PROJECT SUMMARY: Neuromodulation of affective valence in humans by amygdala stimulation Studies investigating global burden of disease have shown that a significant proportion of all disability- adjusted life years are lost due to uncontrolled mental health disorders. For patients with mental illness who have not benefited from conventional psychiatric interventions, neuromodulation via deep brain stimulation (DBS) is an emerging treatment option. Multiple lines of evidence show that dysfunction of the human amygdala plays a pivotal role in the pathophysiology of many psychiatric disorders The long- term goal is to determine if the human amygdala can be a suitable DBS target to treat psychiatric disorders. The main objective for this application is to take advantage of opportunity in patients who have intracranial electrodes for epilepsy to investigate how the amygdala processes affective valence and to determine if electrical stimulation targeted to the basolateral nucleus of the amygdala can be safely used to induce a change in neural network for valence perception and on judgment of affective valence. Our central hypothesis is that electrical stimulation of the basolateral nucleus of the amygdala during performance of an affective valence perception task will change the oscillatory properties of the valence network and in turn change how patients perceive affective valence in pictures without causing the undesirable side effects of stimulation. We propose that the induction of this effect on cognition will have future implications for the treatment of specific psychiatric disorders that are known to involve the amygdala. The central hypothesis will be tested by pursuing two specific aims: (1) Characterize oscillations of the valence network during judgment of valence; (2A) measure the effect of stimulation of the basolateral nucleus of the amygdala on the oscillatory properties of the valence network; and (2B) measure the effect of basolateral nucleus of the amygdala stimulation on perception of affective valence. For Aim 1, we record and analyze intracranial EEG during perception of the Judgment of Valence and Arousal Task to gain better understanding of the oscillatory markers of affective valence. For the Aim 2A, we will use inhibitory stimulation parameters and intracranial EEG to understand how stimulation of the basolateral nucleus of the amygdala affects the oscillatory properties of neural networks for representation of valence. For Aim 2B, we will determine how stimulation affects perception and judgment of valence. The research is innovative because it uses intracranial EEG to gain understanding of neural representation of valence and how stimulation effects neural networks and behavior. The proposed research is significant because it will improve our understanding of neural representation of valence and effect of stimulation parameters on neural network. The research will provide a strong foundation for future development of amygdal...