Understanding the basic mechanisms underlying the perception and control of pain signals originating from the oro-facial region is the aim of Dr. Mokha's research program. While it is known that the processing of pain signals from the oro-facial region takes place initially in the dorsal horn of the medulla (trigeminal nucleus caudalis) and is relayed to higher centers of the brain involved in the perception of pain, Dr. Mokha will delineate the importance of opiates and opiod peptides in modulating pain transmission. These opiates and opioid peptides are morphine like compounds localized in these brain regions. Moreover, he will determine the contribution of pathways descending from the hypothalamus to the dorsal horn in modulating pain signals originating from the oro-facial region. The new knowledge gained from these type of work will eventually lead to the development of new and better strategies for controlling clinical pain states such as trigeminal neuralgia (tic douloureux), migraine and other debilitating pains associated with spinal cord or peripheral nerve injuries and other disease processes. Understanding the neural mechanisms and neurochemicals that underlie the modulation of pain signals in the dorsal horn should lead to the development of new non-addictive analgesic drugs for the treatment of pain.