Timing and communication of parietal cortex for visuomotor control

- Posterior parietal cortex (PPC) communicates through a wide spectrum of conduction delays.
- Lesion studies suggest a causal role of PPC in the spatial aspects of eye-hand coordination.
- Inactivation studies do not support a causal role of PPC in eye-hand temporal coupling.

In both monkeys and humans, motor cognition emerges from a parietal-frontal network containing discrete dominant domains of visual, eye and hand signals, where neurons are responsible for goal and effector selection. Within these domains, the combination of different inputs shape the tuning properties of neurons, while local and long cortico-cortical connections outline the architecture of the distributed network and determine the conduction time underlying eye-hand coordination, necessary for visually guided operations in the action space. The analysis of the communication timing between parietal and frontal nodes of the network helps understanding the sensorimotor cortical delays associated to different functions, such as online control of movement and eye-hand coordination, and opens a new perspective to the study of the parieto-frontal interactions.