The relative contributions of global and local acceleration components on speed perception and discriminability following adaptation.
The perception of speed is dependent on the history of previously presented speeds. Adaptation to a given speed regularly results in a reduction of perceived speed and an increase in speed discriminability and in certain circumstances can result in an increase in perceived speed. In order to determine the relative contributions of the local and global speed components on perceived speed, this experiment used expanding dot flow fields with accelerating (global), decelerating (global) and mixed accelerating/decelerating (local) speed patterns. Profound decreases in perceived speed are found when viewing low test speeds after adaptation to high speeds. Small increases in the perceived speed of high test speeds occur following adaptation to low speeds. There were small but significant differences in perceived stimulus speed after adaptation due to different acceleration profiles. No evidence for global modulation of speed discriminability following adaptation was found.
National Vision Research Institute, Australian College of Optometry, Cnr Cardigan and Keppel Street, Carlton, VIC 3053, Australia; ARC Centre of Excellence for Integrative Brain Function and Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia. Electronic address: mhietanen@nvri.org.au.
Markus A
MA
Hietanen
D000054:Acceleration; D000222:Adaptation, Physiological; D000328:Adult; D000704:Analysis of Variance; D003654:Deceleration; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D012684:Sensory Thresholds / Q000502:physiology; D055815:Young Adult
Adaptation; Discriminability; Motion; Perception; Sensitivity; Speed; Velocity