Fig. 4

Retention of extinction memory in male mice. a The effect of various doses of testosterone. b The effect of various doses of 5α-DHT. Androgens (testosterone: 0.5 mg/tube; 5α-DHT: 0.05 mg/tube) significantly enhanced the retention of extinction memory in male mice. In contrast, the retention rate of extinction memory in the 2.0 T-dose group was the same degree as that of the 0 T-dose group. *p < 0.05