Natural sex hormone cycles and gender differences in memory.

OBJECTIVE To analyze gender differences in memory and the influence of the natural sex hormone cycles on it. METHOD A total of 20 men and 19 women were assessed with memory tests two times coinciding with two hormonal phases of the diurnal cycle of testosterone in men or menstrual cycle in women. RESULTS It was observed that women perform better than men in delayed verbal memory as well as in immediate and delayed object recall, and men in digit span. It was also found that there was a significant effect of the hormonal cycles on verbal working memory, immediate object recall and on the spatial component of visuoconstructive memory. Finally, hormonal cycles determine the existence and direction of gender differences in verbal working memory, delayed object recall and in the spatial component of visuoconstructive memory. CONCLUSIONS Natural sex hormone cycles seem to influence gender differences in some measurements of memory.