[Effect of emotional stress on sleep dynamics in cats].

Emotional stress was developed in cats by putting them in one cage with dogs for 24 hours. Then the 24 hours sleep-walking cycles records revealed prolonged REM stage in day time or at night in five animals out of seven, and in six animals a general increase of REM sleep duration over 24 hours. Simultaneously, in six animals the length of drowsiness and of deep slow-wave sleep stages was reduced. Increased overall sleep duration in the 24 hours was recorded in five cats. Sleep changes dynamics analysis reveals three stages: 1) sharp shift of all sleep parameters--27%, 2) deviation in sleep parameters--34% and 3) returning to basic sleep parameters--in 38%. The conclusion is drawn that sleep disorders may be used as an index of higher nervous activity disturbance in waking state.