Does Neurofeedback really work?

Post traumatic stress disorder and brain injury patients may benefit

/ Author:  / Reviewed by: Joseph V. Madia, MD

Scientist have made amazing progress measuring the electrical fields of the brain, especially in recent decades.

Does medical science now know enough to be able to use that knowledge to change the brain's electrical state, so that patients with medical conditions benefit?

For the better part of a century, researchers and clinicians have been able to put sensors on a patient's scalp to measure how the brain's 100 billion neurons generate electrical fields. The patterns produced when these fields are recorded by the sensors as waves are known as an electroencephalogram, or EEG.

These electrical fields that the brain generates are exceedingly complex, only very provisionally understood by biophysicists and neuroscientists.

Physicians and other clinicians nevertheless have been able to find medically useful patterns in the data produced by this measurement technology. There are clinically important correlations between the cognitive and psychological states of the patient and the waves their brain produces.

Can these electrical waves that are generated by a patient's brain be presented back to the patient for therapeutic purposes? The jury is still out, but there are data suggestive that some patients do in fact benefit. The search is underway to test the medical utility of these technologies, labeled "neurofeedback or "neurotherapy".

What is neurofeedback/neurotherapy?

Various psychiatric and neurological disorders have been associated with differences in brainwaves. Generations of doctors have been trained to recognize and interpret the medical significance of various peaks and troughs on an EEG chart, and now computers support ever more sophisticated analysis of this data.

EEG's have well known uses for diagnosis. Abnormalities in activation level of regions of the cortex, the part of the brain that is especially associated with higher mental functions, can be detected quite well with EEG.

EEG, in conjunction with specialized software for analysis, gives clinicians a tool for determining the relationship between brain region abnormalities and cognitive, emotional, perceptual and behavioral problems.

As EEG technology for diagnosis of mental and neurological disorders has become more sophisticated and powerful, a parallel technology called "biofeedback" that uses a patient's own biological rhythms for therapeutic purposes was being developed.  

For a number of decades there has been interest by psychologists and others in using biological waves from a patients as a form of therapy. Wave data is recorded from the rhythmic pulsing of systems in the body, such as with heartbeat, and the data can be presented to a patient using a computer.

EEG rhythms now can be fed into a computer, then re-presented as visuals or sounds to a patient as "feedback" for therapeutic purposes. Psychologists have been intrigued by the potential benefits of this feedback for relaxation, stress relief or heightened attention.

Some researchers were led to wonder whether EEG technology could be modified to induce electrical changes inside the brain. These biofeedback technologies have been named "neurotherapy" or "neurofeedback. Other labels include "EEG feedback therapy", "bioneurofeedback" and so forth.

Clinicians now can present feedback from EEG waves to patients as a tool for stimulating their brains, hopefully treating conditions such as attention deficit disorder, post-traumatic stress disorder or traumatic brain injury.

Neurotherapy as a tool for clinicians: does it beat placebo?

Does neurotherapy or neurofeedback really work? Do patients benefit if doctors use EEG-based biofeedback to stimulate areas of the central nervous system associated with depression, attention deficit disorder, or traumatic brain injury?

The evidence is mixed, but there are data that suggests post-traumatic stress disorder and traumatic brain injury patients may benefit.

One study by David Nelson, Ph.D and Mary Etsy, Ph.D, using the Flexyx Neurotherapy System, measured how seven Afghanistan/Iraq war veterans who suffer from traumatic brain injury and posttraumatic stress disorder symptoms responded to neurotherapy. The system allows clinicians to use an electrical apparatus and biofeedback to stimulate the patient's brain, with the hope that it will change the electrical state of certain brain networks.

The authors report in a 2012 article in the Journal of Neuropsychiatry and Clinical Neurosciences that the patients who were given this neurotherapy treatment showed "significant decreases in bothersome neurobehavioral and posttraumatic stress symptoms."

If a patients feel better after biofeedback sessions, does this not constitute proof that the therapy works? It does not.

It is not enough that patients seem to respond positively. In order to demonstrate that the neurotherapy actually caused the measured benefits, a different sort of methodology is needed.

Patients may actually be responding positively because of an enigmatic phenomenon known as the "placebo effect". For reasons that are not clear, a patient's belief that a drug or therapeutic intervention works can produce measurable benefits in pain reduction, lessening stress, depression or numerous disorders.

For a drug or treatment with a device to be rigorously assessed as medically useful, it is not enough to administer it to patients and get them to respond that it was helpful or therapeutic. The change in the patient's state could be mostly or completely from the placebo effect.

Therefore, a sham treatment or some other means is needed to determine whether neurotherapy "beats placebo", i.e, provides therapeutic benefits beyond what could be produced by a patient's expectations or belief that the therapy will help them.

A particular set of methodologies are required to determine the real efficacy of the neurotherapy. To tell the difference between the therapeutic benefit generated by the neurotherapy treatment vs, patient's expectations and beliefs, researchers measure how patients respond to a "sham" intervention as well.

This involves coming up with a control group of patients who are matched to the treatment group in terms of gender, age, and so forth. This second group is told they are getting the real neurotherapy system, but are instead hooked up to a bogus neurotherapy device.

All other conditions and actions between this control group, and the group who gets the real treatment, must be kept the same. This allows researchers to tell whether any benefits that result can be shown to be based on the patient's belief in the treatment (the placebo effect) or are in fact from the neurotherapy treament.

Studies that measure placebo with a control group as well as those patients who get the real neurotherapy intervention can thus make a much more rigorous measurement about the real clinical usefulness of neurotherapy. Most of the available studies to date have not had a control group however, so their real-world clinical relevance is more modest.

Patients in studies of neurotherapy may in fact be benefiting. More rigorous studies that use control groups will be needed to determine the real clinical usefulness of the approach.

Conclusion

Neurotherapy involves one of a number of approaches that capture the rhythmic waveforms of an individual's brainwaves in order to represent this as a form of potentially therapeutic biofeedback. The captured waves are retransmitted to the central nervous system of the patient via a neurofeedback device.

Some patients who use this technology seemingly improve their attention deficit disorder, traumatic brain injury or other condition. There are a number of studies that claim these individuals do indeed benefit.

However, in order to demonstrate that the neurotherapy actually caused the measured benefits, studies that employ "sham" treatments are needed. This involves getting patients with similar conditions and background and testing them with a bogus neurotherapy device alongside the patients who get the real intervention.

neurotherapy may be benefiting, more rigorous science will be needed to determine the real clinical usefulness of the approach.

Reviewed by: 
Review Date: 
July 19, 2012