Effects of rapid eye movement (REM) sleep deprivation on shock-induced fighting☆☆☆

Abstract

Abstract The effects of REM sleep deprivation on shock-induced fighting behavior in rats were studied in three experiments. The experimental animals were selectively deprived of REM sleep by maintaining them on a small pedestal surrounded by water. One control group was maintained under similar conditions except that REM sleep was permitted to occur, while a second control group was conventionally housed. Fighting behavior was elicited by administering a train of brief electric shock pulses at five intensities to pairs of rats. In Experiment 1, fighting behavior was studied before, during, and after REM sleep deprivation. Experiment 2 replicated the first study except that fighting was not studied during the treatment period. REM sleep deprived animals showed dramatic increases in fighting frequency which persisted even after prolonged sleep recovery. In Experiment 3, the experimental group had a history of four previous cycles of REM sleep deprivation and recovery before fighting behavior was studied. The animals previously deprived of REM sleep fought significantly more than their controls. In Experiments 4 and 5 the adrenocortical stress response was examined in REM sleep deprived and control animals. Results indicated statistically significant but small changes in plasma corticosterone levels as a result of REM sleep deprivation.