Fig. 7
IntelliCage daytime & nighttime activity and preference learning in ELP mice. ChR2-flfl and Avil-ChR2 mice were exposed to blue light in a chamber on postnatal day P1-P5 together with the Cre-negative blue-insensitive mother. IntelliCage observations started at 30 weeks of age and lasted 9 weeks. The experiment included n = 15 ChR2-flfl and n = 16 Avil-ChR2 female mice. Mice were trained in sequential tasks of increasing difficulty. Tasks were free adaptation (FA), nosepoke adaptation (NP 3 corner, NP3c), place preference learning (PPL) and reversal place preference learning (PPL-rev). A Time course of the daytime and nighttime activity represented as corner visits per hour (Visits/h) in 12-h intervals (12 h Bins). The fluctuations of activity reveal the circadian rhythms. Overall corner visiting activity was similar in both genotypes except few time points in PPL and PPLrev. Actograms (Additional file 1: Fig S2) support a moderately increased activity in PPL. *P < 0.05. B Time course of the ratio of Nosepokes per Visit (NP /Visit) in 12 h Bins. The ratio is an individual relative stable trait influenced by exploratory drive, motivation, compulsiveness, and attention. The NP /Visit ratio was higher in Avil-ChR2 mice. *P < 0.05. C During Free Adaptation (FA) Avil-ChR2 mice show longer licking duration in the night (please also see Additional file 1: Fig. S3 and Additional file 4: Tables of Multivariate Statistics) which agrees with compulsive licking. Licking in FA was ad libitum, not restricted by door opening times. Comparison by 2-way ANOVA “Day time” X “genotype” and posthoc Šidák for genotype. ***P < 0.001. D Time course of the proportion of correct corner visits in learning tasks with either three correct corners (NP 3-corner, NP3c) or one correct corner (PPL, PPL-reversal). In PPL reversal the correct corner was switched to the opposite side as compared to PPL. *P < 0.05. Line graphs of the time courses show the mean ± sem of n = 15 ChR2-flfl and n = 16 Avil-ChR2 female mice. Time courses were compared by 2-way ANOVA for repeated measurements with the within subject factor “time” and the between subject factor “genotype”, and subsequent posthoc comparison for each time point for genotype. Asterisks show *P < 0.05 (non-adjusted 2-group comparisons)