IPM

“ Schools ”

“ Centers and Units ”

“ Research Groups ”

“ Useful Links ”

“ E-Services ”

“School of Cognitive”

Paper IPM / Cognitive / 8973

School of Cognitive Sciences

Title:

The effect of flashing stimuli on the motion perception of remote moving objects

Author(s):

1 .	M. Adibi
2 .	A. Ezzati

Status:

In Proceedings

Proceeding:

The European Conference on Visual Perception (ECVP) St. Petersburg

Year:

2006

Supported by:

IPM

Abstract:

We used a spatiotemporal weighted averaging model of motion perception in which the perception attributed to the position of a moving object at time t is a function of its positions in a time interval [t - a, t +b ]. To determine the model parameters, we designed a motion reversal paradigm in which two bars at the opposite sides of the screen moved towards each other, and when they met the direction of their motion reversed. The subjects perceived that the motion reversal occured before the stimuli reached each other. To determine the effect of flashing stimuli, two flashes appeared at the time of motion reversal. The dependence of the perceived misalignment between flashes and the moving stimuli on both pre- and post-flash speed of the moving stimuli indicates that motion perception system is neither predictive as proposed by Nijhawan (1994 Nature 370 256-257), nor postdictive as proposed by Eagleman and Sejnowski (2000 Science 287 2036 - 2038), but it uses a time window of 160 ms to calculate the position of moving objects at a time within this interval. Comparison of the results indicates that the flash has no significant effect on both the limits of the time window of integration and the weights [Supported by the School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran, the Laboratories for Brain and Cognitive Sciences, Shaheed Beheshti University of Medical Sciences, Tehran, and the Iran University of Science and Technology, Tehran.]

Download TeX format