REM sleep deprivation and food competition in male rats

As a test of the hypothesis that REM deprivation lowers the threshold for “motivational” behaviors, 17 male rats that had been REM deprived were tested against 17 non-deprived male rats in three series of food competition tests, i.e., an immediate, a 3 hr, and a 48 hr series of posttreatment tests. The results provide support for the hypothesis that REM deprivation generally activates “motivational” behaviors, in that the REM deprived animals won more frequently as had been predicted. However, the response gradients of the two groups over the course of the postteatment test series did not conform to prediction. These data are discussed together with the results of other studies which suggest that perhaps the list of behaviors which have been subsumed under the category—“motivational behaviors” is too broad to be of real scientific value.