It is known that for patients a chronic pain in the back, without actual problems in the back anymore, continues although the physiological reason for the pain is not present anymore. The proposal is that this pain originates in the brain.
The TGD interpretation is the same as in the case of phantom limb. The pain would not be imagined but would be real pain as a sensory memory of the pain, just as in the case of phantom limb. We indeed have sensory memories: long ago it was learned that the stimulation of parietal regions of the brain created sensory memories as direct experiences. The memory feats of some idiot savants are very probably based on sensory memories. Instead of a verbal representation, they have a direct sensory experience about say landscape or a music piece.
The view about memories provided by zero energy ontology is that they are in space-time where the original painful event occurred and involve a communication with the brain and body of the geometric past. This is essentially seeing in the direction of geometric time: time reflection takes place from an appropriate region of the brain or MB. Therapy might allow us to get rid of these sensorily painful memories in the same way as it allows us to get rid of psychologically painful memories.
For a summary of earlier postings see Latest progress in TGD.
For the lists of articles (most of them published in journals founded by Huping Hu) and books about TGD see this.