Alpha Wave

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Alpha waves Alpha waves are electromagnetic oscillations in the frequency range of 8±12 Hz arising from synchronous and coherent  (in phase / constructive) constructive) electrical activity of  thalamic pacemaker  cells in humans. They are also a lso called Berger  's wave in memory of the founder of EEG. 's

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, e yes, drowsiness and sleep. Historically, they were thought to represent the act ivity ivity of o f the visual cortex in an idle state. More recent papers have argued that they inhibit areas of the cortex co rtex not in use, or alternatively [1] 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. They usually can be detected with the naked eye. An alpha-like variant called mu () can be found over the motor cortex (central scalp) that is reduced with movement, or o r the intention to move. Alpha waves do not start to appear until three [2] years of age.

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1 History of alpha waves 2 Different types of alpha waves 3 Alpha wave intrusion

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Biofeedback Training 5 Alpha waves in a gelatinous conductor  6 References 7 External links 4

[edit] History of  alpha waves Alpha waves were discovered by German neurologist Hans Berger  , most famous for his invention of the EEG. Alpha waves were among the first waves documented b y Berger, along with beta waves, and he displayed an interest in ³alpha blockage´, the process by which alpha waves decrease and beta waves increase upon a subject opening their eyes. This distinction earned the alpha wave the alternate title of ³Berger¶s Wave´. Berger took a cue from Eastern European physiologist Pravdich-Neminski, who used a string galvanometer  to create a photograph of the electrical activity of a do g's brain. Using similar  techniques, Berger confirmed the existence of electrical activity in the human brain. He first did this by presenting a stimulus to hospital patients with skull damage a nd measuring the electrical activity in their brains. Later he ceased the stimulus method and began measuring the natural rhythmic electrical cycles in the brain. The first natural rhythm he documented was what would become known as the alpha wave. Despite his brilliance, Berger was very thorough and meticulous in his data-gathering, and did not feel confident enough to publish his discoveries until at least five years after he had made them. In 1931, he published his first findings on alpha waves in the journal Archiv fur Psychiatrie. He was originally met with derision for his EEG technique and his subsequent alpha and brain wave discoveries. His technique and findings did not gain wide-spread acceptance in the psychological community until 1937, when he gained the approval of the famous physiologist Lord Adrian, who took a particular interest in alpha waves. [3]

Alpha waves again gained recognition in the early 1960¶s and 1970¶s with the creation of a biofeedback  theory relating to brain waves(see below). Such biofeedback, referred to as a kind of  neurofeedback  , relating to alpha waves is the conscious elicitation of alpha brainwaves by a subject. Two different researchers in the United Stat es explored this concept through unrelated experiments. Dr. Joe Kamiya, of the University of Chicago , discovered that some individuals had the conscious ability to recognize when they were creating alpha waves, and could increase their  alpha activity. These individuals were motivated through a reward system from Kamiya. The second progenitor of biofeedback is Dr. Barry Sterman, from the University of California, Los Angeles. He was working with monitoring brain waves in cats and found that, when the cats were trained to withhold motor movement, t hey released SMR, or mu, waves, a wave similar to alpha waves. Using a reward system, he further trained these cats to enter this state easier. Later, he was approached by the United States Air Force to test the effects of a jet fuel that was known to cause seizures in humans. Sterman tested the effects of this fuel on the previously-trained cats, and discovered that they had a higher resistance to seizures than non-trained cat s. Alpha wave biofeedback has ga ined notoriety for having some successes in humans for seizure suppression and for treatment of depression. [4]

