The Effect of Transcranial Alternating Current Stimulation (tACS) on Alpha wave Absolute power of the Frontal Region in Methamphetamine Users

The aim of the study is to investigate the effect of alpha Transcranial Alternating Current Stimulation on the brain wave pattern of the frontal lobe in methamphetamine users.

This was a pre-test and post-test quasi-experimental study with control group. Twenty male methamphetamine users were selected through purposive sampling and randomly assigned into two experimental and control groups (10 in each). The QEEG was recorded in all participants to evaluate absolute power of alpha wave in the frontal lobe region. A single session transcranial alternating current stimulation (tACS), for 20 min at 10 Hz or sham, was applied to the right dorsolateral prefrontal cortex (F4). At the end, QEEG was recorded again. Collected data were analyzed by multivariate covariance method.

Findings showed that Experimental group showed greater absolute alpha power at F4, F3,F7 and Fz compared to the control group (p˂0.05).Discussion and

According to the results, 10 Hz tACS stimulation over F4 can increase alpha activity at dorsolateral, ventrolateral and central prefrontal cortex, a region of the frontal lobes that is associated with cognitive functions. Regarding to cognitive role of alpha oscillations, it can be concluded that tACS stimulation at alpha Frequency (α-tACS) can be used as a non-pharmacological method to improve cognitive function in methamphetamine users.