Comparison of coherence, amplitude, and eLORETA patterns during Transcendental Meditation and TM-Sidhi practice.

This random-assignment study compared coherence, amplitude, and eLORETA patterns during practice of the Transcendental Meditation (TM) and the TM-Sidhi programs. The TM technique involves systematic transcending of contents of experience to a state of pure consciousness. The TM-Sidhi program involves sanyama-the simultaneous experience of dhārānā (fixity), dhyāna (transcending) and samādhi (pure consciousness). Thirty-two channel EEG was recorded from experienced TM subjects randomly assigned to two consecutive 10-min TM sessions or to a 10-min TM session followed by 10-min TM-Sidhi practice. Compared to TM practice, TM-Sidhi practice was characterized by higher frontal alpha1 and beta1 amplitudes, and eLORETA-identified sources of alpha1 EEG in right-hemisphere object recognition areas including the right parahippocampus gyrus, right fusiform gyrus, lingual gyrus, and inferior and medial temporal cortices. These cortical areas are involved in specific/holistic representation of words. The observed brain patterns support the descriptions of sanyama as including both specificity (sutras or verses), as suggested by higher frontal beta1 EEG amplitude and by eLORETA sources in right-hemisphere object-recognition areas, and holistic experience (pure consciousness) as suggested by higher frontal alpha1 EEG amplitude. These EEG patterns fit the complex description of sanyama.