Trans-cranial direct current stimulation (tDCS): a promising new tool to facilitate rehabilitation of manual dexterity after stroke

Abstract

A major cause of disability after stroke is impaired contralateral manual dexterity. Recently it has been suggested that this may be at least partly due to a maladaptive increase in inhibition from the unaffected primary motor cortex (M1). Transcranial direct current stimulation (tDCS) is a non-invasive potential therapy that modulations M1 excitability via a weak electrical direct current applied to the scalp. Immediate improvement of affected hand function was obtained by anodal (excitatory) tDCS over the affected M1 or by cathodal (inhibitory) tDCS over the unaffected M1. Although the tDCS “after-effects” can last for hours to days following a 20-minute stimulation session, they are inherently transitory. There is hope that repeated tDCS sessions applied early after stroke could reduce the maladaptive neuroplasticity and aid hand dexterity rehabilitation.

Keywords

• stroke
• inter-hemispheric imbalance
• manual dexterity
• rehabilitation
• trans-cranial direct current stimulation