[size=12pt]NeuroFeedback[/size]
During the SOTT talk radio broadcast on Sunday 3rd November 2013 Nora Gedgaudas talked a lot about a science for training the human mind called NeuroFeedback.
In this article I shall attempt to deliver a very concise description of this science.
The medical science in depth is far beyond my comprehension, so I shall attempt to simplify the descriptions I use (sorry if they look too simple), and leave links to other material for the brave hearted. I have come to the conclusion that this is another of those where the deeper one digs, the bigger the hole.
History in Brief
This subject has its roots as far back as 1875, when a scientist, Richard Caton (1842 – 1926) reported the observation of electrical impulses from electrodes on the surface of living brains in animals. He observed and reported fluctuations in the impulses that increased during sleep, and in a dying animal, and after death became weaker and finally faded.
_http://en.wikipedia.org/wiki/Richard_Caton
Neurologist Hans Berger (1873 – 1941) expanded on Catons’ work and in 1924, using the most sensitive equipment available produced the first human EEG, which he called an Elektrenkephalogramm; ( Electroencephalogram. )
He was also credited with the discovery of the Alpha Wave Rhythm, also known as “Berger’s wave”.
Hans Berger ( 1873 - 1941)
One of the first EEGs recorded by Berger.
The top trace is from a young boy, the lower is a 10Hz Reference.
_http://en.wikipedia.org/wiki/Hans_Berger
Neurons, the Brain and Everything
Where do the impulses discovered by Caton and Berger originate?
The answer lies in the very make-up of our brain and nervous system. The Brain its self contains somewhere around 80 – 100 billion (depending on who you read) interconnected cells called neurons, which are special cells capable of sending a receiving electro chemical signals.
A simple Bipolar Neuron
The receptors or Dendrites are responsible for receiving signals, whilst the Axon is responsible for sending signals via the presynaptic terminal.
These cells can be a metre (3ft) or more in length, especially those that connect the skin tissue to the spinal cord or the brain stem.
There are different types of neuron for different purposes, basically there are three types:
Sensory: Send information from the skin, eyes, ears, nose, tongue etc. towards the central nervous system.
Motor: Send information from the central nervous system towards musles and glands.
Interneurons: Basically form the central nervous system, and communicate between the sensory and motor neurons.
More information can be found at: Neuroscience For Kids - cells of the nervous system
All neurons work basically in the same way, they receive or detect impulses at their receptors, and should the stimulus be sufficient, they “fire” an impulse via the Axon.
All neurons in the body are interconnected to form a neural network, which monitors and controls every single action in our body.
What we are doing when we perform an EEG, is to monitor the collective actions of the subjects neurons in various areas of the brain / central nervous system.
It is not possible to detect a single firing neuron, only the general activity in that area.
Electroencephalography
Berger’s EEG was a single trace monitor taken via a single pair of electrodes attached to the scalp. Modern EEG uses up to 256 or more electrode to monitor specific areas of the brain.
The array of electrodes used has been standardized to enable separate teams to produce comparable consistent results. This standard is called the 10-20 system, deriving its name from the placement of electrodes either 10 or 20 percent across the scalp.
EEG 10-20 System
The letters F T C P and O refer to the Frontal, Temporal, Central, Parietal and Occipital lobes of the brain.
The numbers are arranged with odd numbers on the left and even numbers on the right.
The voltages detectable when monitoring are in the micro Volt region, and therefore amplification gain of around 200,000 is required.
NOTE that as we have neurons all over our body, the measurements need not be restricted to the scalp, though to monitor peripheral neuron activity requires higher gain, and increases susceptibility to interference.
Sample EEG readout
The labels on the left indicate the electrode pairs used.
From around 1932, the raw EEG traces were further analyzed by either Fourier or Wavelet analysis to break down the raw signals into frequency spectrums.
The basic breakdown is as follows:
Delta: 1-4Hz
Theta: 4-7Hz
Alpha: 7-14Hz (Split as Alpha1: 7 – 10 & Alpha2: 11 – 14)
Beta: 15-30Hz (Split as Beta1: 15 – 17 & Beta2: 18 – 30)
Gamma: 31-100Hz (Split as Gamma1: 31 – 40 & Gamma2: 40 and over)
Mu: 8 – 13Hz Is related to the firing of Motor Neurons in a rest state.
These are however not set in stone, and some researchers will adjust the exact bands, or even merge them depending on their aim.
See:
_http://en.wikipedia.org/wiki/Quantitative_electroencephalography and
_http://en.wikipedia.org/wiki/Electr...able_of_EEG_rhythmic_activity_frequency_bands
This science alone was and is used in the diagnosis of many psychological disorders, determination of the state of a coma patient, and of brain death.
Practitioners require lengthy training and experience in order to be able to interpret EEG output and to recognize artificial aspects caused by interference from various sources.
