The reinforcement process in the brain has positive and negative aspects. Negative reinforcement is defined psychologically (and somewhat differently than lay people think), as removal of a painful or noxious state by the behavioral action of the person.

Hence taking an aspirin to relieve a headache is called negative reinforcement in this context.

Much of reinforcement according to the expert I listened to involves less than what we would call "pleasure". Relieving hunger, for example, is just a reduction in some stimulus from our body to eat something. Eating something "decadent" however may cross over to pleasure.

Pain relief, for chronic pain is not going to be "pleasureable" therefore, as it is being done to remove a painful stimulus and not create euphoria or a "high".

This is not to say that some people here on PN should not consider heavy duty opiate therapy for their PN. Some PNs are so painful, there is no quality of life possible past a certain point. Deciding what to do is a personal decision, and if you and your doctor decide heavy duty pain relief is necessary, you will have to do it or at least consider it.

The net is really full of papers on habituation, reinforcement and other psychological investigations on this subject.

For the most part today, the thrust of both seminars I attended was in lifestyle interventions. Obesity and weight gain, being the primary target, and not chronic pain.