Effect of Electrical Stimulation (DC Polarization) to the Brain on Memory

NCT ID: NCT00471107

Last Updated: 2016-03-24

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE1/PHASE2
• Total Enrollment: 45 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2007-05-31
• Study Completion Date: 2010-04-30

Brief Summary

This study will test the effect of direct current (DC) brain polarization (the application of a very weak electrical current to the brain) on learning and memory. Earlier studies have shown that DC polarization can temporarily improve the ability of healthy people to think of certain words. This study will explore whether it can also temporarily improve learning and memory.

Healthy people 18 years of age and older may be eligible for this study. Subjects participate in two experimental sessions at the NIH Clinical Center. The first session lasts about 1 hour; the second session, on the next day, takes about 10 minutes.

At the beginning of the first session, electrodes are placed on the subject's head and arm for brain stimulation. The current may be turned on for 25 minutes, or only very briefly (sham stimulation). Subjects are not told which type of stimulation they are receiving. No stimulation is applied in the second session.

During the sessions subjects are asked to complete the following tasks that will help elucidate the effects of polarization:

• Read a list of words and remember them. Later they will try to repeat the words from memory.
• Look at a series of designs and remember them. Later they will try to draw the designs from memory.
• Push a button on a keyboard when they see a specific item (for example, when the number 7 appears).
• Generate as many words as they can think of that begin with a particular letter of the alphabet.

Subjects may be videotaped for some or all of the time during the sessions.

Detailed Description

OBJECTIVE: The principal objective is to establish whether DC polarization of left lateral prefrontal cortex can enhance verbal memory.

STUDY POPULATION: 75 healthy volunteers over the age of 18 will be enrolled.

DESIGN: The study is a double-blind parallel study with three arms: anodal polarization, cathodal polarization, and sham treatment.

OUTCOME MEASURES: The primary outcome measure is performance on the WMS-III Word Lists test. Secondary outcome measures, testing for effects of DC polarization on basic information processing and non-verbal memory, respectively, are the CalCAP and WMS-III Visual Reproduction Test. The Verbal Fluency Test will be administered prior to stimulation and 24 hours post-stimulation to screen for other residual effects of the polarization on the stimulated region.

Conditions

Healthy

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Sham TDCS

Group Type: SHAM_COMPARATOR

DC brain polarization

Intervention Type: DEVICE

0.08 mA/cm2

Surface-anodal direct current

0.08 mA/cm2

Group Type: EXPERIMENTAL

DC brain polarization

Intervention Type: DEVICE

0.08 mA/cm2

Surface-cathodal direct current

0.08 mA/cm2

Group Type: ACTIVE_COMPARATOR

DC brain polarization

Intervention Type: DEVICE

0.08 mA/cm2

Interventions

DC brain polarization

0.08 mA/cm2

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

Healthy volunteers over age 18. Pregnancy is not an exclusion.

Exclusion Criteria

Any history of a central nervous system illness or other behavioral disorder.

Broken skin in the area of the electrodes.

Uncontrolled medical problems, such as diabetes mellitus, hypertension, airway disease, heart failure, coronary artery disease, or any other condition that poses a risk for the subject during participation.

Presence of metal in the cranial cavity.

Holes in the skull made by trauma or surgery.

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

Sponsors

National Institute of Neurological Disorders and Stroke (NINDS)

NIH

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, United States

Countries

United States

References

Herwig U, Satrapi P, Schonfeldt-Lecuona C. Using the international 10-20 EEG system for positioning of transcranial magnetic stimulation. Brain Topogr. 2003 Winter;16(2):95-9. doi: 10.1023/b:brat.0000006333.93597.9d.

Reference Type: BACKGROUND

PMID: 14977202 (View on PubMed)

BINDMAN LJ, LIPPOLD OC, REDFEARN JW. Long-lasting changes in the level of the electrical activity of the cerebral cortex produced bypolarizing currents. Nature. 1962 Nov 10;196:584-5. doi: 10.1038/196584a0. No abstract available.

Reference Type: BACKGROUND

PMID: 13968314 (View on PubMed)

CREUTZFELDT OD, FROMM GH, KAPP H. Influence of transcortical d-c currents on cortical neuronal activity. Exp Neurol. 1962 Jun;5:436-52. doi: 10.1016/0014-4886(62)90056-0. No abstract available.

Reference Type: BACKGROUND

PMID: 13882165 (View on PubMed)

Other Identifiers

07-N-0147

Identifier Type: -

Identifier Source: secondary_id

070147

Identifier Type: -

Identifier Source: org_study_id