DIY EEG
As an aside, I found this site whilst doing my research, but please bear in mind the cautionary note above relating to training!
_http://openeeg.sourceforge.net/doc/modeeg/modeeg.html
NeuroFeedback
Now we have the output of our brain and central nervous system in machine readable form, what can we do with it?
It can be observed for diagnosis, and several practitioners, including Kamiya (1968) reported that when a patient was able to observe the raw output of the EEG, the behavior of the output changed. It appeared that somehow the brain was observing its own behavior, and modifying it in some way.
This feedback has since been refined, and is used in the fields of clinical treatment, performance enhancement, functional validation studies and entertainment.
In clinical treatment it is used in the areas of attention deficit hyperactivity disorder (ADHD), epilepsy, addiction, aggression, anxiety, autism, depression, headaches, insomnia, stroke etc.
In performance enhancement, several researchers, including Vernon, Gruzelier, Landers and others have done research into improving both sporting and mental performance using NeuroFeedback.
In functional validation studies NeuroFeedback can be used to validate its own use. That is to say it may be used to determine the effects of using the various EEG frequencies for feedback.
In entertainment, it has been used for various applications, from playing music to driving remote control cars. Here I have to say, messing with ones brain to play games seems a little on the dangerous side, but I suppose there are more dangerous sports around.
Forms of Feedback
In Neurofeedback training there are two approaches, active and passive.
In active training, the subject is rewarded when a specific set of brain activities are seen, and not when they are absent; this appears to be anything from playing a video or not, to playing music the subject likes or does not like.
In passive training, a specific set of EEG traces are presented to the subject via visual, audio or motor senses. Here the behavior is modified by the practitioner changing the frequency and amplitude of the traces delivered to the subject. There are contradictions to this which define passive as the use of low energy feedback to the brain (e.g. LENS).
The exact performance of a NeuroFeedback session seems to vary with each article I found, the combinations of passive and active training together with the selection of feedback frequencies and amplitudes tends to present the subject to me as more of an art than an exact science. Though the medical profession will probably totally disagree with this, they have been using us a guinea pigs for years.
Links researched:
_http://en.wikipedia.org/wiki/Neurofeedback
_http://www.brainwellnessandbiofeedback.com/index-neurofeedback.html
_http://www.peakmind.co.uk/what-is-it.htm
_http://www.isnr.org/neurofeedback-info/learn-more-about-neurofeedback.cfm
_http://www.brainwavetraining.com/howitworks.htm
During the SOTT talk radio broadcast on Sunday 3rd November 2013 Nora Gedgaudas talked a lot about a science for training the human mind called NeuroFeedback.
In this article I shall attempt to deliver a very concise description of this science.
The medical science in depth is far beyond my comprehension, so I shall attempt to simplify the descriptions I use (sorry if they look too simple), and leave links to other material for the brave hearted. I have come to the conclusion that this is another of those where the deeper one digs, the bigger the hole.
History in Brief
This subject has its roots as far back as 1875, when a scientist, Richard Caton (1842 – 1926) reported the observation of electrical impulses from electrodes on the surface of living brains in animals. He observed and reported fluctuations in the impulses that increased during sleep, and in a dying animal, and after death became weaker and finally faded.
_http://en.wikipedia.org/wiki/Richard_Caton
Neurologist Hans Berger (1873 – 1941) expanded on Catons’ work and in 1924, using the most sensitive equipment available produced the first human EEG, which he called an Elektrenkephalogramm; ( Electroencephalogram. )
He was also credited with the discovery of the Alpha Wave Rhythm, also known as “Berger’s wave”.
Hans Berger ( 1873 - 1941)
One of the first EEGs recorded by Berger.
The top trace is from a young boy, the lower is a 10Hz Reference.
_http://en.wikipedia.org/wiki/Hans_Berger
Neurons, the Brain and Everything
Where do the impulses discovered by Caton and Berger originate?
The answer lies in the very make-up of our brain and nervous system. The Brain its self contains somewhere around 80 – 100 billion (depending on who you read) interconnected cells called neurons, which are special cells capable of sending a receiving electro chemical signals.
A simple Bipolar Neuron
The receptors or Dendrites are responsible for receiving signals, whilst the Axon is responsible for sending signals via the presynaptic terminal.
These cells can be a metre (3ft) or more in length, especially those that connect the skin tissue to the spinal cord or the brain stem.
There are different types of neuron for different purposes, basically there are three types:
Sensory: Send information from the skin, eyes, ears, nose, tongue etc. towards the central nervous system.
Motor: Send information from the central nervous system towards musles and glands.
Interneurons: Basically form the central nervous system, and communicate between the sensory and motor neurons.
More information can be found at: Neuroscience For Kids - cells of the nervous system
All neurons work basically in the same way, they receive or detect impulses at their receptors, and should the stimulus be sufficient, they “fire” an impulse via the Axon.
