Computational specialization within the cortical eye movement system
Marshall TR., Ruesseler M., Hunt LT., O’Reilly JX.
AbstractAnimals actively sample their environment through actions such as whisking, sniffing, and saccadic eye movements. Computationally, sensorimotor control may be viewed as an interplay between two processes that place different demands on their neural circuits: a rapid/competitive process for promptly selecting each upcoming action, and a slow/integrative process weighing the outcomes of multiple prior actions to build a model of the environment. Using saccadic eye movements as a model system, we addressed the hypothesis that frontal and parietal cortex are computationally specialized for these two functions. Through biophysical modelling, we predicted neural signatures of the competitive and integrative processes. We localized these signals to the frontal eye fields and intra-parietal cortex, respectively, using whole-brain, high-temporal-resolution neuroimaging (MEG). This frontal/parietal specialization can be linked to the differential characteristics of cortical circuits, and thus may represent a more general organizing principle of sensorimotor function in the primate brain.