Certain regions of the women’s brain involved in memory and learning are impacted by hormones during the menstrual cycle.
- Estradiol and progesterone are two sex hormones.
- The fluctuation in their quantity during the menstrual cycle impacts women’s brains.
- The regions of the brain most impacted are linked to memory.
Except in certain cases, a woman’s menstrual cycle lasts on average 28 days and repeats every month. Throughout this, sexual hormones evolve. Researchers from the Max Planck Institutein Germany, wanted to understand their impact on the brain.
Sex hormones impact the brain
According to their results, published in the journal Nature Mental Health, Brain regions involved in memory are believed to be remodeled during the menstrual cycle due to these hormone fluctuations.
Of previous work had already shown a link between menopause and cognitive decline. But, in this new study, scientists studied the consequences on the brain during women’s reproductive years.
To do this, they analyzed blood samples from 27 participants at six times during their menstrual cycle. In parallel, they studied two areas of the brain, the medial temporal lobe and the hippocampus, which have a significant quantity of sex hormone receptors and which have an essential role in memorization.
When it comes to sex hormones, scientists analyzed estradiol and progesterone. The first increases during the first half of the cycle until ovulation. Progesterone, for its part, is more present during the second half of the cycle and, in addition to its role in the reproductive system, this hormone has anxiolytic effects.
Two hormones of the menstrual cycle impact the brain
“Certain regions of the medial temporal lobe, essential for episodic memory and spatial cognition, develop when estradiol levels are high and progesterone levels are low, that is, these brain areas remodel according to the cycle menstrual, noted Julia Sacherone of the researchers, in a communicated. We now wish to understand whether these [adaptations en fonction du cycle] are modified in people at risk for memory and affective disorders in several follow-up studies.“
Scientists believe that there is not enough research conducted on the brains of women of reproductive age. “Even though steroid sex hormones [l’un des types d’hormones sexuelles] strongly impact learning and memory, less than 0.5% of the neuroimaging literature studies hormonal transition phases, such as the menstrual cycle, the influence of hormonal contraceptives, pregnancy and menopause, concludes Julia Sacher. To identify mechanisms linked to the risk and persistence of mental health disorders, such as depression or Alzheimer’s disease, we need a deeper understanding of how the healthy female brain adapts to change.“
