Gamma wave

A gamma wave is a pattern of brain waves, associated with perception and consciousness. Gamma waves are produced when masses of neurons emit electrical signals at the rate of around 40 times a second (40 hertz or Hz), but can often be between 26 and upwards of 70 Hz. By one definition, gamma waves are manifest at 24 Hz and higher, though researchers have recognized that higher level cognitive activities occur when lower frequency gamma waves suddenly double into the 40 Hz range. Research has shown gamma waves are continuously present during low voltage fast neocortical activity (LVFA), which occurs during the process of awakening and during active rapid eye movement (REM) sleep. Some researchers do not distinguish gamma waves as a distinct class but include them in beta brain waves.

Linked to higher reasoning faculties

Gamma waves are involved in higher mental activity. Transient periods of synchronized firing over the gamma waveband, of entire banks of neurons from different parts of the brain, have been proposed as a mechanism for bringing a distributed matrix of cognitive processes together to generate a coherent, concerted cognitive act, such as perception. For example, it has been suggested that gamma waves are associated with solving the binding problem. Recent studies have shown that recognition of new insights occur when patterns jump from 20 to 40 Hz.Fact|date=September 2007

Consciousness

Gamma waves have been studied in how visual cues elicit a neural synchronic reaction with both conscious and subliminal stimuli. [ [http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=17285879&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum] Ward LM, Doesburg SM, Kitajo K, MacLean SE, Roggeveen AB. "Neural synchrony in stochastic resonance, attention, and consciousness." Can J Exp Psychol. 2006 Dec;60(4):319-26.] This research also sheds light on how neural synchrony may explain stochastic resonance in the nervous system. [ Lucia Melloni, Carlos Molina, Marcela Pena, David Torres, Wolf Singer and Eugenio Rodriguez. [http://www.jneurosci.org/cgi/pmidlookup?view=long&pmid=17360907 Final proof of role of neural coherence in consciousness?] The Journal of Neuroscience, March 14, 2007, 27(11):2858-2865; doi:10.1523/JNEUROSCI.4623-06.2007.]

Risk of false detection

There are studies showing that EEG-measured gamma waves could be in many cases an artifact of electromyographic activity cite journal |author=Whitham EM, Pope KJ, Fitzgibbon SP, "et al" |title=Scalp electrical recording during paralysis: quantitative evidence that EEG frequencies above 20 Hz are contaminated by EMG |journal=Clin Neurophysiol |volume=118 |issue=8 |pages=1877–88 |year=2007 |month=August |pmid=17574912 |doi=10.1016/j.clinph.2007.04.027 |url=http://linkinghub.elsevier.com/retrieve/pii/S1388-2457(07)00198-8] and miniature eye movements. cite journal |author=Yuval-Greenberg S, Tomer O, Keren AS, Nelken I, Deouell LY |title=Transient induced gamma-band response in EEG as a manifestation of miniature saccades |journal=Neuron |volume=58 |issue=3 |pages=429–41 |year=2008 |month=May |pmid=18466752 |doi=10.1016/j.neuron.2008.03.027 |url=http://linkinghub.elsevier.com/retrieve/pii/S0896-6273(08)00301-2] cite journal |author=Whitham EM, Lewis T, Pope KJ, "et al" |title=Thinking activates EMG in scalp electrical recordings |journal=Clin Neurophysiol |volume=119 |issue=5 |pages=1166–75 |year=2008 |month=May |pmid=18329954 |doi=10.1016/j.clinph.2008.01.024 |url=http://linkinghub.elsevier.com/retrieve/pii/S1388-2457(08)00045-X] Therefore, careful signal separation is necessary to discern them from real brain gamma-activity.

ee also

* Electroencephalography
* SMR
* Sensory Integration Dysfunction
* Holonomic brain theory
* Epilepsy
* Sleep
* Mu wave
* Alpha wave
* Beta wave
* Delta wave
* Theta wave

External links

* [http://www.epilepsyhealth.com/biofeedback.html EpilepsyHealth.com] - 'A Sampling from Chapter 3' "Biofeedback, Neurofeedback and Epilepsy", Sally Fletcher (2005)
* [http://www.nature.com/news/1999/990211/pf/990211-2_pf.html Nature.com] - 'Thinking in Synchrony', Henry Gee (February, 1999)

References

*
*

Further reading

*
* https://www.dalailama.com/news.112.htm


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Gamma (disambiguation) — Gamma is the third letter of the Greek alphabet. Gamma may also refer to:cience and mathematicsGeneral* Gamma wave, a type of brain wave * Latin gamma, used as an IPA symbol for voiced velar fricative, and in the alphabets of African languages *… …   Wikipedia

  • Gamma ray burst emission mechanisms — are theories that explain how the energy from a gamma ray burst progenitor (regardless of the actual nature of the progenitor) is turned into radiation. These mechanisms are a major topic of research as of 2007. Neither the light curves nor the… …   Wikipedia

  • Gamma ray burst progenitors — are the types of celestial objects that can emit gamma ray bursts (GRBs). GRBs show an extraordinary degree of diversity. They can last anywhere from a fraction of a second to many minutes. Bursts could have a single profile or oscillate wildly… …   Wikipedia

  • Wave vector — A wave vector is a vector representation of a wave. The wave vector has magnitude indicating wavenumber (reciprocal of wavelength), and the direction of the vector indicates the direction of wave propagation.The wave vector is most useful for… …   Wikipedia

  • Gamma ray burst — [ GRB 990123 taken on January 23, 1999. The burst is seen as a bright dot denoted by a square on the left, with an enlarged cutout on the right. The object above it with the finger like filaments is the originating galaxy. This galaxy seems to be …   Wikipedia

  • Gamma function — For the gamma function of ordinals, see Veblen function. The gamma function along part of the real axis In mathematics, the gamma function (represented by the capital Greek letter Γ) is an extension of the factorial function, with its… …   Wikipedia

  • Wave–particle duality — Quantum mechanics Uncertainty principle …   Wikipedia

  • Wave — A wave is a disturbance that propagates through space and time, usually with transference of energy. While a mechanical wave exists in a medium (which on deformation is capable of producing elastic restoring forces), waves of electromagnetic… …   Wikipedia

  • Wave equation — Not to be confused with Wave function. The wave equation is an important second order linear partial differential equation for the description of waves – as they occur in physics – such as sound waves, light waves and water waves. It arises in… …   Wikipedia

  • Wave plate — A half wave plate. Linearly polarized light entering a wave plate can be resolved into two waves, parallel (shown as green) and perpendicular (blue) to the optical axis of the wave plate. In the plate, the parallel wave propagates slightly slower …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.