Fig. 2

Barnes maze task performance. a From D14 to D18 post-TBI, acquisition learning trials were performed, and the time it took to locate and enter into the escape box was reported. The average performance of three trials per day was expressed as mean ± SE. A shorter duration indicates faster spatial learning. b The exploration paths of D14 and D18 (the first and last acquisition days, respectively) were analysed and classified into six strategies. The best strategy (direct) was given a score of 1 and the worst (random) a score of 0. The performance during the three trials on each day was plotted as separate data points. A higher score indicates a better exploration strategy. c The frequency of employing each strategy was plotted. d An example of each exploration strategy is provided. e Probe trials were performed on D19, 2 M, 6 M, and 8 M post-TBI, during which the escape box was removed. The time spent inside the north quadrant (the previous escape box location) is plotted. The dotted line represents the expected amount of time that would have been spent by random. A longer time duration indicates better spatial memory. f The time spent around the previous escape box location is plotted. The dotted line represents the expected amount of time spent by randomly exploring each possible box location. A longer duration indicates better and more precise spatial memory. g Reverse trials were performed on D20, 2 M, 6 M, and 8 M post-TBI, in which the escape box was placed at the opposite location. A shorter duration indicates better spatial unlearning and relearning. Data are expressed as mean ± S.E. Statistical results are provided below each panel. Blue and red asterisks represent significant post hoc differences between WT-Sham and WT-TBI and between APP/PS1-Sham and APP/PS1-TBI, respectively (* p < 0.05). n = 10–13 per genotype per injury per time point