Effects of sex steroid hormones on memory

Many evidences have elucidated relevant mechanisms of action of estrogen, progesterone, and testosterone on cognition, including learning and memory processes, both in animal models and humans. This influence may depend on their modulator role on several neurotransmitter systems, and the extensive presence of their receptors in cerebral areas, involved in cognitive functions, including the amygdala, hippocampal formation, and cerebral cortex. The present brief review summarizes data of our research and others with the aim of clarifying, in mammals, the involvement of sex hormones on memory. In particular, after an introduction illustrating the general mechanisms of sex hormones modulation on memory processes, the specific role of estrogen, progesterone and testosterone in memory is described in three different sections. Besides summarizing the most relevant actions of sex steroid hormones in the modulation of learning and memory, in this review is also emphasized that many aspects and mechanisms are still not completely understood and extensive future research is necessary to elucidate them.