What is transcranial direct current stimulation used for?

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that utilizes a low electrical current delivered through electrodes placed on the scalp. This method is specifically designed to modulate neuronal activity by delivering a direct current, which influences the excitability of neurons in targeted brain regions. The mechanism involves the alteration of resting membrane potentials, making neurons more or less likely to fire, depending on the polarity of the current applied.

This approach has been researched for various applications, including enhancing cognitive functions, alleviating symptoms of depression, and improving motor function in rehabilitation settings. The focus on direct current and its influence on neural activity distinguishes this technique from other forms of brain stimulation, such as those involving electromagnetic waves.

The other options do not accurately describe the primary function of tDCS, as they either misrepresent its mechanism (increasing fluid intake or connecting neural pathways in a manner not specific to tDCS) or confuse it with other stimulation methods.