The Psychotropic Effects of Vagus Nerve Stimulation in Epilepsy

There is a better understanding of comorbid conditions associated with epilepsy, particularly psychiatric disorders that have led to new treatment strategies. Based on similar sites and mechanisms of action, as well as effects on mood noted in the treatment of epilepsy, several antiepileptic medications have subsequently been studied for use in the treatment of psychiatric conditions. Carbamazapine, valproic acid, and lamotrigine, among others, have been used in the treatment of bipolar disorder. These agents have also been used as adjunctive treatment for depression. Vagus nerve has been briefly explained; it contains approximately 80% afferent fibers and 20% efferent fibers. Sensory information from the head, neck, thorax, and abdomen is carried to the nucleus of the solitary tract (NTS). From the NTS, there are bilateral projections to several areas in the brain, including the cerebellum, the periaqueductal gray, the raphe nucleus, the locus coeruleus, the limbic system, and the cerebral cortex. Thus, the Vagus nerve has a potential role in regulating seizure activity, emotion, mood, and pain.