A new understanding of how visual information is transformed into motor acts has emerged from recent studies of the organization of the visuomotor pathways in the primate brain. This work suggests that it may no longer be useful, or even correct, to categorize different brain areas as sensory or motor.

In the macaque, the posterior parietal cortex (PPC) integrates multimodal sensory information for planning and coordinating complex movements. In particular, the areas around the intraparietal sulcus (IPS) serve as an interface between the sensory and motor systems to allow for coordinated movements in space. Because recent imaging studies suggest a comparable functional and anatomical organiza...

Primates frequently reach toward visual targets. Neurons in early visual areas respond to stimuli in the contralateral visual hemifield and without regard to which limb will be used to reach toward that target. In contrast, neurons in motor areas typically respond when reaches are performed using the contralateral limb and with minimal regard to the visuospatial location of the target. The pari...

During sensorimotor skill acquisition, early learning of the required neuromuscular pattern and sensorimotor mappings is followed by an intermediate stage of gradually increasing consistency and efficiency of execution, which gives way, with persistent practice, to the later stages of automatization. It has been suggested that the intermediate stage is distinguished by refinements in the backgr...

Reaching to visual targets engages the nervous system in a series of transformations between sensory information and motor commands. That which remains to be determined is the extent to which the processes that mediate sensorimotor adaptation to novel environments engage neural circuits that represent the required movement in joint-based or muscle-based coordinate systems. We sought to establis...

Human superior colliculus (SC) responds in a retinotopically selective manner when attention is deployed on a high-contrast visual stimulus using a discrimination task. To further elucidate the role of SC in endogenous visual attention, high-resolution fMRI was used to demonstrate that SC also exhibits a retinotopically selective response for covert attention in the absence of significant visua...

We consider the analysis of brain networks based on multi-electrode neural recordings. Granger causality and its spectral decomposition are used to assess the directions of dynamic interactions. The effectiveness of the method is illustrated by applying it to simulated data. Then multichannel local field potential recordings from monkeys performing a visuomotor pattern recognition task are anal...

Rapid and accurate visuomotor coordination requires tight spatial and temporal sensorimotor synchronization. The introduction of a sensorimotor or intersensory misalignment (either spatial or temporal) impairs performance on most tasks. For more than a century, it has been known that a few minutes of exposure to a spatial misalignment can induce a recalibration of sensorimotor spatial relations...

Magnetoencephalography of a visual area along the human parieto-occipital sulcus suggested that this region represents the human homologue of the monkey visual area V6 complex (visual area V6/visuomotor area V6A) involved in the integration of visual and somatomotor information. We used functional magnetic resonance imaging at 2.0 T and 2 x 2 x 3 mm3 resolution (16 sections) to characterize vis...

Information about the world is often encoded in the brain as topographic maps. These internal representations are not always static but can have a dynamic nature, allowing for constant adjustments that depend on factors like experience or injury. Recently, it has been shown that areas involved in visuomotor transformations also show topographical organization. These findings suggest that it cou...