To the Editor:
—In the editorial on sleep and its relation to complete muscular relaxation (The Journal, October 20, p. 1366) you stated that "we have failed, heretofore, to realize the extent to which the impulses pouring into the brain come from the muscles, tendons and joints, proprioceptive impulses as they are often termed, in addition to the visual, auditory and tactile sensations that usually play on the sensorium."Observations have been made and recorded that have formed the nucleus of interest in the work of my associates and myself for many years. Relaxation has been studied in connection with sleep, insomnia and nervous states (Use of Relaxation in Hypertensive States, New York M. J.111:419 [March 6] 1920; Reduction of Nervous Irritability and Excitement by Progressive Relaxation, Tr. Sect. Nerv. & Ment. Dis. A. M. A., 1920, p. 17; Treatment of Nervous Irritability and Excitement, Illinois M. J.