontally oriented lines (22.6 degrees w X 0.39 degrees h) present ed to central vision in 3 conditions: left uniocular viewing (L), right uni ocular viewing (R), and binocular viewing (B). Perceived line midpoint, a m easure of bisection accuracy, deviated significantly leftward of veridical (p < .05) in all viewing conditions, confirming a tonic asymmetry of visuos patial attention in normal young observers. In addition, a significant infl uence of viewing condition was found (p < .05) where pseudoneglect was grea test in the L condition, followed by the B and R conditions, respectively. Analysis of the slopes of the psychometric functions revealed significantly greater bisection precision in the binocular versus uniocular viewing cond itions (p < .05). The results are interpreted to suggest that phasic effect s on spatial attention can be produced by uniocular viewing via asymmetric retinotectal projections The results are consistent with activation-orienta tion theories of attentional asymmetry.