202

intermittent tapping. Progressively increasing the stimulation frequency increased the rate of tapping and then evoked flutter and then vibration of gradually increasing intensity. Stimulation of type I slow adapting (SAI) fibers evoked a sensation of pressure which increased in force with increased stimulation frequency. Stimulation of type II SA fibers (SAII) did not evoke any recognizable sensation.

PSYCHIATRY

Psychiatry and the cervical sprain syndrome, - H. Merskey (Dept. of Education and Research, London Psychiatric Hospital, P.O. Box 2532, Terminal A, London, Ont, N6A 4H1, Canada), Canad. med. Ass. J., 130 (1984) 1119-1121.

This editorial discusses the relationship between injury, compensation, the whip-

lash (cervical sprain) syndrome and also the post-concussional syndrome. It is noted that expert evidence tends to favour the side which calls it. Nevertheless, follow-up

studies have repeatedly shown that many patients fail to get better from compensa- ble symptoms even after the legal proceedings are finished. An accumulation of other evidence is also listed to suggest that there is a significant organic basis both for the cervical sprain syndrome and the post-concussional syndrome after minor head injury. Psychiatric changes which develop are often secondary to pain and

disability.

The effects of dietary tryptophan on chronic maxillofacial pain and experimental pain tolerance. - S. Seltzer, D. Dewart, R.L. Pollack and E. Jackson (Ma~llofacial Pain

Control Center, School of Dentistry, Temple University Hospital, 3223 N. Broad Street, Philadelphia, PA 19140, U.S.A.), J. psychiat. Res., 17 (1982/83) 181-186.

This study investigated the effects of daily administration of 3 g of tryptophan in conjunction with a high carbohydrate, low fat, low protein diet on chronic maxillofa-

cial pain, experimental pain thresholds, and anxiety and depression. In a double-blind

study, 30 chronic pain patients were randomly assigned to a tryptophan or placebo group. At the initial appointment and 4 weeks later, the patients’ subjective ratings of their pain were recorded, electrical tooth pulp stimulation was used to measure

pain thresholds, and psychological tests of depression and anxiety were adminis- tered.

Over the 4 weeks of the study, there was a greater reduction in reported clinical pain and a greater increase in pain tolerance threshold in the tryptophan group than in the placebo group. The group did not differ in anxiety and depression - for all subjects there was lowered depression and anxiety over the 4 weeks of study.

Sleepreiated myoclonus in rheumatic pain mutation disorder (fibrositis syndrome) and in excessive daytime somnolence. - H. Moldofsky, C. Tullis, F.A. Lue, G.

Quance and J. Davidson (Edith Cave11 Wing, Toronto Western Hospital, 399 Bathurst Street, Toronto M5T 2S8, Canada), Psychosom. Med., 46 (1984) 145-151.

A new syndrome, rheumatic pain modulation disorder (RPMD) (‘fibrositis syn- drome’) with sleep-related myoclonus (involuntary periodic leg movements) is de-