Cell-specific neuromodulation through optogenetics has inspired meticulous investigation of the basic mechanisms of neuromodulatory therapies. For instance, symptomatic control in PD animals can be achieved through excitation of parvalbumin-GPe neurons (A) and inhibition of Lim homeobox 6-GPe neurons (B), which can be optogenetically stimulated through ChR2 and Arch, respectively. Rather than being a non-specific stimulation modality, moving forward, new electrical stimulation approaches can aim to have specific intended differential effects at the cellular level (C).