Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure.
Brain research. Cognitive brain research April 1, 2001 Y Kubota, W Sato, M Toichi et al.
Frontal midline theta rhythm (Fm theta) on EEG is linked to mental concentration, meditation, and anxiety relief, with the anterior cingulate cortex as a likely generator. This study used Zen meditation to provoke Fm theta in 12 of 25 subjects (48%), simultaneously recording EEG and ECG. During Fm theta, both cardiac sympathetic and parasympathetic indices increased compared to control periods. Frontal theta activity was negatively correlated with sympathetic activation, suggesting a close relationship between cardiac autonomic function and medial frontal neural circuitry.