Fig. 1.

Effects of heat stress on learning and memory in mice. (a) After mice (n = 12) were exposed to heat for 7, 14, or 42 days, we determined the percentage of spontaneous alternations and the number of arm entries in the Y-maze. (b) Cognitive function was also assessed using a passive avoidance task at different days after heat exposure. Columns represent the latency period for entering the dark box in the acquisition test and in the retention test, 24 h later. (c) Memory function after heat stress was determined by a novel object recognition test. Columns indicate the exploration time during the familiarization session and the percentage of time spent near the novel object among the total time spent exploring the objects during the test session. Values are expressed as means ± standard error of the mean (S.E.M.). *p < 0.05, **p < 0.01, and ***p < 0.001 as compared with the control group