Directional Motion Sensitivity under Transparent Motion Conditions

• Published in: Vision research (Oxford) 1996-08, Vol.36 (15), p.2333-2336
• Main Authors: VERSTRATEN, FRANS A.J, FREDERICKSEN, R.ERIC, van WEZEL, RICHARD J.A, BOULTON, JANE C, van de GRIND, WIM A
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Depth Perception - physiology; Directional sensitivity; Fundamental and applied biological sciences. Psychology; Humans; Male; Motion; Motion Perception - physiology; Motion transparency; Pattern Recognition, Visual - physiology; Perception; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Sensory Thresholds - physiology; Space life sciences; Suppression; Time Factors; Vision
• ISSN: 0042-6989; 1878-5646
• DOI: 10.1016/0042-6989(95)00297-9

We measured directional sensitivity to a foreground pattern while an orthogonally directed background pattern was present under transparent motion conditions. For both foreground and background pattern, the speed was varied between 0.5 and 28 deg sec −1. A multi-step paradigm was employed which results in a better estimation of the suppressive or facilitatory effects than previously applied single-step methods (e.g. measuring D max or D min). Moreover, our method gives insight into the interactions for a wide range of speeds and not just the extreme motion thresholds (the D-values). We found that high background speeds have an inhibitory effect on the detection of a range of high foreground speeds and low background speeds have an inhibitory effect on a range of low foreground speeds. Intermediate background pattern speeds inhibit the detection of both low and high foreground pattern speeds and do so in a systematic manner. Copyright © 1996 Elsevier Science Ltd.