Sensory Filtering in the Human Basal Ganglia as a Mechanism of Parkinson's Disease

NCT ID: NCT05482126

Last Updated: 2026-01-16

Basic Information

• Recruitment Status: RECRUITING
• Total Enrollment: 30 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2022-06-08
• Study Completion Date: 2026-12-31

Brief Summary

The investigators are investigating the brain activity associated with sensory information in movement disorders in order to improve treatment of these symptoms beyond what is currently available.

Detailed Description

The purpose of this study is to investigate the functional role of the human basal ganglia in the sensorimotor system. In particular, the investigators are interested in the possibility that the basal ganglia participate in "filtering out" sensory stimuli that are irrelevant to the current behavioral goal. Additionally, the investigators are interested in how this type of sensorimotor processing in these brain areas is related to the severity of movement disorders such as Parkinson's disease and essential tremor.

To do this, the investigators will study both healthy individuals and Parkinson's disease patients undergoing routine deep brain stimulation (DBS) surgery. During the surgery, investigators will place the DBS electrode as routinely performed and additionally place an extra, temporary "strip" electrode along the surface of the brain. Participants will then perform a short behavioral task testing sensorimotor function while investigators record the neural signals from these electrodes. The task will involve the delivery of sensory stimuli (visual, vibrotactile, electrical, and/or proprioceptive), to which the participant will be asked to perform a certain motor response. In order to fully measure the variables of interest, investigators will also attach small stickers (electrodes) to the skin of areas involved in movements for measuring muscle activity (such as the face and limbs), and may attach small, noninvasive devices around the wrist, finger, or arm (e.g., accelerometers) that measure position. The investigators may also apply EEG electrodes to the scalp to measure global brain activity or place a microphone in front of the subject to record speech.

In addition to recording this baseline brain activity, the investigators will evaluate whether deep brain stimulation and dopaminergic medication alters the recorded activity and task performance. Typical deep brain stimulation involves administering specific parameters of high-frequency electrical pulses to achieve clinical benefit. Routine operations involve testing these parameters in the OR in awake patients. For this study, investigators will administer either this high-frequency stimulation or various other patterns of stimulation (e.g., low-frequency, burst stimulation) and measure the changes in behavior and brain activity. As a method of validation, the investigators will also deliver paired pulses of stimulation that enable analysis of stimulation-evoked activity.

Finally, the investigators will correlate recorded brain activity with measures of participants' individual disease severity.

Conditions

Parkinson Disease

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

Deep Brain Stimulation Surgery Patients

The investigators will seek to enroll people with Parkinson's disease (PD) who have been approved for deep brain stimulation surgery (DBS) as part of their routine clinical

Intraoperative Behavioral Testing

Intervention Type: DIAGNOSTIC_TEST

During DBS surgery, tasks will be administered via a tablet PC or mounted monitor, and the subject may hold a response box, joystick, or dynamometer to record responses. During task periods, sensory stimuli will be delivered to the participant, who may be asked to perform a motor behavior in response. Stimuli will consist of audiovisual cues presented on a computer screen, vibration applied to specific parts of the body via a tactor, mild electrical pulses delivered through the skin of specific parts of the body via the attached EMG electrodes, and/or a movement of the arm or joint. Motor responses will consist of simple movements such as finger-tapping or hand-opening, or use of a joystick or dynamometer to move a computer cursor on the screen. Participants may be asked to respond only to a particular sensory stimulus and ignore others, in order to modulate the relevance of each stimulus to the task.

Behavioral Testing

Intervention Type: DIAGNOSTIC_TEST

In the lab, tasks will be administered via a tablet PC or mounted monitor, and the subject may hold a response box, joystick, or dynamometer to record responses. During task periods, sensory stimuli will be delivered to the participant, who may be asked to perform a motor behavior in response. Stimuli will consist of audiovisual cues presented on a computer screen, vibration applied to specific parts of the body via a tactor, mild electrical pulses delivered through the skin of specific parts of the body via the attached EMG electrodes, and/or a movement of the arm or joint. Motor responses will consist of simple movements such as finger-tapping or hand-opening, or use of a joystick or dynamometer to move a computer cursor on the screen. Participants may be asked to respond only to a particular sensory stimulus and ignore others, in order to modulate the relevance of each stimulus to the task.

