Abstract for the talk at 18.12.2007 (14:15 h)Arbeitsgemeinschaft NEURONALE NETZE UND KOGNITIVE SYSTEME
Tobias Elze (MPI MiS, Leipzig)
Chinese Characters and the Role of Object Perception in Visual Masking
In visual masking, a target stimulus is reduced in visibility or detectability by a second stimulus (the mask) presented in close spatiotemporal contingency. For more than one century, visual masking has been used to study perceptual timing. It remains an open debate if masking is caused solely by disruptions in bottom up processing of the visual information flow or involves feedback signals from higher visual areas. After the presentation of basic properties and classical as well as more recent experiments of visual masking, I will introduce a project that had taken place in our institute: We used Chinese characters to study the role of object perception in visual masking. I will show a number of recently performed experiments together with some preliminary results which indicate that the masking effects in our paradigm involve top down signals from higher visual areas concerned with object perception. My talk is also intended to provide feedback to the voluntary subjects from our institute who participated in the experiments.