Purchase this article with an account.
Yasuhiko Saito, Kenzo Sakurai; The inverted vection caused by expanding/contracting random-dot patterns. Journal of Vision 2013;13(9):956. doi: 10.1167/13.9.956.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The "inverted vection" is self-motion perception in the same direction as a foreground motion induced by the slowly moving foreground with an orthogonally moving background (Nakamura & Shimojo, 2000). Using expanding/contracting visual stimulus pattern that will not induce optokinetic nystagmus (OKN), we extended their study to (1) investigate whether the inverted vection in depth occurs or not, and to (2) reexamine their claim that the mis-registration of eye movement by suppression of OKN causes inverted vection (Nakamura & Shimojo, 2003). Observers wore a shutter goggle for stereoscopic vision, and viewed stimuli on a screen in 120 cm viewing distance. A fixation cross was always presented in the center of screen surface. The background pattern was perceived to be 15cm farther than the screen with rightward translating random-dots at a constant speed of 25 deg/s. The foreground pattern was perceived to be 15cm nearer than the screen with expanding/contracting random-dots at 5 constant accelerations (0.056, 0.223, 0.893, 3.571, 14.286 deg/sec[sup]2[/sup]). Both foreground and background patterns were presented in the experimental condition. Only the foreground pattern was presented in the control condition. Observers performed key-press to report their perceived forward/backward self-motion, and the reported direction and duration of self-motion were recorded. In experimental condition, observers reported inverted vection when the foreground random-dots expanded/contracted slowly, and they reported ordinary vection when the random-dots expanded/contracted fast. In control condition, the duration of the self-motion sensation varied linearly with the speed of stimulus motion. The faster motion induced the stronger self-motion sensation in the direction opposite to the pattern motion. These results suggest that (1) the inverted vection in depth occurs, and (2) there must be some factor for the inverted vection other than the mis-registration of eye movement by suppression of OKN.
Meeting abstract presented at VSS 2013
This PDF is available to Subscribers Only