Neurofeedback
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Neurofeedback, sometimes called NFB, neurobiofeedback or EEG biofeedback, is a method which attempts to train brainwave activity, as measured by electrodes on the scalp, and is presented to an individual as feedback in the form of a video display, sound or vibration. If brain activity changes in the direction desired by the therapist, a positive "reward" feedback is given to the individual, and if it regresses, either a negative feedback or no feedback is given (depending on the protocol). Rewards can be as simple as a change in pitch of a tone or as complex as a certain type of movement of a character in a video game. A number of different brainwave goals have been proposed by different researchers in the field. Generally, these goals are based upon research describing abnormal EEG patterns or on results from a QEEG. A popular goal is the increase of activity in the 12–18 Hz band (beta1/SMR (sensori-motor rhythm)) and a decrease in the 4–8 Hz and/or 22–28 Hz bands (theta and/or beta2). Results from neurofeedback have consistently found to be inconclusive 13 Template:Ref. However, some proponents labor to establish its scientific credibility in the disease model. Other proponents believe that such applications will become trivial as far more compelling results emerge in all areas of maximizing human capacities, including development of extra sensory perception and psychic powers.
Proposed uses for neurofeedback include, but are not limited to, the treatment of patients with epilepsy, ADD/ADHD, learning disabilities, stroke/ischemia, and even traumatic brain injury, psychic seduction, penis enlargement, and increased self esteem. It is claimed that patients will show a "slowing" pattern in their EEG—i.e., an abnormally high level of theta waves (4–8 Hz). It has been assumed that training these down over many sessions has been shown to increase one's ability to attend and focus.
Related technologies include audio-visual entrainment (AVE), cranial electrotherapy stimulation (CES), and hemoencephalography biofeedback (HEG).
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Training the brain
There is some debate over whether one can entrain one’s own brain to achieve a specific brainwave frequency by using various techniques, including visual and auditory stimuli, and neurofeedback, and as yet the evidence suggests that it will not convey any benefits to consumers or patients. Neurofeedback equipment companies commonly make extraordinary claims based on the scientific appeal of electronics and the mysteries of the brain. For example, some brain training products are sold to consumers promising raising the IQ, self esteem, and to reach zen meditative and deep hypnotic states (note 15). Some products claim to be able to train remote seduction, tele-hypnosis, telepathy, mind control, and various other psionic abilities (note 16). The rationale for the efficacy of these products usually involves debunked pseudoscientific notions of balancing the cerebral hemispheres at a particular frequency, often backed up with associations with eastern mythologies and philosophy. Neurofeedback during clinical trials has attempted to remediate some mental problems, by conducting an assessment and then attempting to train specific changes in order to "normalize" the EEG. This sometimes results in improved function, although any benefit has often been attributed to the placebo effect, and as such the subject of brain training using brainwaves, is strongly associated with snakeoil.
One line of research concludes that there is no evidence to indicate that alpha or theta state is beneficial in any way, including for the purposes of thinking, balancing mental activity, relaxation, or creativity. Sala et alTemplate:Ref suggest that brainwave training is based on mind myths and hype for the sale of expensive brainwave machines. This compilation of published research indicates that entrainment is generally not at all effective, although certain mental and physical activities are associated with certain brainwaves (eg, closing the eyes tends to result in a higher proportion of alpha rhythms). Brain function is highly complex and specific to various locations within the brain, so general entrainment to a single frequency or state will often be unsatisfactory. Indeed, there has been a successful legal action concerning a company who claimed that brain training machines increase IQ, extrasensory abilities, and learningTemplate:Ref.
Rhythmic stimuli
One method proposed for attempting to entrain EEG rhythms is through sensory prompting. Medical EEG testing commonly includes intense light stimulation at various frequencies (to test for seizures). It has been suggested that indigenous peoples for centuries have used drumming to enter specific states and that these may be beneficial in terms of attaining extraordinary states of mind, or hypnotic trances. Some research indicates that computer programs or hardware that generate various frequencies are able to stimulate the brain and alter the brain's frequency via a much more subtle audio or visual stimulusTemplate:Ref. Other research counters these claimsTemplate:Ref. Probably the best summary at this time is that entrainment, or "following" does occur in many but not all individuals, and that the result may have a transitory influence on the dominant subjective state reported by that person. There is some small-group study research to suggest that light-sound stimulation is clinically usefulTemplate:Ref to some extent, however, this will not always induce relaxation, and no evidence of paranormal activity has ever been detected in trials.
