J Neurophysiol (May 1, 2003). 10.1152/jn.00599.2002
Submitted on Submitted 24 July 2002; accepted in final form 24 January 2003

Cortical Projection of Peripheral Vestibular Signaling

 ¹Positron Emission Tomographic Centre, University of Debrecen, Medical and Health Science Center, 4026 Debrecen;  ²Department of Othorhinolaryngology, Markusovszky Hospital of the County Seat Town of Szombathely in Vas County, Markusovszky út 3., Szombathely, 9700;  ³Department of Neurosurgery, University of Debrecen, Medical and Health Science Center, Nagyerdei krt. 98., Debrecen, 4026;  ⁴HUNIKO Medical Services and Commercial Ltd., Petfi út 13., Miskolc, 3530; Kerepestarcsa;  ⁵Department of Otorhinolaryngology University of Debrecen, Medical and Health Science Center, Nagyerdei krt. 98., Debrecen, 4026; and  ⁶PET Study Group of the Hungarian Academy of Science, Bem tér 18/C, Debrecen, 4012, Hungary

Emri, Miklós, Mihály Kisely, Zsolt Lengyel, László Balkay, Teréz Márián, László Mikó, Ervin Berényi, István Sziklai, Lajos Trón, and Ágnes Tóth. Cortical Projection of Peripheral Vestibular Signaling. J. Neurophysiol. 89: 2639-2646, 2003. The cerebral projection of vestibular signaling was studied by using PET with a special differential experimental protocol. Caloric vestibular stimulation (CVS)-induced regional cerebral blood flow (rCBF) changes were investigated in two populations. Butanol perfusion scans were carried out on six healthy volunteers and on six patients following the removal of tumors from the right cerebello pontine angle. The complete loss of the vestibular function postoperatively allowed a comparison of the rCBF changes in the populations with or without this input and offered a promising functional approach whereby to delineate the cortical region most responsive to pure vestibular input. The activations by left-sided and right-sided CVS were determined for both the healthy volunteers and the patient population. Statistical analysis of the data obtained following left-sided CVS did not reveal any cerebral region for which there was a significant difference in CVS-induced response by these two populations. In the case of right-sided CVS, however, the statistical comparison of the CVS-related responses demonstrated a single contralateral area characterized by a significantly different degree of response. This cortical area corresponds to part of the cortical region described recently which can be activated by both CVS and neck vibration. It appears to be anatomically identical to the aggregate of the somatosensory area SII and the retroinsular cortex described in primates, a region identified by other investigators as an analog of the parietoinsular vestibular cortex.