How does neurofeedback work?

An effective intervention into any system is to introduce feedback of the signal to be changed into the system This allows the system to self regulate, like the heating or cooling system in a house as a simple analogy. The models of how this works vary from systems theory, to anatomical/structural models, learning theory, even non-linear dynamics or “chaos theory”. The organic models have some measurable validity, with the observed expansion of cortical areas dedicated to the structures utilized in tasks. Another observation supporting this model is the dendritic density increase in the cortex utilized in learned tasks. There are even reports recently of memory or ‘long term potentiation’ being predicted by the electrophysiologic brain state measured at the time of the perception to be recalled (Wagner et al., Science, August 1988) The learning theory models have learning curve data to show the stages of the acquisition of the skill of volitional control over the autonomic activity with NT. They also predict the effect on efficacy of the sessions’ scheduling to shorten the total treatment times; massing the initial sessions and stretching out the later session’s intervals. The systems theorists suggest the mere introduction of feedback may initiate self regulation. This is seen with the audible heart beat normalizing the inter-beat interval, without any instructions to the subject. The most controversial systems theory being the “chaos” theoreticians, who vary in opinion. Some chaos theoreticians in this field will say the anatomically specific electrode site selection in NF is irrelevant ( Brown et al., 1998 SSNR), with others saying the site selection is critical for optimizing the training in NF (Thatcher, personal communication 1998). Some theoretical discussions even state that the purturbation of the system from feedback acts to chaotically restabilize the system independent of the need to follow out a learning curve of further treatment, just expose the system to the chaos of feedback and that is all that is needed (Schore, 1997). The bottom line is they all are theories, or perspectives with testable hypotheses associated with them. Many theories are not mutually exclusive of others, so the research proceeds with various, sometimes mutiple perspectives. The complexity and diversity of the models and opinions attests to the interdisciplinary nature of this field. The most conservative critics would suggest placebo effect and experimenter effects as the sole forces at work in NF. This too is a testable hypothesis, one which is having an increasing difficulty explaining the observed results of the research found in peer reviewed publications.