We observed gamma-band (>40 Hz) synchronization and alpha-band (8-12 Hz) desychronization in contralateral occipital and parietal areas, both showing updating in a gaze-centered reference frame but with fast and slow time courses, respectively.
Furthermore, after updating, ipsilateral areas showed less alpha desynchronization when they had been contralateral to the target before updating.
Taken together, our results suggest that power in the gamma band is instantly reorganized to encode task-relevant visuomotor space in a gaze-centered reference frame, while power in the alpha band reflects a regulatory mechanism actively facilitating the gating of the saccade target and inhibiting the original stimulus representation.
The posterior parietal cortex (the portion of parietal neocortex posterior to the primary somatosensory cortex) plays an important role in planned movements, spatial reasoning, and attention.
In another single-cell recording experiment, neurons in parietal reach region exhibited responses consistent with either of two target locations in a sequence of planned reaching movements, suggesting that different parts of a planned sequence of locations can be represented in parallel in parietal reach region.
The parietal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals.
This effect can be dissociated from the consequences of an explicit memory recall of landmark locations, a process that further engages the retrosplenial cortex.
The superior parietal lobule and inferior parietal lobule are the primary areas of body or spacial awareness.The major sensory inputs from the skin (touch, temperature, and pain receptors), relay through the thalamus to the parietal lobe.Several areas of the parietal lobe are important in language processing.Saccadic eye movements cause sudden and global shifts in the retinal image. This “spatial updating” mechanism ensures that spatial codes for perception and action are not compromised by eye movements.Rather than causing confusion, however, eye movements expand our sense of space and detail. Spatial updating occurs in the lateral intraparietal area (LIP) as well as several other cortical and subcortical regions of the monkey brain, including the frontal eye fields (FEF) (12), the parietal reach region (8, 13), extrastriate cortex (14), and the superior colliculus (15).