**5.2 Role of hippocampal neurogenesis in memory consolidation**

A previous study showed that exercise on a running wheel, which promotes neurogenesis, increased the rate of loss of hippocampus-dependent contextual fear memory (Kitamura et al., 2009). The study suggested that the level of hippocampal neurogenesis could be modulated and was associated with a causal relationship between adult neurogenesis and the hippocampus-dependent period of fear memory. It is theoretically possible, therefore, that promoting adult neurogenesis early in the transition period might facilitate the clearance of fear memory from the hippocampus. Modulating memory consolidation would mean that posttraumatic stress disorder could be prevented in the aftermath of a traumatic event.
