Vestibular and Auditory Responses in the Parietal Lobe

Abstract

A vestibular projection to the parietal lobe was demonstrated in a separate cytoarchitectural area called 2v which lies at the lateral end of the intraparietal sulcus at the junction of areas 2, 5 and 7b. Neurones in this region also respond to proprioceptive somatosensory stimuli and to optokinetic visual stimuli (Schwarz and Fredricicson 1971b, Büttner and Buettner 1978). About half of the vestibular neurones in this cortical field were activated during chair rotation to the contralateral side, whereas rotation in the opposite direction inhibited them. Optokinetic stimulation excited most of these neurones; as expected, the effective direction of rotation of the visual surround was opposite to the effective direction of head rotation. Some of these neurons were also activated by passive ümb movements or muscle tapping, and occasionally activity increased during intended head movements (Büttner and Buettner 1978).