The effects of deep TMS on QEEG power, asymmetry, and coherence metrics in major depressive disorder.

OBJECTIVE

Major depressive disorder (MDD) is one of the most prevalent and debilitating health conditions worldwide; unfortunately, numerous patients are "treatment-resistant" to traditional therapies. Deep transcranial magnetic stimulation (Deep TMS) has emerged as an effective treatment for such cases; however, the precise mechanisms by which Deep TMS alters neurophysiological patterns and attenuates depressive symptoms are still ambiguous.

METHODS

In the current study, resting-state quantitative electroencephalography (QEEG) measures of power, coherence, and asymmetry were assessed pre-and-post treatment in a sample of 75 participants with MDD.

RESULTS

The 36-session protocol yielded a response rate of 82.6 percent and an overall significant reduction in depressive symptoms. Further, slow-frequency delta activity was reduced in the left prefrontal cortex while frontal beta asymmetry shifted leftward. Coherence (brain connectivity) was also improved between the left prefrontal and temporal lobes.

CONCLUSIONS

These findings provide additional support for the utility of Deep TMS in altering aberrant neurophysiological patterns pertaining to depression.

SIGNIFICANCE: Deep TMS paired with qEEG should continue to be utilized for the treatment of MDD as well as other treatment-resistant conditions.