Alpha
waves are neural
oscillations in the frequency range of 7.5-12.5 Hz
arising from synchronous and coherent (in phase or constructive)
electrical activity of thalamic
pacemaker cells in humans. They are also called Berger's
wave in memory of the founder of EEG.
Alpha waves
are one type of brain
waves detected either by electroencephalography
(EEG) or magnetoencephalography
(MEG) and predominantly originate from the occipital
lobe during wakeful relaxation with closed eyes. Alpha waves are
reduced with open eyes, drowsiness and sleep. Historically, they were
thought to represent the activity of the visual cortex in an idle
state. More recent papers have argued that they inhibit areas of the
cortex not in use, or alternatively that they play an active role in
network coordination and communication. Occipital alpha waves during
periods of eyes closed are the strongest EEG brain signals.
An alpha-like variant called
mu (μ) can be
found over the motor cortex (central scalp) that is reduced with
movement, or the intention to move. Alpha waves do not start to
appear until three years of age.
Biofeedback training
Given the alpha wave's
connection with relaxed mental states, many people have latched onto
the idea of utilizing this state through a technique called
biofeedback training. This technique utilizes EEG to indicate to a
subject or trainer when the subject is in an alpha wave state, which
the subject is then instructed to remain in.
There are several different
prospects of this training that are currently being explored.
Arguably, the most popular one is the use of this training in
meditation.
Zen-trained meditation masters produce noticeably more alpha waves
during meditation. This fact has led to a popular trend of
biofeedback training programs for everyday stress relief.
Psychologists are hoping to
use this technique to help people overcome phobias,
calm down hyperactive
children, and help children with stuttering
problems to relax enough to practice regular speech.
There are other uses of
biofeedback training beyond therapy. Defense Department researchers
are exploring biofeedback as a way of getting captured soldiers to
create alpha waves, potentially foiling enemy lie detectors.
Biofeedback training has also been receiving attention as a possible
way of monitoring attention. It has been theorized that teaching
machines could use biofeedback as a way of monitoring children's
attention, with the appearance of alpha waves signaling a lapse of
attention.
Following this
lapse-of-attention line of thought, a recent study indicates that
alpha waves may be used to predict mistakes. In it, MEGs measured
increases of up to 25% in alpha brain wave activity before mistakes
occurred. This study used common sense: alpha waves indicate
idleness, and mistakes are often made when a person is doing
something automatically, or "on auto-pilot", and not paying
attention to the task they are performing. After the mistake was
noticed by the subject, there was a decrease in alpha waves as the
subject began paying more attention. This study hopes to promote the
use of wireless EEG technology on employees in high-risk fields, such
as air traffic controlling, to monitor alpha wave activity and gauge
the attention level of the employee.
Alpha waves meditation
