Pain is a subjective feeling that can be influenced by sensory, affective, and cognitive factors. Chronic pain can have a widespread impact on overall brain function, and both cognitive and psychological factors play key roles in the development and management of pain.
Patients with long-term pain often have structural and emotional impairments associated with cortical regions of the brain that are linked not only to pain itself, but also to other disorders that develop in association with chronic pain, for example, depression, anxiety and sleep disturbances. Patients with chronic pain often receive long-term pharmacological treatment; but there are a number of drawbacks mainly due to the undesirable side-effects that often arise with a continued use of analgesic drugs. There is a constant search for better pain management options, including non-pharmacological approaches. In the last decades, neurofeedback has been gaining ground as a potentially successful option.
is a form of biofeedback. Biofeedback was born from the observation that one can control and manipulate certain bodily functions associated with the autonomic nervous system by being aware of them. Using instruments that measure physiological activity such as heartbeat, breathing, muscle activity, or skin temperature, a subject can receive fast and accurate information regarding those functions, and in turn, and with adequate training, manipulate those functions which can lead to changes in thinking, emotions, and behavior. Over time, these changes can become long-lasting, enduring even without the continued use of monitorization instruments.
Neurofeedback, is simply biofeedback techniques that are applied to the brain. Neurofeedback, also known as EEG-biofeedback, uses electroencephalograms (EEG) to monitor brain waves, producing a signal that can be used as feedback to learn how to self-regulate brain functions. Recently, other monitoring techniques have begun to be applied, namely functional magnetic resonance imaging (fMRI) biofeedback.
For decades, it has been known that with adequate training, brain waves can be controlled. Intellectual activity induces fluctuations in the brain’s bioelectric activity that can translate into neurophysiological changes. By understanding the association between the bioelectric activity of different brain areas and the associated cognitive, emotional, behavioral, or even pathological processes, neurofeedback can allow the modification of those specific processes.
Neurofeedback has proven useful in inducing relaxation and attention, in enhancing creativity, and as a therapy for a number of conditions – sleep disorders, epilepsy, depression, anxiety, language processing, or enhancement of perception and learning. Another context in which neurofeedback has shown interesting effects is chronic pain.
The psychological factors that influence pain perception have the ability to modify our body’s biochemical processes. Thoughts can have a direct impact on these processes and potentially produce analgesia. In fact, there is evidence indicating that cognitive control of pain can have a direct effect on opiod activity, stimulating the production of endorphins.
Another mechanism through which neurofeedback can modulate pain is the regulation of the emotional component of pain. The frontal cortex is associated with the feeling of unpleasantness associated with pain. Neurofeedback training applied to this region of the brain has been found to be able to affect levels of pain in patients with acute and chronic pain syndromes, leading to an increased pain tolerance.
Chronic pain can also induce changes in the functional organization of the brain. Neurofeedback can allow the control of pain by altering the connectivity between brain regions, thereby inducing long-lasting changes in neuronal networks that can counterbalance the changes induced by chronic pain.
Indeed, clinical data has demonstrated the effectiveness of neurofeedback therapy in a number of chronic pain conditions: it can decrease headache intensity, being particularly effective in children and adolescents, as well as migraine and pain associated with fibromyalgia. Neurofeedback can also be effective in post-operative pain as well as cancer pain.
During the last decades, neurofeedback training approaches and protocols have been steadily improving, along with its successful effects. As new methods arise, it is likely that neurofeedback can gain awareness and importance as a non-pharmacological therapy for a multitude of disorders. fMRI imaging, for example, can be a great upgrade for this therapy by allowing the detection of brain areas affected by chronic pain, and consequently allowing a more targeted intervention.
The take-away is: If one can learn to directly control the activation of specific brain regions, one can potentially be able to control neurophysiological mechanisms that may help in the treatment of other diseases.