The purpose of the study was to examine vegetative innervation of the pupil in different diseases associated and not associated with vegetative disorders. In addition to the ++clinico-neurological method, the main method of examination was to study the pupillary cycle (determination of the time of the pupillary cycle (TPC) with the aid of a slit lamp). Fifty healthy test subjects and 262 patients suffering from different somatic and neurologic diseases were examined. The patients were divided in 9 clinical groups: spinal amyotrophy, neural Charcot-Marie amyotrophy, Guillain-Barre syndrome, diabetes mellitus, thyrotoxicosis, hemicrania, Raynaud's disease, idiopathic hyperhidrosis, vegetative crises. The data obtained demonstrate varying grades of the rise of the TPC in the indicated diseases, which reflects varying degrees of vegetative innervation of the pupil insufficiency. However, no well-defined correlation was obtained between the intensity of the psychovegetative syndrome and the TPC. Therefore, it has been shown that the method of determining the TPC is unsophisticated and noninvasive and can be successfully used in different forms of pathology to identify vegetative insufficiency at different stages of the disease.