Results were obtained from comparative studies of skin pain sensitivity (pain thresholds) using focused ultrasound in 51 healthy men and 101 patients with neurasthenia. Neurasthenia is a natural “model” of chronic psychoemotional stress, and patients showed a reduction in the pain threshold which was not accompanied by a reduction in the threshold of sensitivity to tactile stimulation. A reduction in the pain threshold, reflecting a weakening of central descending tonic inhibition, was probably due to a reduction in the activity of the brain’s opioid system during long-term psychoemotional stress. Analysis of the relationships between the pain sensitivity threshold and pain syndromes suggests a role for changes in the nociception system in chronic psychoemotional stress, as part of the mechanism of pain formation.
Ashkinazi IYa, Vershinina EA