Do you feel a sense of clarity on some days? Everything you put your mind to, you ace it. But suddenly, the clarity is gone, there is a bit of brain fog. Turns out, it is because of your menstrual cycle.Even till this date, studies around woman's biology is lacking. However, some recent studies have shown that menstrual cycle causes brain to function a certain way. For instance, when a woman is ovulating, her sexual desires is at peak, whereas in the beginning of follicular phase a woman might experience clarity in imagination, perception, memory and social abilities. This is also the same time when spatial skills are better, and in the later follicular phase, the anxiety rises. Studies have also found that during the luteal phase, women feel calmer. The Hormone GameIn 2022, Pauline Maki along with colleagues from the Gerontology Research Centre studied the fluctuating oestrogen levels and its affects on woman's abilities over the course of each month. The study involved 16 women who were assessed twice. Once just after period when the oestrogen and progesterone levels were low and once more a week after they ovulated, when the hormone levels were high.The study found that when these hormones were at peak, the communication abilities in women increased, whereas right after period, the spatial abilities increased. The reason is in the Hausmann study, this reveals that a woman's tendency to use both sides of the brain becomes more extreme when the hormone levels increases each month. Studying The BrainA study led by neuroscientists Elizabeth Rizor and Viktoriya Babenko of the University of California Santa Barbara tracked 30 women throughout their menstrual cycles. Menstruators experience for about 450 periods during their lifetimes. The fluctuation of hormones during this time impacts behavioural, structural and functional abilities. To understand this better, the team took MRI scans of their subjects during the three menstrual phases: menses, ovulation and mid-luteal, which occurs after ovulation and lasts till before menstruation. The results showed that as hormones fluctuate, the gray and white matter in the scans change too. Oestrogen and the luteinizing hormones that spurs ovulation rise and shows a change in white matter in the scan, which suggests a better information transfer. While for progesterone that rises after ovulation, the tissue increases and cerebrospinal fluid volume decreases. What this means for the brain is yet unknown, but it opens door to more studies, including how menstrual cycle can impact mental health. Menstrual Cycle And MoodTurns out that mood swings are not just limited to menstruation or PMS, it changes throughout the menstrual cycle. A menstrual cycle consists of four different phases follicular phase, ovulation, luteal phase, and menses. Follicular PhaseThe follicular phase starts when you begin your menstrual cycle and lasts for about 14 to 21 days, this overlaps with your menses, which is when you are on your period. This means body secretes follicle-stimulating hormone, it does not have a say in your mood, and only helps eggs to grow. MenstruationWhile menses means that uterine blood and tissues comes out through vagina. Right before your period, you may feel blues or sick, an indication that your period is approaching. While on period the feelings of anxiety remains. OvulationOvulation is when the egg is matured and is released. This is when your oestrogen levels are at peak and it improves your mood, energy and also increases sex drives. LutealThe luteal phase is when the follicle left behind by the departing egg secretes progesterone, this increases cravings, lowers anxiety and improves sleep. However, when the egg is left unfertilised, the progesterone levels fall and leads to PMS.