A team of researchers from University of Zagreb, Croatia, have published a study on the impact of Transcendental Meditation on brainwaves. The EEG brainwave patterns were measured as an indicator of peace and rest the TM practice could bring to people with different kinds of anxiety-related disorders.
Here’s the abstract of their paper from Psychiatria Danubina.
Changes in trait brainwave power and coherence, state and trait anxiety after three-month Transcendental Meditation (TM) practice
BACKGROUND
The amount of studies showing different benefits of practicing meditation is growing. EEG brainwave patterns objectively reflect both the cognitive processes and objects of meditation. This study aimed to examine the effects of Transcendental Meditation (TM) practice on baseline EEG brainwave patterns (outside of meditation) and to examine weather TM reduces state and trait anxiety. 
SUBJECTS AND METHODS
Standard EEG recordings were conducted on volunteer participants (N=12), all students or younger employed people, before and after a three-month meditation training. Artifact-free 100-second epochs were selected and analyzed by Fast Fourier Transformation (FFT) analysis. Endlers Multidimensional Anxiety Scales (EMAS) were used to assess anxiety levels. Power (μV(2)) and coherence levels were compared in the alpha, beta, theta and delta frequency band.
RESULTS
Changes in EEG patterns after they found mostly meditation practice in the theta band. An interaction effect was found on the left hemisphere (p<0.10).
Theta power decreased on the left, but not on the right hemisphere. Increased theta coherence was found overall and in the central, temporal and occipital areas (p<0.10).
They found decrease in alpha power on channels T3 (p<0.10), O1 (p<0.05) and O2 (p<0.10).
An interaction effect was found in the delta frequency band (p<0.06), too. A trend for power decreasing was found on the left, and a trend for power increasing on the right hemisphere. Also, power decreased on channel O1 (p<0.10).
In the beta frequency band, they found a decrease on channel O2 (p<0.10). Trait anxiety did not differ, but a decrease in state anxiety and cognitive worry was found (p<0.05).
CONCLUSIONS
The results confirm the effects of TM on some baseline EEG brainwave patterns and state anxiety, suggesting that the left hemisphere is more sensitive to meditation practice. They found most of the changes in the occipital and temporal areas, less in the central and frontal areas. State anxiety decreased after TM practice.
These findings suggest TM practice could be helpful in treating different disorders, especially anxiety disorders.
Academic reference:
Tomljenović H, Begić D, Maštrović Z. (2016) “Changes in trait brainwave power and coherence, state and trait anxiety after three-month Transcendental Meditation (TM) practice.” Psychiatria Danubina. Vol 28(1):63-72.
