user based on the desired effects. For relaxation, often a reduction from beta waves to lower alpha or theta frequencies is observed. It is aimed to reach a level of “slow alpha” (8 Hz). Glickson (1986) states that an alpha frequency of 10 Hz is optimal for perceiving visual hallucinations. He assumes that it's the change in alpha activity and not the alpha activity itself that is facilitating an altered state of consciousness. After effects Even if research is not sufficient so far, Michael Hutchison and other scientists report strong tranquilizing effects that lasted up to 3 days. After several sessions it is observed that users can produce a desired brain state with the associated brainwaves easier and deliberately. Other information Therapeutic use Clinical research has been done on the use of auditory and visual stimulation to improve cognitive abilities in learning-disabled children as well as in the treatment of autism and attention deficit hyperactivity disorder (ADHD). However, lacking enough evidence to conclude that these treatments show efficacy, several studies indicate the potential to increase effects on IQ and reading levels in primary students, but also improvements in inattention and impulsiveness in children with ADHD (cite Siever). Safety Rapidly flashing lights may be dangerous for people with photosensitive epilepsy or other nervous disorders such as migraine. It is thought that one out of 10,000 adults will experience a seizure while viewing such a device; about twice as many children will have a similar ill effect. Regulation Mind machine devices are legally available throughout the United States from many sources. With some exceptions, these devices commonly do not have FDA approval for medical applications in the US. They have been found by a U.S. district court to be Class III medical devices, and consequentially require FDA pre-market approval for all medical uses. One company making medical claims for a possibly unsafe device has been shut down and seen their devices destroyed. See also Electroencephalography Event-related potential Evoked potential Hemi-Sync Human enhancement References Literature Virtual Light & Sound Machine Psychologist simulates visual brainwave entrainment using flashes on computer monitor. https://www.erowid.org/experiences/subs/exp_Devices_Mind_Machine.shtml for subjective case reports about altered states of consciousness and other effects Meditation Self Devices to alter consciousness