By Dr Jodie Abramovitch
Non-invasive stimulation of the brain by a weak electrical current can have therapeutic effects in a range of mental illnesses such as schizophrenia and depression. A newer form of this non-invasive techniques is transcranial direct current stimulation (tDCS) which has been shown to improve cognitive processes such as working memory (includes comprehension, reasoning and learning).
|A/Prof Kate Hoy|
Recently, research conducted by Associate Professor Kate Hoy and colleagues from the Monash Alfred Psychiatry Research Centre (MAPrc) has focused on a closely related form of brain stimulation called transcranial alternating current stimulation (tACS). This method of stimulation is thought to induce changes in the brain which more closely mimics natural brain activities.
In this study, healthy individuals were given tACS, tDCS or a sham brain stimulation across separate testing sessions, at least one week apart. Working memory was tested before and after treatment via a series of computerised tasks. Results revealed that working memory was improved in participants following tACS when undertaking more difficult memory tasks. This was not seen in participants treated with tDCS or the sham treatment.
Reference: Hoy KE, Bailey N, Arnold S, Windsor K, John J, Daskalakis ZJ, Fitzgerald PB. The effect of γ-tACS on working memory performance in healthy controls. Brain Cogn. 2015 Dec; 101:51-6