CONVERGENCE OF AFFERENTS FROM SUPERIOR SAGITTAL SINUS AND TOOTH-PULP ON CELLS IN THE THALAMUS OF THE CAT

We have previously shown convergence of craniovascular and tooth pulp afferents in the cervical spinal cord of cats. This study looked for s imilar convergence in the thalamus. Fifty-four thalamic cells with inp ut from tooth pulp, superior sagittal sinus, or both, were identified. Twenty-nine cells with tooth pub and superior sagittal sinus input we re located in the ventrobasal complex or the intralaminar nuclei. Most of these 29 cells were also excited by cooling the contralateral toot h pulp, and 21 had receptive fields on the contralateral face or forel imb. Twenty cells excited by stimulation of superior sagittal sinus, a nd not tooth pulp, were found in several nuclei. The 5 cells excited b y stimulation of tooth pulp, but not sagittal sinus, were restricted t o the ventrobasal complex. The data confirm convergence from sagittal sinus, tooth pulp, and skin in the thalamus of anaesthetized cats.