Neurofeedback

Software real time data of neurofeedback training.

Neurofeedback (NFB), also called neurotherapy or neurobiofeedback, is a type of biofeedback that uses real-time displays of brain activity—most commonly electroencephalography (EEG), to teach self-regulation of brain function. Typically, sensors are placed on the scalp to measure activity, with measurements displayed using video displays or sound.

Definition

Neurofeedback is a type of biofeedback that measures brain waves to produce a signal that can be used as feedback to teach self-regulation of brain function.[1] Neurofeedback is commonly provided using video or sound, with positive feedback for desired brain activity and negative feedback for brain activity that is undesirable. Related technologies include hemoencephalography biofeedback (HEG) and functional magnetic resonance imaging (fMRI) biofeedback.

Uses

ADHD

Clinical guidelines on neurofeedback as a treatment for ADHD are mixed. Neurofeedback is graded by the American Academy of Pediatrics with their highest rating: Level 1 evidenced based treatment for ADHD. Neurofeedback has held this status since 2012.[2] The NICE guideline for ADHD leaves the efficacy of biofeedback an open question (p. 412). In page 202 states "Biofeedback has been employed as a non-invasive treatment for children with ADHD since the 1970s but is probably not used as a significant intervention in UK clinical practice". SIGN guideline no 112 in page 24 mentions "Neurofeedback is presently considered to be an experimental intervention in children and young people with ADHD/HKD. There are no standardised interventions".[3] Institute for Clinical Systems Improvement guideline on Diagnosis and Management of Attention Deficit Hyperactivity Disorder in Primary Care for School-Age Children and Adolescents in page 41 mentions neurofeedback lacks enough research evidence for efficacy in ADHD.[4]

Overall research into neurofeedback is considered to have been limited and of low quality,[4][5][6] although others have disagreed.[7]

It has been argued there is some indication on the effectiveness of biofeedback for ADHD but that it is not conclusive: several studies have yielded positive results, however the best designed ones have either shown absent or reduced effects.[4][5][5][6][6][8] Other experts have proposed that standard neurofeedback protocols for ADHD, such as theta/beta, SMR and slow cortical potentials neurofeedback are well investigated and have demonstrated specificity.[9] No serious adverse side effects from neurofeedback have been reported.[5]

QEEG has been used to develop EEG models of ADHD. According to this model, persons with ADHD often have too many slow theta brain waves (associated with relaxation) and not enough fast beta wave activity (associated with mental focus).[10] Neurofeedback therapies for ADHD generally attempt to increase the production of betawaves and decrease the number of slower brain waves. This can be accomplished by allowing the patient to view their levels of brain waves on a screen and attempt to alter them, or by integrating brain waves into a video game.[11]

Other medical uses

Research shows neurofeedback may be a potentially useful intervention for a range of brain-related conditions. It has been used for pain,[12] addiction,[13][14][15][16] aggression,[17] anxiety,[11] autism,[18] depression,[19] Schizophrenia,[20][21]epilepsy,[22] headaches,[23] insomnia,[24] Tourette syndrome,[25] and brain damage from stroke,[26] trauma,[27] and other causes.

Non-medical

The applications of neurofeedback to enhance performance extend to the arts in fields such as music, dance, and acting. A study with conservatoire musicians found that alpha-theta training benefitted the three music domains of musicality, communication, and technique.[28] Historically, alpha-theta training, a form of neurofeedback, was created to assist creativity by inducing hypnagogia, a “borderline waking state associated with creative insights”, through facilitation of neural connectivity.[29] Alpha-theta training has also been shown to improve novice singing in children. Alpha-theta neurofeedback, in conjunction with heart rate variability training, a form of biofeedback, has also produced benefits in dance by enhancing performance in competitive ballroom dancing and increasing cognitive creativity in contemporary dancers. Additionally, neurofeedback has also been shown to instil a superior flow state in actors, possibly due to greater immersion while performing.[29]

However, randomized control trials have found that neurofeedback training (using either sensorimotor rhythm or theta/beta ratio training) did not enhance performance on attention-related tasks or creative tasks.[30] It has been suggested that claims made by proponents of alpha wave neurofeedback training techniques have yet to be validated by randomized, double-blind, controlled studies,[31] a view which even some supporters of alpha neurofeedback training have also expressed.[32]