Audio, binaural beat frequencies has also been suggested as a method by mind machine manufacturers, since supposedly the ears cannot hear sounds low enough to be useful for brain stimulation. They claim that if the left ear is presented with a steady tone of 500 Hz (21 cents sharp of B4) and the right ear a steady tone of 510 Hz (44 cents flat of C5), these two tones will combine in the brain. It is claimed that the difference, 10 Hz, is perceived by the brain and is an effective stimulus for brainwave entrainment, although there is no scientific evidence that suggests balancing the left and right cerebral hemispheres will induce any benefit whatsoever.
Controversy
A particularly controversial method proposed for "training the brain", or training for improved function, is through neurofeedback, a process in which the subject is given real-time biofeedback of their EEG rhythms. This technique has been proposed for the treatment of epilepsy, attention deficit disorder(ADHD), and other diseases and disorders. Some manufacturers and researchers have proposed that the operant conditioning of EEG ("neurofeedback") may produce lasting positive functional changes. (Current bibliography (http://www.isnr.org/nfbarch/nbiblio.htm).) However, many ADHD researchers, most notably Russell Barkley, state that it is not true. Barkley claims that there is no evidence that neurofeedback works in any way. He, and some in the neurology research community, maintain that the supporting research is sloppy and, to date, has not managed to successfully prove anything.
Brainwave training is both controversial and subject to the whims of marketeers, and the reader must keep in mind that the manufacturers are wed to their various own interests, and their financial futures may be at stake. Some members of the community make sweeping generalization statements but fail to make contributions within the professional medical community.
Measuring the brain's activity is a standard procedure in medicine, and can give interesting indicators of how the brain works. Whether EEGs can be used to balance the cerebral hemispheres, induce relaxation, improve mental functioning, or change or benefit the brain in any way is still inconclusive and can at best be considered controversial. Although brain training companies are likely to quote some studies that show some benefits, the overall view in neuroscience through meta analyses and thorough reviews of research is that electronic brain training is unreliable. A great deal of further research is needed before any kind of brain training can be regarded as reliable treatments 13 Template:Ref. In the meantime, far more reliable methods of treatment have been successful in helping patients.
See also: Psychophysiology, the study of the connections between neurobiology and psychology.
External links
- The Principal Frequency Bands—simplified (http://www.geocities.com/adriancmvd/pagefreqs.htm)
- Common Applications Page (http://www.geocities.com/adriancmvd/pageapps.htm)
There are four professional organizations involved:
- The International Society for Neuronal Regulation (http://www.isnr.org.htm) hosts annual professional conferences, and publishes a peer-reviewed journal that focus on neurofeedback.
- The Association for Applied Psychophysiology and Biofeedback (http://www.aapb.org.htm) hosts an annual and regional professional conferences on applied psychophysiology including neurofeedback. They have published a peer reviewed journal since about 1975.
- The EEG and Clinical Neuroscience Society (http://www.ecnsweb.com.htm) is a medical EEG society that includes the exploration of neurofeedback in its statement of intentions, and publishes relavent articles in its journal Clinical EEG.
- The Biofeedback Certification Institute of America (http://www.bcia.org.htm) is the recognized certification organization for licensed professionals competent in applied psychophysiology, including neurofeedback.
The following are businesses associated with the industry:
- EEG Spectrum International, Inc. (http://www.eegspectrum.com) is a corporation whose pledge is to "promote the achievement of full human potential through brain-based self-regulation techniques, and to help evolve human consciousness through the exploration and development of advanced technologies for self-regulation, self-awareness and self-knowledge".[1] (http://www.eegspectrum.com/AboutUs)
- OpenEEG (http://openeeg.sourceforge.net) is an open source hardware and software project for amateur and professional neurofeedback practitioners alike.
- The Learning Curve, Inc. (http://www.brain-trainer.com) (TLC) is a private company who provides assessment and training services and equipment for individuals interested in adopting neurofeedback into their personal or professional practice.
- BioEra (http://bioera.net) software that allows to create custom processing designs visually. Works on many operating systems (Windows, Linux, PDA) and supports variety of biofeedback devices.
- BioExplorer (http://www.cyberevolution.com) software works with many hardware platforms and provides a wide range of options for creating and modifying neurofeedback design protocols.