The purpose of this study is to investigate the brain activity associated with motor and non-motor symptoms of movement disorders, including Parkinson's disease (PD) and essential tremor. These movement disorders commonly have significant non-motor features, such as depression, cognitive and memory impairment, decreased attention, speech and language disturbances, and slower processing speeds. The investigators are interested in the brain activity associated with these motor and non-motor symptoms, and propose to investigate changes in brain activity while the investigators perform recordings of the surface and deep structures of the brain, in addition to the typical recordings the investigators perform, during routine deep brain stimulation (DBS) surgery.



Eligible Ages
Over 18 Years
Eligible Genders
Accepts Healthy Volunteers

Inclusion Criteria

  • Eligible for DBS surgery based on multi-disciplinary consensus review
  • Have a diagnosis of Parkinson's disease or Essential Tremor
  • A minimum of 18 years of age
  • Willingness to participate in the paradigms described in the protocol

Exclusion Criteria

  • Inability to provide full and informed consent
  • Are not surgical candidates due to co-morbid conditions or pregnancy
  • Have not undergone an adequate trial of conservative medical management
  • Have a clinical presentation for which DBS surgery is not indicated
  • Are not able to participate in study-related activities

Study Design

Study Type
Intervention Model
Parallel Assignment
Primary Purpose
Single (Participant)

Arm Groups

ArmDescriptionAssigned Intervention
Parkinson's Disease Patients receiving DBS electrodes
  • Procedure: Response Inhibition and Deep Brain Stimulation in Parkinson's disease
    After creation of the burr hole and prior to DBS electrode placement, 1-2 subdural strip electrodes will be placed anteriorly or posteriorly from the cranial opening. These electrodes are routinely placed using this technique for seizure mapping, with arrays of electrodes (up to 6) being placed around the perimeter of the opening.14 Subdural strips vary in length and contact size (e.g., the 6-contact Ad-Tech strip), and are currently placed predominantly for studies of sensorimotor function,13 including at our institution (IRB-140327003). Placement over prefrontal areas is performed at other institutions.11-13 The DBS surgery will then proceed according to routine practice, and following lead placement in the optimal desired location, the research task paradigm will begin.
No Intervention
Control subjects will be non-Parkinson's Disease patients with essential tremor

Recruiting Locations

University of Alabama at Birmingham
Birmingham, Alabama 35233
Nicole Bentley, MD

More Details

University of Alabama at Birmingham

Study Contact

Nicole Bentley, MD

Detailed Description

Movement disorders are a prominent cause of disability worldwide. In the United States, it is estimated that more than 4 million people suffer from Parkinson's disease (PD), essential tremor (ET), and dystonia, making them some of the most prevalent of neurologic disorders. Of these, PD is the most common, and is primarily characterized by tremor, rigidity, and bradykinesia. However, though primarily characterized by motor symptoms, many patients also have prominent non-motor features, including depression and cognitive impairment, with deficiencies in processing speed, memory, attention, and learning. Some of the most debilitating cognitive deficiencies include deficits in goal-directed response selection and response inhibition, language, and/or speech difficulties, all of which substantially contribute to reduced quality of life.

Unfortunately, these features of movement disorders are less well-studied and lack effective treatment options, necessitating that new treatments be investigated. Deep brain stimulation (DBS), while a highly effective treatment for the cardinal features of PD, is essentially ineffective for, and can even worsen other cognitive domains, and there are few studies currently investigating how different parameters of DBS may improve these symptoms. In addition, speech abnormalities are common with Parkinson's disease and DBS can sometimes worsen speech problems. These impairments consists primarily of hypophonia, but cognitive deficits can result in actual language disturbance. It is often difficult to know whether the speech problems are related to language processing or articulation (related to the movement disorder). In an effort to begin addressing these questions, we propose to study motor and non-motor symptoms in patients with movement disorders, and to correlate movement and cognition with underlying neural electrophysiology.


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.