History and application

In 1924, the German psychiatrist Hans Berger connected a couple of electrodes (small round discs of metal) to a patient's scalp and detected a small current by using a ballistic galvanometer. During the years 1929-1938 he published 14 reports about his studies of EEGs, and much of our modern knowledge of the subject, especially in the middle frequencies, is due to his research.[33] Berger analyzed EEGs qualitatively, but in 1932 G. Dietsch applied Fourier analysis to seven records of EEG and became the first researcher of what later is called QEEG (quantitative EEG).[33]

Later, Joe Kamiya popularized neurofeedback in the 1960s when an article[34] about the alpha brain wave experiments he had been conducting was published in Psychology Today in 1968. Kamiya’s experiment had two parts. In the first part, a subject was asked to keep his eyes closed and when a tone sounded to say whether he thought he was in alpha. He was then told whether he was correct or wrong. Initially the subject would get about fifty percent correct, but some subjects would eventually develop the ability to better distinguish between states.[35] In the second part of the study, subjects were asked to go into alpha when a bell rang once and not go into the state when the bell rang twice. Once again some subjects were able to enter the state on command. Alpha states were connected with relaxation, and alpha training had the possibility to alleviate stress and stress-related conditions.

Despite these claims, the universal correlation of high alpha density to a subjective experience of calm cannot be assumed. Alpha states do not seem to have the universal stress-alleviating power indicated by early observations.[36] At one point, Martin Orne and others challenged the claim that alpha biofeedback actually involved the training of an individual to voluntarily regulate brainwave activity.[37] James Hardt and Joe Kamiya, then at UC San Francisco's Langley Porter Neuropsychiatric Institute published a paper that supported biofeedback.[38]

In the late sixties and early seventies, Barbara Brown, one of the most effective popularizers of Biofeedback, wrote several books on biofeedback, making the public much more aware of the technology. The books included New Mind New Body, with a foreword from Hugh Downs, and Stress and the Art of Biofeedback. Brown took a creative approach to neurofeedback, linking brainwave self-regulation to a switching relay which turned on an electric train.[39]

The work of Barry Sterman, Joel F. Lubar and others has been relevant on the study of beta training, involving the role of sensorimotor rhythmic EEG activity.[40] This training has been used in the treatment of epilepsy,[41][42] attention deficit disorder and hyperactive disorder,.[43] The sensorimotor rhythm (SMR) is rhythmic activity between 12 and 16 hertz that can be recorded from an area near the sensorimotor cortex. SMR is found in waking states and is very similar if not identical to the sleep spindles that are recorded in the second stage of sleep.

For example Sterman has shown that both monkeys and cats who had undergone SMR training had elevated thresholds for the convulsant chemical monomethylhydrazine. These studies indicate that SMR may be associated with an inhibitory process in the motor system.[42]

Within the last 5–10 years, neurofeedback has taken a new approach in taking a look at deep states.[44] Alpha-theta training has been tried with patients with alcoholism,[45] other addictions as well as anxiety.[45] This low frequency training differs greatly from the high frequency beta and SMR training that has been practiced for over thirty years and is reminiscent of the original alpha training of Elmer Green and Joe Kamiya.[45] Beta and SMR training can be considered a more directly physiological approach, strengthening sensorimotor inhibition in the cortex and inhibiting alpha patterns, which slow metabolism. Alpha-theta training, however, derives from the psychotherapeutic model and involves accessing of painful or repressed memories through the alpha-theta state.[46] The alpha-theta state is a term that comes from the representation on the EEG.

A recent development in the field is a conceptual approach called the Coordinated Allocation of Resource Model (CAR) of brain functioning which states that specific cognitive abilities are a function of specific electrophysiological variables which can overlap across different cognitive tasks.[47] The activation database guided EEG biofeedback approach initially involves evaluating the subject on a number of academically relevant cognitive tasks and compares the subject's values on the QEEG measures to a normative database, in particular on the variables that are related to success at that task.

Organizations

The Association for Applied Psychophysiology and Biofeedback (AAPB) is a non-profit scientific and professional society for biofeedback and neurofeedback. The International Society for Neurofeedback and Research (ISNR) is a non-profit scientific and professional society for neurofeedback.[48] The Biofeedback Foundation of Europe (BFE) sponsors international education, training, and research activities in biofeedback and neurofeedback.

