This short lab manual will serve as a guide to using the Chattanooga device for tDCS when working with human subjects.
Functioning of the 'Chattanooga ionto' Dual Channel Electrophoresis System
Background:Transcranial direct current stimulation (tDCS) is a non-invasive and painless procedure to modulate brain functionand does not elicit any substantial side effects. The current is applied with two sponge-electrodes over the scalp. The most common reported side-effects are a mild tingling or mild burning at the area under the electrodes during the stimulation.
Purpose: The Chattanooga ionto dual channel electrophoresis system – a device less than the size of one’s palm, is portable, low-cost, user-friendly and reliable and is capable of delivering a currentthat can be set in 0.1 mA (milliampere) increments between 0.5 mA and 4 mA. It can deliver currents up to dosages of 160mA-min.
Principle: The principle of tDCS is based on affecting neuronal excitability and modulating the firing rates of individual neurons by a low amplitude direct current which is delivered non-invasively, painlessly and safely through the scalp. This treatment is delivered to specific selected brain structures (Nitsche and Paulus, 2001). The effect of tDCS depends on the polarity – anodal or cathodal. Anodal tDCS of the human motor cortex enhances the cortical excitability due to neuronal depolarization.Cathodal tDCS, on the other hand, can induce prolonged reductions in excitability of the human motor cortex by hyperpolarizing the cortical neurons.
Scope:This write-up will serve as a guide to using the Chattanooga device for tDCS when working with human subjects.
Materials:The basic materials required are a constant current stimulator and surface electrodes. The individual components of the Chattanooga ionto dual electrophoresis system used here are the electrophoresis device, 9 volt battery, lead wires, electrodes (area about 25cm2) with rubber cushioning, sponges, self-adhering tape, wound-wash saline, scale and protractor. self-adhering tape