Investigating Functional and Behavioral Effects of Motor Behavior After Reversible Perturbations of Macaque Ventral Premotor Cortex Using Focal Ultrasound Neuromodulation and Chemogenetic Technique

Both the amygdala (AMY) and orbitofrontal cortex (OFC) has been thought to underlay flexible changes in behavior, guided by changes in stimulus-reward associations. Besides a role of AMY in valence coding and the formation of stimulus-reward associations and reversal learning when contingencies change, it has also been suggested that OFC mediates similar functions. Object-discrimination reversal (ODR) tasks are typically used to study behavioral changes to changes in stimulus-reward associations, however there are substantial inconsistencies in the literature towards the effects of either AMY or OFC lesions on these type of reversal tasks. Here, we will investigate both behavioral and brain-wide functional network (functional activity and connectivity) consequences of reversibly inhibiting AMY or OFC during acquisition and reversal of stimulus-reward associations. Using fMRI-guided pharmacogenetic perturbations (Designer Receptors Exclusively Activated by Designer Drugs or DREADD), we will inhibit portions of either the AMY or OFC in rhesus monkeys and examine the causal effect of these perturbations on reversal learning. In addition, we will examine the effect of either AMY or OFC inhibitions (versus non-perturbed sessions) on 1) brain-wide fMRI activity during acquisition and reversal of stimulus-reward associations, and 2) functional connectivity using resting-state fMRI.