Certification

The Biofeedback Certification International Alliance (formerly the Biofeedback Certification Institute of America) is a non-profit organization that is a member of the Institute for Credentialing Excellence (ICE). BCIA certifies individuals who meet education and training standards in biofeedback and neurofeedback and progressively recertifies those who satisfy continuing education requirements. BCIA offers biofeedback certification, neurofeedback (also called EEG biofeedback) certification, and pelvic muscle dysfunction biofeedback certification. BCIA certification has been endorsed by the Mayo Clinic,[49] the Association for Applied Psychophysiology and Biofeedback (AAPB), the International Society for Neurofeedback and Research (ISNR), and the Washington State Legislature.[50]

The BCIA didactic education requirement includes a 36-hour course from a regionally accredited academic institution or a BCIA-approved training program that covers the complete Neurofeedback Blueprint of Knowledge and study of human anatomy and physiology. The Neurofeedback Blueprint of Knowledge areas include: I. Orientation to Neurofeedback, II. Basic Neurophysiology and Neuroanatomy, III. Instrumentation and Electronics, IV. Research, V. Psychopharmalogical Considerations, VI. Treatment Planning, and VII. Professional Conduct.[51]

Applicants may demonstrate their knowledge of human anatomy and physiology by completing a course in biological psychology, human anatomy, human biology, human physiology, or neuroscience provided by a regionally accredited academic institution or a BCIA-approved training program or by successfully completing an Anatomy and Physiology exam covering the organization of the human body and its systems.

Applicants must also document practical skills training that includes 25 contact hours supervised by a BCIA-approved mentor designed to them teach how to apply clinical biofeedback skills through self-regulation training, 100 patient/client sessions, and case conference presentations. Distance learning allows applicants to complete didactic course work over the internet. Distance mentoring trains candidates from their residence or office.[52] They must recertify every 4 years, complete 55 hours of continuing education (30 hours for Senior Fellows) during each review period or complete the written exam, and attest that their license/credential (or their supervisor’s license/credential) has not been suspended, investigated, or revoked.[53]

Neuroplasticity

In 2010, a study provided some evidence of neuroplastic changes occurring after brainwave training. Half an hour of voluntary control of brain rhythms led in this study to a lasting shift in cortical excitability and intracortical function.[54] The authors observed that the cortical response to transcranial magnetic stimulation (TMS) was significantly enhanced after neurofeedback, persisted for at least 20 minutes, and was correlated with an EEG time-course indicative of activity-dependent plasticity.[55]

See also

References

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  2. ↑ http://www.braintrainuk.com/wp-content/uploads/2013/07/How-AAP-reached-conclusion-other-recent-evidence-July-2013-V3.pdf
  3. ↑ Scottish Intercollegiate Guidelines Network (2009). Management of attention deficit and hyperkinetic disorders in children and young people: A national clinical guideline. NHS Quality Improvement Scotland. p. 24.
  4. 1 2 3 Dobie C,; Donald WB; Hanson M; Heim C; Huxsahl J; Karasov R; Kippes C; Neumann A; Spinner P; Staples T; Steiner L. (2012). Diagnosis and Management of Attention Deficit Hyperactivity Disorder in Primary Care for School-Age Children and Adolescents. Institute for Clinical Systems Improvement. p. 41.
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  44. ↑ Hammond, D. Corydon. "Neurotherapy also called Neurofeedback or EEG Biofeedback". Applied Neuroscience Society of Australasia. Applied Neuroscience Society of Australasia. Retrieved 19 April 2016.
  45. 1 2 3 Sokhadze, Tato M.; Cannon, Rex L.; Trudeau, David L. (Mar 2008). "EEG Biofeedback as a Treatment for Substance Use Disorders: Review, Rating of Efficacy, and Recommendations for Further Research". Appl Psychophysiol Biofeedback 33 (1): 1–28. doi:10.1007/s10484-007-9047-5. PMC 2259255. PMID 18214670. Retrieved 19 April 2016.
  46. ↑ Reel, Justine J. (2013). Eating Disorders: An Encyclopedia of Causes, Treatment, and Prevention. ABC-CLIO. p. 300. ISBN 978-1-4408-0058-0.
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  48. ↑ http://www.bfe.org/
  49. ↑ Neblett R., Shaffer F., Crawford J. (2008). "What is the value of Biofeedback Certification Institute of America certification?". Biofeedback 36 (3): 92–94.
  50. ↑ Washington State Legislature WAC 296-21-280 Biofeedback Rules.
  51. ↑ Gevirtz, R. (2003). The behavioral health provider in mind-body medicine. In D. Moss, A. McGrady, T. C. Davies, & I. Wickramasekera (Eds.). Handbook of mind-body medicine for primary care. Thousand Oaks, CA: Sage Publications, Inc.
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  54. ↑ Science Daily
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