Figure 4.

In this set of experiments, male and female rats were exposed to different hormonal manipulations during very early development and tested as adults in their performance during trace conditioning and their response to stressful experience (Shors and Miesegeas 2002). (A) Females injected with one dose of vehicle on the day that they were born emitted many fewer learned responses after stress in adulthood. However, those injected with testosterone on the day that they were born emitted many more learned responses after stress in adulthood. (B) Males castrated on the day that they were born or exposed to a sham surgery emitted more learned response after stress in adulthood. (C) However, males in which testosterone receptors were antagonized in utero did not respond to acute stress in adulthood, whereas those exposed to a vehicle in utero emitted more learned responses after stress in adulthood. Overall, these data indicate that stress effects on learning are organized very early in development and are remarkably plastic.