Characterization of Gastric Evoked Potentials
Study Details
Study Description
Brief Summary
This is an exploratory study that will determine and standardize how best to record gastric evoked potentials (GEPs) elicited by a non-invasive method of brain stimulation (Transcranial Magnetic Stimulation, TMS), by optimizing the TMS parameters and cortical sites necessary to evoke GEPs.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
The overall goal of this exploratory study is to determine the optimal conditions to elicit gastric evoked potentials (GEPs) with Transcranial Magnetic Stimulation (TMS).
Aim 1: Determine the optimal stimulation parameters and the optimal location for eliciting GEPs in cortical motor areas.
Aim 2: Determine whether various modes of repetitive TMS (rTMS) neuromodulation targeted to GEP hotspots shape gastric motor responses to a water load.
The investigators will record some clinical, demographic, and autonomic data (i.e. EKG) in our enrolled subjects. Secondary analyses will use these variables as covariates to investigate any systematic impact on the measures from Aims 1 and 2.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: All participants All participants |
Procedure: Transcranial Magnetic Stimulation, TMS
The best location for evoking an electromyographic (EMG) response of the first dorsal interosseus (FDI) muscle in the dominant hand and the minimum stimulation intensity required to evoke a certain EMG response amplitude (Motor Threshold, MT) are used as reference to determine the best location and stimulation parameters to evoke GEPs.
After identification of the GEP hot-spot, a water load test is administered to determine whether satiety shapes GEP responses.
In subsequent study visits, the water load test is preceded by application of neuromodulatory repetitive TMS (rTMS), targeted to the GEP hotspot.
|
Outcome Measures
Primary Outcome Measures
- Change in GEP hotspot location [Multiple study sessions spanning up to 12 months]
Stimulation location evoking the largest GEP response, relative to FDI hotspot location
- Change in optimal stimulation parameters at GEP hotspot [Multiple study sessions spanning up to 12 months]
Stimulation pattern (single pulses or brief bursts) and strength relative to MT for FDI
Secondary Outcome Measures
- Effect of satiety [Multiple study sessions spanning up to 12 months]
Change in GEP amplitude after water load test
- Effect of neuromodulation [Multiple study sessions spanning up to 12 months]
Change in GEP amplitude when water load test is preceded by rTMS
Eligibility Criteria
Criteria
Inclusion Criteria:
Exclusion Criteria:
-
psychosis or altered cognitive status
-
history of head injury, metal in the skull, stroke, or a history of seizures, loss of consciousness or syncope
-
implantable devices, such as a pacemaker or nerve stimulator
-
current use of antiepileptic medications or current use of the following medications or substances which are known to lower the seizure threshold: Clozapine (Clozaril), Chlorpromazine (Thorazine), amphetamines or methamphetamine, Ecstasy, Ketamine, Angel Dust/PCP, cocaine, or 3 or more alcoholic drinks per day
-
pregnancy
-
BMI > 30
-
history of bariatric surgery such as sleeve gastrectomy or Roux-en-Y gastric bypass
-
diabetes
-
suffering from a neurodegenerative disorder.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University of Pittsburgh Medical Center | Pittsburgh | Pennsylvania | United States | 15232 |
Sponsors and Collaborators
- University of Pittsburgh
- National Institute of Neurological Disorders and Stroke (NINDS)
Investigators
- Principal Investigator: David J Levinthal, MD PhD, University of Pittsburgh
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- STUDY23030127
- R21NS123502