Mu wave
Encyclopedia
Mu waves, also known as the comb or wicket rhythm, are electromagnetic oscillations in the frequency range of 8–13 Hz and appear in bursts of at 9 – 11 Hz. Mu wave patterns arise from synchronous and coherent (in phase/constructive) electrical activity of large groups of neurons in the human brain. This wave activity appears to be associated with the motor cortex
(central scalp), and is diminished with movement or an intent to move, or when others are observed performing actions. Researchers such as V.S. Ramachandran have suggested that EEG oscillations in the mu wave range reflect mirror neuron
activity. Recently, based on the conflicting evidence presented by mu-wave suppression experiments, Patricia Churchland
has cautioned that mu-wave suppression results cannot be used as a valid index for measuring the performance of mirror neuron systems. Mu waves are commonly detected by electroencephalography
(EEG) or magnetoencephalography (MEG). The mu wave is an alpha wave
like variant.
. In the 1950s, Gian Emilio Chatrian showed that the amplitude of mu waves could be suppressed by physical movements. Later studies showed that the simple intent to move, or certain other visual or mental tasks also can suppress mu wave amplitude.
training (often called neurotherapy or neurofeedback) is a method that enables persons to alter their brain waves via feedback regarding their present state. Research has suggested that a dysfunctional mirror neuron system may explain the pathology observed in autism spectrum disorders (ASD). Mirror neuron
s and mu waves may play a critical role in the ability to understand and imitate others' behaviors. Early research results, on enhancing mu wave activity through biofeedback
a therapy for autism
, have been promising thus far.
Motor cortex
Motor cortex is a term that describes regions of the cerebral cortex involved in the planning, control, and execution of voluntary motor functions.-Anatomy of the motor cortex :The motor cortex can be divided into four main parts:...
(central scalp), and is diminished with movement or an intent to move, or when others are observed performing actions. Researchers such as V.S. Ramachandran have suggested that EEG oscillations in the mu wave range reflect mirror neuron
Mirror neuron
A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour of the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other...
activity. Recently, based on the conflicting evidence presented by mu-wave suppression experiments, Patricia Churchland
Patricia Churchland
Patricia Smith Churchland is a Canadian-American philosopher noted for her contributions to neurophilosophy and the philosophy of mind. She has been a Professor at the University of California, San Diego since 1984...
has cautioned that mu-wave suppression results cannot be used as a valid index for measuring the performance of mirror neuron systems. Mu waves are commonly detected by electroencephalography
Electroencephalography
Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...
(EEG) or magnetoencephalography (MEG). The mu wave is an alpha wave
Alpha wave
Alpha waves are neural oscillations in the frequency range of 8–12 Hz arising from synchronous and coherent electrical activity of thalamic pacemaker cells in humans...
like variant.
History
Mu waves have been studied since the 1930s, and are referred to as the wicket rhythm because the rounded EEG waves resemble croquet wicketsCroquet
Croquet is a lawn game, played both as a recreational pastime and as a competitive sport. It involves hitting plastic or wooden balls with a mallet through hoops embedded into the grass playing court.-History:...
. In the 1950s, Gian Emilio Chatrian showed that the amplitude of mu waves could be suppressed by physical movements. Later studies showed that the simple intent to move, or certain other visual or mental tasks also can suppress mu wave amplitude.
Neurofeedback
EEG neurofeedbackNeurofeedback
Neurofeedback , also called neurotherapy, neurobiofeedback or EEG biofeedback is a type of biofeedback that uses realtime displays of electroencephalography or functional magnetic resonance imaging to illustrate brain activity, often with a goal of controlling central nervous system activity...
training (often called neurotherapy or neurofeedback) is a method that enables persons to alter their brain waves via feedback regarding their present state. Research has suggested that a dysfunctional mirror neuron system may explain the pathology observed in autism spectrum disorders (ASD). Mirror neuron
Mirror neuron
A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour of the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other...
s and mu waves may play a critical role in the ability to understand and imitate others' behaviors. Early research results, on enhancing mu wave activity through biofeedback
Biofeedback
Biofeedback is the process of becoming aware of various physiological functions using instruments that provide information on the activity of those same systems, with a goal of being able to manipulate them at will...
a therapy for autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
, have been promising thus far.
Other brain waves
- Delta waveDelta waveA delta wave is a high amplitude brain wave with a frequency of oscillation between 0–4 hertz. Delta waves, like other brain waves, are recorded with an electroencephalogram and are usually associated with the deepest stages of sleep , also known as slow-wave sleep , and aid in characterizing the...
– (0.1–4 Hz) - Theta wave – (4–7 Hz)
- Alpha waveAlpha waveAlpha waves are neural oscillations in the frequency range of 8–12 Hz arising from synchronous and coherent electrical activity of thalamic pacemaker cells in humans...
– (8–12 Hz) - Beta waveBeta waveBeta wave, or beta rhythm, is the term used to designate the frequency range of human brain activity between 12 and 30 Hz . Beta waves are split into three sections: High Beta Waves ; Beta Waves ; and Low Beta Waves...
– (12–30 Hz) - Gamma waveGamma waveA gamma wave is a pattern of neural oscillation in humans with a frequency between 25 to 100 Hz, though 40 Hz is prototypical.According to a popular theory, gamma waves may be implicated in creating the unity of conscious perception...
– (25–100 Hz)