Another interesting source of insight into the significance of alpha brain waves comes from extensive research that has found alpha to be a dominant wave length in the EEG scans of those who are actively meditating, and experiencing calm yet lucid, and sometimes "blissful" mental states, with minimal interruptive mental activity.
All of the studies above (with the one exception of Aftanas and Golocheikine, 2001 - selected here for its EEG scans) met Dr. Tina Huang's standards for inclusion in her landmark 2008 article, "A Comprehensive Review of the Psychological Effects of Brainwave Entrainment."
Keep reading to learn more about these studies and their incredible results.
Forty consecutive patients (25 men and 15 women) were included in the study. Twenty of the patients received photic 9 Hz alpha stimulation for 25 minutes, in addition to the usual premedications. The other twenty patients (the control group) received the same treatment, but without photic stimulation. All of the patients used a five-grade scale to evaluate the discomfort/pain they felt during endoscopy, in comparison with what they had experienced in their previous examination.
Of the patients who received the alpha stimulation, 18 out of 20 reported feeling less discomfort/pain than they had experienced before, compared to just 3/20 in the control group. Overall comparison of pain scores between both groups was statistically significant.
The EEG activity of all of the participants was measured during the test, and the group that received stimulation demonstrated significantly higher levels of slow-wave alpha activity. A clear correlation was found in the review of this EEG data: more alpha brain wave activity meant less pain.
Nomura T, Higuchi K, Yu H, et al. Slow-wave photic stimulation relieves patient discomfort during esophagogastroduodenoscopy. J Gastroenterol Hepatol. 2006;21(1 Pt 1):54-58
In 2000, a study was conducted among employees at a Dutch addiction care center to investigate the possible effects of alpha brain wave stimulation on stress and anxiety.
Subjects in the experiment were given a single stimulation session using 5 minutes of 30 Hz stimulation followed by 35 minutes of 10 Hz stimulation. Before and after the session, all of the subjects completed Spielberger's State-Trait Anxiety Inventory (STAI) test, which is an evaluation tool that is very widely used to determine stress and anxiety levels.
Those who received the stimulation showed a significant, immediate decrease in state anxiety after the sessions, and this effect was consistently demonstrated across 4 tests- the alpha stimulation resulted in lower stress levels every time.
Ossebaard HC. Stress reduction by technology? An experimental study into the effects of brainmachines on burnout and state anxiety. Appl Psychophysiol Biofeedback. 2000;25(2):93-101.
The authors of this paper explain that their study was based on research correlating 10 Hz alpha wave rhythms with memory performance, and additional studies showing that alpha activity declines along with memory due to aging.
During the test, the patients were presented with three letter words, and were given brief bursts of alpha photic stimulation, at various frequencies, as the words were presented. Later, the participants recognition of the words was tested, without any stimulation involved.
The result was that the older participants who received photic stimulation around 10.2 Hz were able to perform just as well on the test as the much younger participants. And those same stimulation frequencies increased recognition of the words more than other frequencies and the control, regardless of age.
That work was actually a continuation of a study done by Dr. Williams in 2001. Positive results were found during that earlier study as well, where the conclusion was drawn that "10Hz flicker enhances memory in healthy people and may have therapeutic potential in memory disorders."
Williams, J., Ramaswamy, D. and Oulhaj, A., 2006. 10 Hz flicker improves recognition memory in older people. BMC Neurosci. 7, 21.
Williams JH. Frequency specific effects of flicker on recognition memory. Neuroscience. 2001;104(2):283-286
Alpha brain wave activity has been observed and noted by many studies as an observable indicator of the mental state that many meditation practices seek to achieve. A review paper published in 2006 (Meditation States and Traits: EEG, ERP, and Neuroimaging Studies) cites 19 studies wherein "Alpha power increases are observed when meditators are evaluated during meditating compared with control conditions." The same review goes on to describe an additional 10 studies wherein it was shown that the alpha band "is stronger at rest in meditators compared with nonmeditator controls."
The experiments cited include observations of EEG activity from practitioners of many different meditation traditions, including Transcendental Meditation, Zen, Yoga, Tibetan Buddhists practices and Qigong.
Williams P, West M. EEG responses to photic stimulation in persons experienced at meditation. Electroencephalogr Clin Neurophysiol. 1975;39(5):519-522.
Cahn BR, Polich J. Meditation states and traits: EEG, ERP, and neuroimaging studies. Psychol Bull. 2006 Mar;132(2):180-211.