blessings."O Nuallain,Sean in Cognitive Sciences 4(2), is the first to interrelate the work on synchronized gamma in consciousness with the well-attested work on gamma in meditation in an experimental context. It adduces experimental and simulated data to show that what both have in common is the ability to put the brain into a state in which it is maximally sensitive and consumes power at a lower (or even zero) rate, briefly. It is argued that this may correspond to a selfless state and the more typical non-zero state, in which gamma is not so prominent, corresponds to a state of empirical self. Thus, the zero power in the title refers not only to the power spectrum of the brain as measured by the Hilbert transform, but also to a psychological state of personal renunciation.Meditation and PerceptionStudies have shown that meditation has both short-term and long-term effects on various perceptual faculties.In 1984, Brown et al. conducted a study that measured the absolute threshold of perception for light stimulus duration in practitioners and non-practitioners of mindfulness meditation. The results showed that meditators have a significantly lower detection threshold for light stimuli of short duration.In 2000, Tloczynski et al. studied the perception of visual illusions (the Muller-Lyer Illusion and the Poggendorff Illusion) by zen masters, novice meditators, and non-meditators. There were no statistically significant effects found for the Muller-Lyer illusion, however, there were for the Poggendorff. The zen masters experienced a statistically significant reduction in initial illusion (measured as error in millimeters) and a lower decrement in illusion for subsequent trials.The theory of mechanism behind the changes in perception that accompany mindfulness meditation is described thus by Tloczynski:A person who meditates consequently perceives objects more as directly experienced stimuli and less as concepts... With the removal or minimization of cognitive stimuli and generally increasing awareness, meditation can therefore influence both the quality (accuracy) and quantity (detection) of perception.Brown also points to this as a possible explanation of the phenomenon: [the higher rate of detection of single light flashes] involves quieting some of the higher mental processes which normally obstruct the perception of subtle events. In other words, the practice may temporarily or permanently alter some of the top-down processing involved in filtering subtle events usually deemed noise by the perceptual filters.The Relaxation ResponseDr. Herbert Benson of the Mind-Body Medical Institute, which is affiliated with Harvard University and several Boston hospitals, reports that meditation induces a host of biochemical and physical changes in the body collectively referred to as the "relaxation response." The relaxation response includes changes in metabolism, heart rate, respiration, blood pressure and brain chemistry. Benson and his team have also done clinical studies at Buddhist monasteries in the Himalayan Mountains.Adverse effectsThe following is an official statement from the US government-run National Center for Complementary and Alternative Medicine:Meditation is considered to be safe for healthy people. There have been rare reports that meditation could cause or worsen symptoms in people who have certain psychiatric problems, but this question has not been fully researched. People with physical limitations may not be able to participate in