Caffeine/sleep-deprivation interaction in mice produces complex memory effects

BACKGROUND Sleep deprivation negatively impacts memory, causing deficits in memory processes. Of interest is any agent that can offset such deficits. Mice were given varying doses of caffeine for 14 days and then deprived of sleep for 6 hours by the 'gentle handling' method. Memory was assessed using the Novel Object Recognition Test and Y maze alternation. PURPOSE The study was designed to ascertain the impact of varying doses of caffeine combined with total sleep-deprivation on spatial and non spatial memory in mice. METHODS Adult Swiss Webster mice of both sexes were assigned to six groups viz., vehicle (distilled water), or one of five selected doses of caffeine (10, 20, 40, 80 and 120 mg/kg) for 14 days via the oral route. Open field novel object recognition test and Y maze spatial working memory tests were carried out on day 14. Results were analysed using multi-factorial ANOVA followed by Tukey HSD test and expressed as mean ± S.E.M, with p values less than 0.05 were considered statistically significant. RESULTS Novel object recognition tests (NOR) revealed that pre-training and pre-test sleep deprivation and caffeine combination impaired non spatial and spatial memory in male and female mice. CONCLUSION The study shows the complex interactions with memory that may arise when total sleep deprivation is superimposed on caffeine administration.