Frontier Research Institute for Interdisciplinary Sciences
Tohoku University

We obtain much of our information about the outside world through our eyes. A lot of information comes in constantly through our eyes and it is impossible to process it all; so we need to efficiently process only the most important information. The human visual system is an excellent information processing system capable of such highly efficient, flexible and selective information processing.

What we see depends on spatial and temporal context. For example, in an illusion called simultaneous contrast, a gray spot looks darker on a white background than on a black background. Similar effects of context can be seen in many other visual features such as color, orientation, and depth. The human visual system uses context as a means to efficiently encode the visual information, which occasionally causes systematic errors ( = “illusions”). It is my belief that such “illusory” context effects in visual perception can give us important clues about the normal functioning of our unique information processing mechanisms.

I have studied such effects using psychophysical methods and discovered that the spatial context effect (i.e. simultaneous contrast) is much stronger in a very brief flash. The effect decays quickly with increasing duration of the stimulus, which shows that the visual system dynamically calculates the stimulus properties using context. At FRIS, I hope to further expand my research, combining a psychophysical approach with neuroscientific and engineering approaches.