Direct Current Brain Polarization in Frontotemporal Dementia

Overview

This pilot study will evaluate the effect of direct current (DC) electrical polarization of the brain on language, memory, reaction time, and mood in six patients with frontotemporal dementia (Pick's disease). There is no effective treatment available for cognitive impairment in patients with this condition. DC polarization sends a very weak current between two sponge pads placed on the head. In a previous study in healthy volunteers, DC polarization of the left prefrontal area of the brain increased verbal fluency, memory and attention, and motor reaction time in the study subjects. Patients between 35 and 75 years of age with frontotemporal dementia who have been referred to NINDS's Cognitive Neuroscience Section for an existing protocol will be offered participation in this study. Candidates will be screened with a neurological examination to confirm the diagnosis of frontotemporal dementia. Participants receive 40 minutes of DC polarization or sham polarization in each of two separate sessions. (No current is applied in the sham treatment). During the polarization, the patient rests quietly. Sponge pads that have been soaked in water are put on the left side of the head and above the right eye, and are held in place with elastic netting. Before the polarization and after about 20 minutes of polarization, patients undergo the following tests: * Language: Patients must say as many words beginning with certain letters as they can in 90 seconds. * Memory: Patients must remember a letter on a computer screen, and when the letter appears again, press the same letter on the keyboard. * Reaction time: Patients place pegs on a pegboard. * Mood: Patients place a mark on a line ranking how they feel.

Introduction: In this study, we will use anodal direct current (DC) polarization at 2 mA to treat patients with frontotemporal dementia (FTD). Currently, there is no effective treatment for these patients. Previously, in healthy volunteers, we observed that DC polarization of the left prefrontal area for 20 min safely increases verbal fluency, cognitive processing speed (working memory and attention) and motor reaction speed. Both of these functions are severely impaired in FTD. Objective: We wish to see whether anodal DC polarization of the left prefrontal cortex in FTD patients leads to improvement in verbal fluency and working memory. Design: In this pilot study, we propose to treat six FTD patients for 40 min with anodal and sham DC polarization in a single-blind, crossover design. Outcome Measures: The main outcome measures will be verbal fluency and working memory. If anodal DC polarization produces clinically relevant improvements in these patients this will provide the impetus for a larger trial.