[edit] Diff  erent types of  alpha waves Some researchers posit that there are at least three different forms of alpha waves, which may all have different functions in the wake-sleep c ycle. Alpha waves are present at different stages of the wake-sleep cycle. The most widely-researched is during the relaxed mental state, where the subject is at rest with eyes closed, but is not tired or  asleep. This alpha activity is centered in the occipital lobe, and is presumed to o riginate there, [ ] although there has been recent speculation that it instead has a thalamic origin. 5 This wave begins appearing at around four months, and is initially a frequency of  4 waves per second. The [ 6] mature alpha wave, at 10 waves per second, is firmly established by age 3. The second occurrence of alpha wave activity is during REM sleep. As opposed to the awake form of alpha activity, this form is located in a frontal-central location in the brain. The purpo se of alpha activity during REM sleep has yet to be fully understood. Currently, there are arguments that alpha patterns are a normal part of REM sleep, and for the notion that it indicates a semiarousal period. It has been suggested t hat this alpha activity is inversely related to REM sleep pressure. The third occurrence of alpha wave activity is the alpha-delta or slow-wave (SWS) state. This [ ] activity spreads across the brain in an anter ior-posterior gradient. 7 It has long been believed that alpha waves indicate a wakeful period during sleep. This has been attributed to studies where subjects report non-refreshing sleep and have E EG records reporting high levels of alpha intrusion into sleep. This occurrence is known as alpha wave intrusion. [8] However, it is possible that these explanations may be misleading, as they only focus on alpha waves being generated from the occipital lobe.

[edit] Alpha wave intrusion Alpha wave intrusion occurs when alpha waves appear with non-REM sleep when delta activity [9] is expected. It is hypothesized to be associated with fibromyalgia , although the study may be inadequate due to a small sampling size. Despite this, alpha wave intrusion has not been significantly linked to any major sleep disorder, including fibromyalgia, chronic fatigue syndrome (CNF), and major depression. However, it is common in chronic fatigued patients, and may amplify the effects of other sleep disorders. [10]

eedback Training [edit] Biof  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 a lpha 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 fad of  biofeedback training programs for everyday stress relief. Most of these have little psychological basis, and are used as fads or scams. This is not to be confused with the real potential for biofeedback in therapeutic sessions. Psychologists are hoping to use this technique to help people overcomephobias, calm down hyperactive children, and help children with stuttering problems to relax enough to practice regular speech. One psychologist, Elmer Green, is attempting to train pat ients to lower their alpha waves, as he believes that, in a low-alpha, high-theta brain state, it is easier to access unconscious problems. Similar to this relaxed-state thinking, some major companies, such as Martin Marietta and Xerox, are hoping to facilitate creative thinking in their employees through biofeedback use. There are other uses of biofeedback training beyond therapy. Defense Depart ment researchers are exploring biofeedback as a way of getting captured soldiers to create alpha waves, potentially messing up enemy lie detectors. And biofeedback training has been receiving attention as a way of monitoring attention. It has been theorized that teaching machines could use biofeedback as a way of monitoring childrens' attention, with the appearance of alpha waves signaling a lapse of  [11] attention. Following this lapse-of-attention line of thought, a recent st udy 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 co mmon sense: alpha waves indicate idleness, and mistakes are often made when a person is doing something automatically, or ³on 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 act ivity and gauge the attention level o f the [12] employee.

[edit] Alpha waves in a gelatinous conductor An initial demonstration by Upton in Britain in 1969 attracted little notice. After moving to Canada to teach at McMaster University, he tried again in 1974 at an Ontario ICU. He connected EEG leads to a dome of Jell-O, picking lime because he "thought it would be more photogenic." March 17, 1993, technicians at St. Jerome hospital in Batavia test a bowl of lime Jell-O with an EEG machine and confirm the earlier testing by Canadian Doctor Adrian Upto n in 1969 that a dome of wiggly Jell-O has brain waves identical to those of adult men and wo men. In 1969, Dr. Upton connected an electroencephalograph (EEG) to a dome of lime Jell-O, only to find the readings to be almost identical to t hose of healthy human beings.

