Pleasure and pain are interoceptive (internally focused and experienced) senses that are critical to survival. The prime directive of all living things is to pursue pleasure and avoid pain. Persistent pain is so vexing, because it is, by definition, unavoidable. It negates pleasure perception in most people suffering from it. Pleasure and pain perception share many of the same circuits and the same cells. Neurotransmitters, however are opposites, with pleasure neurotransmitters including GABA, endorphins, oxytocin, anandamide, dopamine and adenosine and pain neurotransmitters including Glutamate, Substance-P, Calcitonin Gene Related Peptide and Adenosine Triphosphate. Theoretically, as a corollary to pain blocking pleasure, if pleasure neurotransmitters flood the same circuits and brain regions, pain neurotransmitters should be counteracted.
Recently, the field of hedonics has played an increasingly prominent role in neuroscience and neuroimaging literature. Work by Smith, Berridge and Kringelbach, among others has steadily clarified the importance of pleasure and the clear distinction between pleasure (liking) and addiction (wanting). This has lead to an understanding of the anatomic, physiologic, electrical and functional aspects of pleasure. Functional imaging studies have delineated the relationship of pain and pleasure, even providing evidence of the pleasure of pain relief, itself.
The idea of replacing pain with pleasure is an enticing one, made all the more intriguing by contemplating the three rules of neuroplasticity (1. What is fired is wired; 2. What we don’t use we lose; 3. New synapses require breaking old synapses), the commonalities of pleasure and pain brain activity and the biological imperative of pursuit of pleasure and avoidance of pain. We worked with our patients on these principles, instituting various approaches, including constructing a gratitude list, a comparison of pleasure to pursue and pain to avoid, gathering a personal pleasure pack, going on a one day pleasure hunt and using soothing and pleasing sensory stimulation. The results have pointed out that in people suffering with chronic pain, pleasurable experience is transformative. While researchers struggle with the definition of happiness, we have found that the experience of happiness is that of balancing soothing and stimulation.
We have conducted a case series on sound and vibration, showing excellent pain relief. As mentioned in the sound and vibration areas of Research, we plan to institute randomized trials and functional imaging to see what regions of the brain are stimulated and how that correlates with pain relief and pleasure induction. We also want to study the phenomenon known as “flow,” in which a person becomes so pleasurably involved in an activity, that they lose their sense of being separate from it. Furthermore, a major research target to control persistent pain is establishing practical clinical applications of the balance between hedonia (pleasure) and eudaimonia (a meaningful, well-lived life), as described by Berridge and Kringelbach. The endocannabinoid system is another area of intense interest for hedonic research, and new research showing that this system plays a far more extensive role in many brain and immune system based activities than previously offer up many interesting research possibilities we will be exploring.