Impact of top-down influence on visual processing during free viewing
- Fixation periods between saccadic eye movements last about 200 msec
- During fixation periods incoming information is processed, next eye movement is prepared, and behavior is initiated
- Impact of top-down influence on visual processing in these short sequences during free viewing needs to be explored
Primates perform frequent sequences of saccadic eye movements (duration about 30 msec) followed by fixations (duration about 200 msec) to sample visual information from their environment. During such a sequence, incoming visual information is processed, the next eye movement is prepared, and behavior is initiated. The information flow through the neuronal system causing these events is, however, unknown. The short time duration of the sequences suggests that incoming, sensory information and the preparation of the next eye movements are largely processed in parallel and tightly coordinated.
This joint German-Japanese project aims at getting a better understanding of the complex neuronal processing during free viewing, with a special emphasis on the interaction within and across multiple visual areas. The project requires on the one hand highly demanding experiments, which combine behavioral tasks and simultaneous electrophysiological recordings of massively parallel activity of multiple single neurons of the visual pathway. On the other hand it requires the analysis of higher-order correlations for identification of neuronal interactions within these complex multi-area multi-channel data.