Clinical Research Directory

Inclusion Criteria: * Patients with ADLD and ADLD plus tremor, as diagnosed by routine clinical examination by laryngologist, speech language pathologist, and neurologist. * Patients undergoing globus pallidus interna (GPi) deep brain stimulation (DBS) for ADLD with tremor * Age range of 18-80 years * Native speakers of American English will be recruited since there are known differences in voice and neural signals of native and non-native speakers * No evidence for dementia as assessed by neurologist. * No evidence for severe untreated mood disorder as assessed by neurologist, or as evident on self-report (Beck Depression Inventory-II score \> 29, Beck Anxiety Inventory Score \> 26. * At least 3 months since last botulinum toxin injection and the patients would need to be fully symptomatic with no residual effects of botulinum toxin on voice quality. Exclusion Criteria: * Individuals younger than 18 years and older than 80 years of age. * Women who plan to become pregnant during the study period or are currently breastfeeding. * Prior history of stroke, brain surgery, or other neurological disorder besides the one under study. * Prior laryngeal framework surgeries or other disorders affecting the vocal folds * Patients who are asymptomatic due to treatment with botulinum toxin into the vocal folds. * Presence of ferromagnetic implants and cardiac implants that would be contraindicated to MRI * Gagging or discomfort that would preclude the placement of the endoscope to visualize the larynx * Dementia, severe depression or severe anxiety. * Any clinical condition or medication judged by the investigators to potentially preclude the patient from safely completing awake brain surgery and research protocols.