Many women going through menopause start to see changes in their ability to remember things. Women can find this very worrying — such symptoms are not unlike early signs of dementia, or even Alzheimer’s Disease. However, age-related memory impairment is quite common and can be explained in part by hormonal changes, in particular loss of estrogen, and it involves a small part of the brain that resembles a seahorse.
The Hippocampus: Your Brain’s Memory Centre
The name “hippocampus” is actually the Latin word for seahorse. The hippocampus is located in the temporal lobe of the brain and is a component of the limbic system. Although referred to in the singular, we actually have two of them, arranged symmetrically one on each side of the brain. It plays an important role in the transfer of short-term memory to long-term memory and in the formation of new memories.
Anterograde amnesia — the loss of the ability to form new memories — is seen in people with damage to both hippocampi. The hippocampus is also important for spatial memory and navigation, like an inner GPS. Interestingly, it is also one of the first areas of the brain to show damage in Alzheimer’s disease.
The Hormonal Connection to Learning and Memory
As we age, fewer new neurons are formed in the brain, so our ability to learn and form memories results from the strengthening of connections between existing neurons rather than the formation of new ones. The modulation of neural connections is referred to as synaptic plasticity. Enhancement of synaptic plasticity that persists in response to a recent stimulus is called long-term potentiation (LTP) — the process by which memories are stored.
Local steroidogenesis of testosterone, dihydrotestosterone and estradiol (E2) from cholesterol occurs in hippocampal neurons, resulting in much greater levels of these hormones in the hippocampus than in the circulation. This local supply of androgens and estrogens is essential for influencing synaptic plasticity, through a number of mechanisms mostly involving E2 activity at estrogen receptors.
Age-related memory impairment is quite common and can be explained in part by hormonal changes, in particular loss of estrogen.
Estradiol increases synaptic plasticity both slowly, via classical nuclear estrogen receptors (ERα and ERβ), and rapidly, via ERα and ERβ located in the synapses. The local synthesis of E2 from androgens requires aromatase activity — patients undergoing treatment with aromatase inhibitors, such as postmenopausal women being treated for breast cancer, therefore have reduced E2 synthesis and subsequent decrease in hippocampal E2 levels.
To understand your current estradiol and hormone balance, our Comprehensive Female Saliva Hormone Profile (LCMS) measures the free, bioavailable fraction of estradiol, progesterone, testosterone and DHEA using gold-standard LCMS analysis — the most clinically relevant method for identifying the hormonal imbalances associated with menopause and cognitive change.
Estrogen Receptor Expression and Cognitive Function
The ability of E2 to exert beneficial effects on synaptic plasticity and cognitive function declines with advancing age because estrogen receptor expression decreases with age. Experiments in mice have suggested that supraphysiological E2 preferentially increases synaptic ERβ, which, along with the age-related decline in ERα, decreases the ratio of ERα/ERβ. This imbalanced ratio impairs transcriptional processes that preserve cognitive function, including those involved with neuroprotection and synaptic plasticity.
Don’t Close the Barn Door After the (Sea)horse Has Bolted
If estrogen replacement is started too late, this cannot restore hippocampal tissue that was already lost.
The age-related loss of hippocampal brain tissue is significantly greater in females than males, and this is related to low E2, since E2 acts as an antioxidant and protects the hippocampus from ischaemic stress damage. Estrogen replacement can protect against this loss early in menopause — however, if estrogen replacement is started too late, this cannot restore hippocampal tissue that was already lost.
In women aged 65 or older, higher endogenous, bioavailable (non-protein-bound) E2 levels have been found to be associated with a reduced likelihood of cognitive impairment. Transdermal E2 and progesterone given earlier in the postmenopausal period has been found to be beneficial in protecting against cognitive deterioration.
For women who want a comprehensive hormonal and wellness assessment with specialist interpretation, our Advanced Female Wellness Test (with Specialist Doctor Report) provides a broad picture of hormonal health alongside key wellness markers — with a full specialist doctor report to guide next steps.
Are Women at Greater Risk of Alzheimer’s Disease than Men?
The short answer is no. Although there is a higher prevalence of Alzheimer’s Disease (AD) in women compared to men, the explanation is that older age is the single greatest risk factor for AD and women tend to live longer than men. Women are simply more likely than men to reach an age where risk of developing AD is highest — however, they are not more likely than men to develop AD at any given age.
Menopause and the Brain: Where Are We Now?
It’s clear that hormones play an important role in brain function and neuroprotection. Hormone replacement started early in the menopause — known as the “window of opportunity” hypothesis — can make a difference in preserving functions like memory and preventing the onset and progression of neurodegenerative processes.
The neurobiological science underlying these processes is still in its infancy, and studies of how hormone replacement therapy and its timing affect the incidence and progression of neurodegenerative and psychiatric diseases are few. For women whose cognitive and mood symptoms may also involve neurotransmitter imbalances alongside hormonal changes, our Neurotransmitter & Saliva Hormone Test I measures GABA, serotonin, dopamine and other key neurotransmitters alongside saliva hormones — providing a comprehensive neurochemical and hormonal picture to guide targeted support.
Originally by Margaret Groves, ZRT Laboratory. Reproduced with permission. Last reviewed: May 2026.