All neurons in the body are interconnected to form a neural network, which monitors and controls every single action in our body.
What we are doing when we perform an EEG, is to monitor the collective actions of the subjects neurons in various areas of the brain / central nervous system.
It is not possible to detect a single firing neuron, only the general activity in that area.
Electroencephalography
Berger’s EEG was a single trace monitor taken via a single pair of electrodes attached to the scalp. Modern EEG uses up to 256 or more electrode to monitor specific areas of the brain.
The array of electrodes used has been standardized to enable separate teams to produce comparable consistent results. This standard is called the 10-20 system, deriving its name from the placement of electrodes either 10 or 20 percent across the scalp.
EEG 10-20 System
The letters F T C P and O refer to the Frontal, Temporal, Central, Parietal and Occipital lobes of the brain.
The numbers are arranged with odd numbers on the left and even numbers on the right.
The voltages detectable when monitoring are in the micro Volt region, and therefore amplification gain of around 200,000 is required.
NOTE that as we have neurons all over our body, the measurements need not be restricted to the scalp, though to monitor peripheral neuron activity requires higher gain, and increases susceptibility to interference.
Sample EEG readout
The labels on the left indicate the electrode pairs used.
From around 1932, the raw EEG traces were further analyzed by either Fourier or Wavelet analysis to break down the raw signals into frequency spectrums.
The basic breakdown is as follows:
Delta: 1-4Hz
Theta: 4-7Hz
Alpha: 7-14Hz (Split as Alpha1: 7 – 10 & Alpha2: 11 – 14)
Beta: 15-30Hz (Split as Beta1: 15 – 17 & Beta2: 18 – 30)
Gamma: 31-100Hz (Split as Gamma1: 31 – 40 & Gamma2: 40 and over)
Mu: 8 – 13Hz Is related to the firing of Motor Neurons in a rest state.
These are however not set in stone, and some researchers will adjust the exact bands, or even merge them depending on their aim.
See:
_http://en.wikipedia.org/wiki/Quantitative_electroencephalography and
_http://en.wikipedia.org/wiki/Electr...able_of_EEG_rhythmic_activity_frequency_bands
This science alone was and is used in the diagnosis of many psychological disorders, determination of the state of a coma patient, and of brain death.
Practitioners require lengthy training and experience in order to be able to interpret EEG output and to recognize artificial aspects caused by interference from various sources.
DIY EEG
As an aside, I found this site whilst doing my research, but please bear in mind the cautionary note above relating to training!
_http://openeeg.sourceforge.net/doc/modeeg/modeeg.html
NeuroFeedback
Now we have the output of our brain and central nervous system in machine readable form, what can we do with it?
It can be observed for diagnosis, and several practitioners, including Kamiya (1968) reported that when a patient was able to observe the raw output of the EEG, the behavior of the output changed. It appeared that somehow the brain was observing its own behavior, and modifying it in some way.
This feedback has since been refined, and is used in the fields of clinical treatment, performance enhancement, functional validation studies and entertainment.
In clinical treatment it is used in the areas of attention deficit hyperactivity disorder (ADHD), epilepsy, addiction, aggression, anxiety, autism, depression, headaches, insomnia, stroke etc.
In performance enhancement, several researchers, including Vernon, Gruzelier, Landers and others have done research into improving both sporting and mental performance using NeuroFeedback.
In functional validation studies NeuroFeedback can be used to validate its own use. That is to say it may be used to determine the effects of using the various EEG frequencies for feedback.
In entertainment, it has been used for various applications, from playing music to driving remote control cars. Here I have to say, messing with ones brain to play games seems a little on the dangerous side, but I suppose there are more dangerous sports around.
Forms of Feedback
In Neurofeedback training there are two approaches, active and passive.
In active training, the subject is rewarded when a specific set of brain activities are seen, and not when they are absent; this appears to be anything from playing a video or not, to playing music the subject likes or does not like.
In passive training, a specific set of EEG traces are presented to the subject via visual, audio or motor senses. Here the behavior is modified by the practitioner changing the frequency and amplitude of the traces delivered to the subject. There are contradictions to this which define passive as the use of low energy feedback to the brain (e.g. LENS).
The exact performance of a NeuroFeedback session seems to vary with each article I found, the combinations of passive and active training together with the selection of feedback frequencies and amplitudes tends to present the subject to me as more of an art than an exact science. Though the medical profession will probably totally disagree with this, they have been using us a guinea pigs for years.
Links researched:
_http://en.wikipedia.org/wiki/Neurofeedback
_http://www.brainwellnessandbiofeedback.com/index-neurofeedback.html
_http://www.peakmind.co.uk/what-is-it.htm
_http://www.isnr.org/neurofeedback-info/learn-more-about-neurofeedback.cfm
_http://www.brainwavetraining.com/howitworks.htm
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