◆ SpookStack

Approved For Release 200: 04/ABc 1ElFROP96-00788R001300020001-6 $T-CS-—01-169-72 July 1972 increasing progressively in intensity until the midday break. For some, the 30 minute break at noon restored work capacity and lessened the severity of the headache. Considerable exhaustion was experienced by most subjects by the end of the workday. Besides the marked fatigability and tiredness the examinees complained of a constant feeling of general weakness and vertigo with dimming of vision occurring by noon, at the end of the workday, under physical or mental strain and in stuffy rooms. These sensations caused loss of consciousness in some individuals. 2. (VU) Another effect of ultrasound was disturbances in sleeping patterns. The need for sleep was felt by one group during actual work, before the noon break, or toward the end of the work day. Some individuals were overcome by drowsiness during short pauses in work and in longer pauses fell asleep standing up or in other normally uncomfortable positions. In rare cases daytime drowsiness was of the nature of a hypnagogic state, during which the individuals continued to be oriented in their surroundings, hear speech, follow the industrial process, and at the same time, sleep with clear dreams. Changes in nocturnal sleep were also reported. Thirty- eight per cent of the workers complained of drug-like heavy, dream- less sleep, while another group (18%) slept superficially and inter- mittently with difficulty in falling asleep and, in some cases, with oppressive dreams. 3. (U) Other reported effects were morbidly sharpened perception - of ordinary sounds during off-duty hours, leading to sleeplessness and the opposite extreme, in which one worker reported the sensa- tion of "wanting to sleep day and night," even during the workday. Heightened irritability was detected in 30 persons, while in 15 others, intellectual impairments were found. These included pro- nounced loss of memory (especially for current events), decreased perception, and inability to master new material. 4. (U) During clinical examination of this group of workers the investigators noted lassitude, apathy and retardation of movements and reactions. The examinees rarely expressed their complaints themselves, but more often had to be prodded verbally in order to elicit information. Replies to questions were monsyllabic and conversational initiative was lacking. 5. (U) In other studies conducted by the Institute of Hygiene imeni Erisman, Yefimov (276) reported findings including weakeniny of the sense of smell and decreased taste sensations as well as certain disturbances in digestion. Of the gastrointestinal symp— toms, the most frequently noted were poor appetite, nausea and a tendency toward constipation. In some cases these symptoms were 97 UNCLASS IFIED Approved For Release 2003/09/10 : CIA-RDP96-00788R001300020001-6