EEG Biofeedback Training for Chronic Pain
EEG biofeedback has been shown to be very helpful with chronic pain. Since these results may be somewhat unexpected, they present perhaps the best challenge to our understanding of the mechanisms of EEG biofeedback. When we regard pain sensors alongside other sensory systems, such as vision and hearing, we observe a unique distinguishing characteristic. In the general case, when human sensory systems are presented with a constant stimulus there is a gradual decrease in response to that stimulus. The only known exception to this general rule is the body’s pain response to persistent challenge. In this case, the response is to gradually *increase* sensitivity to the stimulus, i.e. a lowering of the local pain threshold. Thus pain can survive even when the original provocation is removed, resulting in chronic pain. A self-sustaining interaction takes place between the cortex and the apparent source of the pain, perpetuating the sensation of pain. This explanation by no means denies the reality of the pain experience.
It simply defines it in terms of a self-reinforcing, self-sustaining activity involving the brain as well as the “periphery”. That is, the brain defines what is to be perceived as painful.
A striking correlation has been observed between the occurrence of chronic pain and a history of abuse or trauma in childhood. One study found that such abuse was present in as many as 85% of cases of chronic pain. Clearly, then, more than a “purely” physiologically-based phenomenon is at issue. Why, then, should a technique which appeals strictly to the underlying physiology be effective? We conjecture that there is a mutual relationship between the phenomenon of chronic pain and a state of depression. The physiological state of depression (to which the person may be susceptible due to the prior abuse) may bring in train disregulation of the pain threshold; or the causal chain may go the other way: the persistence of chronic pain may bring about a chronic state of depression, to which the person is particularly vulnerable. In any case, we observe symptoms characteristic of underarousal. The EEG training is presumptively effective in remediating the chronic underarousal condition, effecting a normalization of mood and of the pain threshold. Effectively, then, the brain has simply recalibrated the pain threshold. It no longer interprets the incoming stimuli as being sufficient to constitute “pain”.
This view may, however, be an oversimplification. Frequently, persons undergoing the EEG training for chronic pain will, after a few sessions, experience vivid recollections of long-suppressed traumatic memories. This occurs with such regularity that we always encourage persons undergoing the EEG training for chronic pain to undergo concurrent therapy as well, in order to deal with what comes up. In the larger view, then, the remediation we effect may involve dealing comprehensively with the larger, underlying issues which manifest in chronic pain and in depression.
Undoubtedly both mechanisms play a role during the full course of EEG training. In case there is any doubt, however, about the specific role and benefit of EEG training in remediation of chronic pain, it should be said that the two mechanisms operate on very different time scales. Reports of alleviation of pain can occur even within the first session; further progress can be charted from one session to the next. The surfacing of suppressed memories may not take place until sessions 6-15, and the therapeutic benefit of adjunctive therapies not until after that. Hence, there is clearly a role implied for the EEG training.
It is noteworthy that the field of pain management has seen the first truly comprehensive, multi-disciplinary approach emerge, one in which biofeedback plays an indispensable role. Up to the present time, the predominant use of biofeedback has tended to be relaxation training. The implications of our work with EEG training to remediate chronic pain are that emphasis should perhaps be placed more on the achievement of regulation and control, rather than relaxation.