Your ovaries and uterus aren’t the only organs in transition during menopause. Because of declining oestrogen levels, your brain also experiences chemical changes that can alter the way you think and feel.
Early evidence suggests that decreased oestrogen levels may alter how the brain encodes and retrieves data. Researchers using magnetic resonance imaging (MRI) have discovered, for instance, that menopausal women who don’t take oestrogen may experience less activation of the left brain during the encoding of information. Perhaps that’s why some women reportedly have trouble with rational or analytical ‘left-brained’ thought processes such as those involved in balancing a chequebook or making decisions. Marian Van Eyk McCain, in Transformation Through Menopause, calls this effect ‘cottonhead’. If indeed it exists, it seems to be temporary. And studies show that oestrogen replacement may reverse it.
Scientists are only beginning to understand the complex effects of oestrogen on the brain. In animals, the hormone has been shown to stimulate the growth of dendrites, hairlike projections that facilitate communication between neurones (brain cells). It also seems to boost levels of the neurotransmitter acetylcholine. And it appears to help protect neurones in certain areas of the brain — especially the hippocampus, a region critical to learning and memory — from damage that leads to cell death. The chance that oestrogen may delay or possibly even prevent the onset of Alzheimer’s disease is currently being investigated. So far, studies have only yielded mixed results.
The memory connection
Can’t remember where you left the car keys or why you just walked into the kitchen? Some women notice some temporary lapses in short-term memory as they approach menopause, and their shifting oestrogen levels may be partly to blame.
Researchers have discovered that areas of the brain involved in memory are oestrogen-sensitive. And women taking oestrogen show more activity in brain areas associated with memory. Some studies have shown that women taking oestrogen performed better on memory tests than those not taking the hormone. But other studies have failed to confirm these results. Regardless, the majority of women may not experience any memory problems as they go through menopause.
Menopause and mood
What about mood swings? Some women experience them, probably the result of fluctuating hormone levels. But, contrary to popular belief, women do not suffer an increased risk of depression during this period. In fact, research shows that menopausal women actually have a lower incidence of depression than younger women.