A Vertical Asymmetry in Saccades
Abstract
Visual exploration of natural scenes imposes demands that differ between the upper and the lower visual hemifield. Yet little is known about how ocular motor performance is affected by the location of visual stimuli or the direction of a behavioural response. We compared saccadic latencies between upper and lower hemifield in a variety of conditions, including short-latency prosaccades, long-latency prosaccades, antisaccades, memory-guided sac- cades and saccades with increased attentional and selection demand. All saccade types, except memory guided saccades, had shorter latencies when saccades were directed to- wards the upper field as compared to downward saccades (p<0.05). This upper field reaction time advantage probably arises in ocular motor rather than visual processing. It may originate in structures involved in motor preparation rather than execution.
Date Issued
2015-11-04
Publication Type
Article
Subject(s)
Language(s)
en
Additional Credits
Journal
Journal of Eye Movement Research JEMR
Publisher
International Group for Eye Movement Research
ISSN
1995-8692
Access(Rights)
open.access