Healthy controls

The investigators will seek to enroll a cohort of age- and sex-matched healthy individuals to act as a control group. This group will NOT undergo DBS surgery

Behavioral Testing

Intervention Type: DIAGNOSTIC_TEST

In the lab, tasks will be administered via a tablet PC or mounted monitor, and the subject may hold a response box, joystick, or dynamometer to record responses. During task periods, sensory stimuli will be delivered to the participant, who may be asked to perform a motor behavior in response. Stimuli will consist of audiovisual cues presented on a computer screen, vibration applied to specific parts of the body via a tactor, mild electrical pulses delivered through the skin of specific parts of the body via the attached EMG electrodes, and/or a movement of the arm or joint. Motor responses will consist of simple movements such as finger-tapping or hand-opening, or use of a joystick or dynamometer to move a computer cursor on the screen. Participants may be asked to respond only to a particular sensory stimulus and ignore others, in order to modulate the relevance of each stimulus to the task.

Interventions

Intraoperative Behavioral Testing

During DBS surgery, tasks will be administered via a tablet PC or mounted monitor, and the subject may hold a response box, joystick, or dynamometer to record responses. During task periods, sensory stimuli will be delivered to the participant, who may be asked to perform a motor behavior in response. Stimuli will consist of audiovisual cues presented on a computer screen, vibration applied to specific parts of the body via a tactor, mild electrical pulses delivered through the skin of specific parts of the body via the attached EMG electrodes, and/or a movement of the arm or joint. Motor responses will consist of simple movements such as finger-tapping or hand-opening, or use of a joystick or dynamometer to move a computer cursor on the screen. Participants may be asked to respond only to a particular sensory stimulus and ignore others, in order to modulate the relevance of each stimulus to the task.

Intervention Type: DIAGNOSTIC_TEST

Behavioral Testing

In the lab, tasks will be administered via a tablet PC or mounted monitor, and the subject may hold a response box, joystick, or dynamometer to record responses. During task periods, sensory stimuli will be delivered to the participant, who may be asked to perform a motor behavior in response. Stimuli will consist of audiovisual cues presented on a computer screen, vibration applied to specific parts of the body via a tactor, mild electrical pulses delivered through the skin of specific parts of the body via the attached EMG electrodes, and/or a movement of the arm or joint. Motor responses will consist of simple movements such as finger-tapping or hand-opening, or use of a joystick or dynamometer to move a computer cursor on the screen. Participants may be asked to respond only to a particular sensory stimulus and ignore others, in order to modulate the relevance of each stimulus to the task.

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

1. Age >18 years

2. Clinically definite, advanced idiopathic PD based on consensus criteria.

3. Normal, or essentially normal, preoperative brain MRI.

4. Patient is available for follow-up visits over the length of the study

5. Patient has elected to undergo DBS surgery as part of routine care, and subthalamic nucleus (STN) is determined as the appropriate surgical target

1. Age >18 years.

2. No diagnosis of PD, other movement disorder, or other significant neurological disease.

Exclusion Criteria

1. Age <18 years.

2. Medical contraindications such as current uncontrolled hypertension, heart disease, coagulopathy, or other conditions that might increase the risk of surgery

3. Diagnosis or suspicion of atypical Parkinsonism (PSP, MSA, CBD) or drug-induced Parkinsonism, or significant neurological disease other than PD.

4. Diagnosis of psychogenic movement disorder based on consensus criteria

5. Prior DBS surgery or ablation

6. Clinical dementia and/or Dementia Rating Scale (DRS) score of <5th percentile adjusted for age and education level, based upon routine pre-op NP testing.

7. Unable to withhold dopaminergic medications for at least 12 hours prior to scheduled visit

1. Age <18 years.

2. Previous diagnosis of PD, other movement disorder, or other significant neurological disease.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 89 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Institute of Neurological Disorders and Stroke (NINDS)

NIH

Sponsor Role: collaborator

University of Alabama at Birmingham

OTHER

Sponsor Role: lead

Responsible Party

Zachary Irwin

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Zachary Irwin, PhD

Role: PRINCIPAL_INVESTIGATOR

The University of Alabama at Birmingham

Locations

The University of Alabama at Birmingham Hospital

Birmingham, Alabama, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Zachary Irwin, PhD

Role: CONTACT

zirwin@uabmc.edu

(205) 934-6704

Facility Contacts

Zachary Irwin, PhD

Role: primary

zirwin@uabmc.edu

(205) 934-6704

Other Identifiers

R01NS124563

Identifier Type: NIH

Identifier Source: secondary_id

View Link

IRB-300008936

Identifier Type: -

Identifier Source: org_study_id