There have been several studies in regards to correlations between psychical phenomena and the presence of physiological abnormalities during psychical performance.
This includes abnormalities found in temporal lobe functions and high amounts of densities of alpha wave activity (8-13 Hz) have been documented, which are associated with a relaxed, passive state of mind.
In single-subject designed experiments, high quality performance values have been found correlated to increased power in the delta (1-3 Hz) and theta (4-7 Hz) EEG bands, suggesting a facilitatory effect of low cortical arousal.
However, in multi-subject designed experiments, high quality performance values have been found correlated to alpha and beta activity (14-30 Hz), and low quality performance values correlated to delta and theta waves. These results may suggest that certain forms of psychical phenomena utilize different types of brain waves during performance, as they do appear to utilize different regions of the brain per form of performance.
Associated studies in the field of cardiology have suggested that alpha rhythms in the brain have correlations with the cardiac cycle during a psychophysical mode termed physiological coherence. My research has shown that an intentional increase in heart rate prior to performance produces higher performance values then in subjects who remained idle prior to performance.
This infers that if alpha wave activity is psi-conducive, then experients that can achieve physiological coherence have a practical and functional activity by which they can increase the alpha wave activity in their brain prior to performance as a means to improve performance.