Adult observers' sensitivity to optic flow varies by pattern and speed

Open Access
Author:
Adamiak, William Noel
Area of Honors:
Interdisciplinary in Biology and Psychology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Rick Owen Gilmore, Thesis Supervisor
  • Dr Gong Chen, Honors Advisor
  • Richard Alan Carlson, Faculty Reader
Keywords:
  • optic flow
  • psychophysics
  • global motion
  • perception
  • behavioral neuroscience
Abstract:
In adults, radial optic flow evokes stronger brain activity than linear or rotational flow. Optic flow also evokes different activation patterns depending on motion speed (Fesi et al., 2014). This study examined whether the detection of optic flow in adult observers varies by pattern and speed in ways consistent with prior physiological evidence. Adult observers viewed two side-by-side, time varying optic flow displays that varied in pattern type and speed while judging which side contained coherent motion. As predicted, proportion correct judgments increased with motion coherence, and the response time of correct judgments declined. Observers more rapidly and accurately detected radial flow patterns, but there were no main effects of speed. Taken together the results suggest that behavioral sensitivity to detect optic flow in noise varies by pattern type and speed, in ways partially consistent with prior physiological results. This research is important as it provides baseline data for further experimentation with optic flow displays, which could be developed into novel screenings for perceptual abilities.