Neurofeedback (NFB) defines an operant conditioning method that instructs individuals to alter their brain-state, primarily by introducing incentives and making them aware of their own subconscious responses.[1] Neurofeedback techniques coupled with spectral analysis have been demonstrated to alter cognitive performance when targeted at increasing or decreasing the prevalence of specific bands of frequency in an individual’s EEG. Classically, neurofeedback training has consisted of sessions administered in controlled laboratory setting. This project endeavors to reinforce the notion that such principles can be transplanted to a home setting and applied personally.

       The concept of neurofeedback originated from the larger field of biofeedback, training behavior based on an individual’s action biology. D.W. Shearn explored an early example of biofeedback in 1962, when he trained human subjects to consciously lower their heart rates by shocking them with electricity when elevated heart rates were detected.[2] A.A. Marinacci was the first to use biofeedback as a medical treatment by providing Electromyography-based (EMG) feedback to help victims of polio, strokes, and other conditions that impair proprioception.[3]

       The concept of neurofeedback dates back to studies in the 1960’s and 1970’s wherein subjects were trained to go into an alpha state, a brain-state dominated by 8-12 Hz oscillations of activity and connected with wakeful relaxation. However, the idea of using neurofeedback in practical applications arose in the late 1980’s. Two patents filed in 1990 and 1989, one by J.V. Hardt[4] and another by M.E. Ayers[5], describe EEG-based systems for providing neurofeedback with the intent of training users to control neural activity voluntarily. Such systems would translate patterns of EEG measurements —specifically, the relative proportions of theta (4-7 Hz), beta (12-30 Hz), alpha (8-12 Hz), and mu (8-13 Hz) waves in the recordings — into physical cues such as vibration, sounds, or colors. Over time, users would learn to control these physical cues by achieving specific patterns of neural activity, brain-states.

        In 1993, M.A. Tansey filed a grant to design a neurofeedback system with the ability to be reprogrammed based on individual users’ brain activity[6]. In Tansey’s system, multiple EEG recordings would measure users’ neural activity during specific mental states such as concentration, drowsiness, or distraction. Such a system could correlate EEG patterns with more complex mental processes, ones that often vary based on a subject’s individual patterns of thought.

        Recently, EEG-based neurofeedback has found use as a treatment for learning and mental disorders such as attention deficit-hyperactivity disorder[7] and depression.[8] Such conditions are characterized by excessive and intrusive brain-states such as lack of focus, anxiety, and obsessions. The discovery of specific patterns of neural activity in these conditions allows neurofeedback systems to alert patients of unwanted brain-states and train them to curb such neural activity over time.

 

 

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[1] Angelakis E, Stathopoulou S, Frymiare J, et al. EEG neurofeedback: a brief overview and an example of peak alpha frequency training for cognitive enhancement in the elderly. The Clinical Neuropsychologist 2007; 21:110-29

 

[2] Shearn D. W. Operant conditioning of heart rate. Science 137 (3529): 530–531 (1962).

 

[3] Marinacci A. A. Lower motor neuron disorders superimposed on the residuals of poliomyelitis. Value of the electromyogram in differential diagnosis. Bulletin of the Los Angeles Neurological Society 25: 18 (1960).

 

[4] Hardt, JV. EEG biofeedback method and system for training voluntary control of human EEG activity. United States Patent Application US 4928704 A. Application filed 31 Jan., 1990.

 

[5] Ayers, ME. Electroencephalic neurofeedback apparatus and method. United States Patent Application US 4919143 A. Application filed 14 Jun, 1989.

 

[6] Tansey, MA. Electroencephalic neurofeedback apparatus and methods. World Intellectual Property Organization Grant Application WO1994005201 A1. Application filed 2 Sep., 1993.

 

[7] Bakhshayesh AR, Hänsch S, Wyschkon A, Rezai MJ, Esser G. Neurofeedback in ADHD: a single-blind randomized controlled trial. European Child & Adolescent Psychiatry 20 (9): 481–491 (2011).

 

[8] Linden DE, Habes I, Johnston SJ, Linden S, Tatineni R, Subramanian L, Sorger B, Healy D, Goebel R. Real-time self-regulation of emotion networks in patients with depression. PLoS One 7 (6): e38115 (2012).