Laboratoire Psychologie de la Perception Institut Neurosciences Cognition Université Paris Descartes Centre National de Recherche Scientifique
Home
Research
vision Vision
action Action
speech Speech
avoc AVoC
support support staff
People
Former Staff
Teaching
Publications
Ethics
Events
Practical

Calendar
Opportunities
Internships
Contracts
Platforms
Links

Baby Lab

Intranet
Spatiotemporal characterization of a Fourier and non-Fourier motion system

Specified the spatiotemporal characteristics of reverse-phi and direct-phi motion mechanisms in experiments where 2 undergraduates had to identify the perceived direction of a given configuration. Reverse-phi perception (RPP) is progressively replaced by direct-phi perception when either the spatial or the temporal modulation of the reversed-polarity stimuli are decreased. RPP is very weak or absent for spatial and temporal frequencies <=1 c/deg and <=3.75 Hz, respectively, indicating that the sensitivity of a linear mechanism is weak or null within this frequency range. By pitting against each other reverse and direct-phi stimuli, the relative sensitivities of the putative motion mechanisms with linear (Fourier) and full-wave rectified (non-Fourier) front-end filters were assessed for a large range of spatial and temporal frequencies. The Fourier/non-Fourier distinction may be generalized in terms of a specific/unspecific dichotomy in motion processing. (PsycINFO Database Record (c) 2005 APA, all rights reserved)



URL