Technical Development of Clinical Laboratory Studies

Background:

The Human Motor Control Section does tests for people with movement disorders. In order to be sure when a test is normal or abnormal, normal values must be determined in a large group of healthy volunteers (HVs). Therefore, the researchers want to study the techniques in HVs. They will use the results as the standard of comparison in future clinical studies.

Objective:

To get enough normal results in movement tests to use in clinical studies.

Eligibility:

Healthy adults ages 18-68

Design:

Participants will be screened with medical history and physical and neurological exams.

Participants will have 1 to 3 visits. They may have:

Small sticky electrodes attached to the skin on the hands/arms and neck. These will measure muscle activity.

Tiny shocks given to a finger. Participants will be asked if they felt 1 or 2 shocks. This will be done to each hand over about 30 minutes total.

A questionnaire about anxiety.

Acoustic startle reflex test. Small electrodes will be stuck to the eye, hand, and leg. Sensors will be stuck to the palms. Small metal electrodes on the chest and inner arm will measure heart rate. Participants will wear headphones. Once everything is in place, participants will hear a low sound for about 10 minutes. They will hear a short louder sound every 45 60 seconds.

Objective

The purpose of this protocol is to get adequate normal values to compare in clinical patient studies.

Study population

There will be two techniques developed in this study: Somatosensory Temporal Discrimination Threshold (STDT) and Acoustic Startle Reflex (ASR). For both studies we will collect data systematically in an adequate sample of normal subjects.

We plan to recruit the following number of healthy volunteers (HV s) for each study.

STDT: 50 HV

ASR: 50 HV

Design

Subjects will come for up to 3 outpatient visits, during which they will participate in at least the STDT or the ASR. Before participation in any study, all participants will undergo screening for medical history and physical examination.

For the STDT, the index finger in both hands will be stimulated.

For the ASR, auditory stimulation will be administered at varying intervals. Subjects will also be asked to complete State Trait Anxiety Inventory (STAI) before participation in the study.

Outcome measures

STDT: discrimination threshold value

ASR: EMG response from seven muscles, heart rate, and galvanic skin response

Eligibility Criteria:
* INCLUSION CRITERIA:
* Between 18 and 68 years of age
* Ability to give informed consent
* Able to understand the procedures and requirements of the study

EXCLUSION CRITERIA:

* Diagnosis of a neurological disorder
* Illegal drug use within the past six months. The intent is to exclude those with drug use that may affect study results
* Self-reported consumption of \>7 alcoholic drinks a week for women and \>14 alcoholic drinks a week for men
* Unwillingness to abstain from caffeine or alcohol on the day of the study
* Abnormal findings on neurological exam of clinical significance
* History of or current brain tumor, stroke, head trauma with loss of consciousness \> few seconds, epilepsy or seizures
* Open scalp wounds or scalp infections
* For ASR, unwillingness to abstain from the use of cigarettes on the day of the study