[edit] Ref  erences 1. ^ Palva, S. and Palva, J.M., New vistas for a-frequency band oscillations, Trends Neurosci. (2007), doi:10.1016/j.tins.2007.02.001 2. ^ Kolev V, Baar-Eroglu C, Aksu F, Baar E. (199 4). EEG rhythmicities evoked by visual stimuli in three-year-old children. Int J Neurosci. 75(3-4):257-70. PMID 8050866 3. ^ Karbowski K. Hans Berger (1873-194). Journal of Neurology. 2 49(8):1310-1311 4. ^ Ulrich Kraft. Train Your Brain-Mental exercises with neurofeedback may ease symptoms of  attention-deficit disorder, epilepsy and depression--and even boost cognition in healthy brains. Scientific American. 2 006 5. ^ Domino E. F., Ni L. S., et. al(2 009). Tobacco smoking produces widespread dominant brainwave alpha frequency increases. International Journal of Psychophysiology. 74(3):192-198. 6. ^ Niedermeyer E.(1997). Alpha rhythms as physiological and abnormal phenomena. International Journal of Psychophysiology. 2 6(1-3):31-49. 7. ^ Pivik R. T., Harman K. (199 5). A Reconceptualization of EEG alpha activity as an index of  arousal during sleep: all alpha activity is not equal. Journal of Sleep Research. 4(3):131-137. 8. ^ Allas Task Force (1992). ASDA report on EEG arousals: scoring rules and examples. Sleep. 15(2):173-184. 9. ^ Germanowicz D, Lumertz MS, Martinez D, Margarites AF (2 006). "Sleep disordered breathing concomitant with fibromyalgia syndrome". J Bras Pneumol  32 (4): 333±8. PMID 17268733. 10. ^ (1994). Alpha-delta sleep in patients with a chief complaint of chronic fatigue. Southern Medical Journal. 8 7(4) 11. ^ Time. Behavior: Alpha Wave of the Future. Jul, 19 71 12. ^ U.C. Davis News and Information. Brain Wave Patterns Can Predict Blunders, New Study Finds. March 2 009.

Brazier, M. A. B. (1970), T  he Electrical Activity of the Nervous System, London: Pitman

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Psychophysiology: Sleep and sleep disorders (F51 and G47, 307.4 and 327) Sleep stages

Rapid eye movement sleep · Non-rapid eye movement sleep · Slow-wave sleep

Brain waves

Alpha wave · Beta wave · Gamma wave · Delta wave · Theta rhythm · K-complex

Sleep disorde rs

Insomnia · Narcolepsy · Sleep apnea (Obesity hypoventilation Dyssomnia syndrome, Ondine's curse) · Hypersomnia · Kleine-Levin syndrome · Sleep state misperception Circadian rhythm Advanced sleep phase syndrome · Delayed sleep phase sleep disorder syndrome · Non-24-hour sleep-wake syndrome · Jet lag · Sleepwalking · Somniloquy Parasomnia Night terror  Other/ungrouped Night eating syndrome · Nocturia · Nocturnal myoclonus ·

Benign

Dream · Exploding head syndrome · False awakening · Hypnagogia · Hypnic jerk  ·

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Related topics

Lucid dream · Nightmare · Nocturnal emission · Nocturnal penile tumescence · Sleep paralysis · Somnolence Bed (Bunk bed, Four poster bed, Futon, Daybed, Hammock  , Mattress, Sleeping bag) · Bed bug · Bedding · Bedroom · Bedtime · Bedtime toy · Bedtime story · Caffeine nap · Chronotype · Dream journal · Hypnopompic state · Lullaby · · Polyphasic sleep · Methods of falling asleep · Microsleep · Nap · Nightwear  Polysomnography · Power nap · Second wind · Siesta · Sleep and creativity · Sleep and learning · Sleep debt · Sleep deprivation · Sleep diary · Sleep inertia · Sleep · Snoring · Excessive daytime medicine · Sleeping while on duty · Sleepover  sleepiness · ("Sleeping sickness", which is not a sleep disorder.)

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EEG Alpha waves biofeedback interactive game project

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