Diurnal Rhythms in the Nest-Building Behaviour of Female Mice
Abstract:Two experiments are described. In the first, five female mice of strain RAP, maintained on a LD 12:12 light cycle, were trained to key-press on a CRF schedule, using paper strips as reinforcement. They were then allowed continuous access to the key for eleven days, their nests being removed daily in the middle of the light period, and numbers of key-presses and reinforcements were recorded hourly. All subjects showed a marked diurnal rhythm in responding, with peaks at the beginning, middle and end of the dark period. The middle peak was substantially larger than the other two in three subjects. Responding was rare in the light period, except for a brief bout immediately after nest removal. Responding at this time ceased to occur when the nest was not removed. In the second experiment, 16 mice were allowed access to hoppers of paper for two hours per day, at the beginning, middle or end of the dark period, their nests being removed two hours prior to each session. More paper was taken at the end of the dark period than at the beginning, but the amounts taken at the end and in the middle of the dark period did not differ significantly.
Document Type: Research article
Publication date: 1974-01-01