Yes - but not in the way the question usually implies.
The popular version of this story tends to go in one of two directions. Either hormones are irrelevant to cognition (a position that does not survive contact with the neuroscience), or they determine cognitive style in some fixed, binary way that maps neatly onto gender. Neither of these is accurate.
What the research actually shows is more interesting, and more practically useful, than either version.
What oestrogen does to attention
Oestrogen has receptors throughout the prefrontal cortex, the hippocampus, and the limbic system. It regulates serotonin and dopamine synthesis. It is, among other things, deeply involved in verbal fluency, working memory, fine-detail processing, and social cognition - the ability to read emotional states and relational nuance accurately.
This matters across the menstrual cycle in measurable ways. During the high-oestrogen follicular phase, verbal tasks, fine motor skills, and social processing tend to be more fluid. The brain is, in a sense, well-supplied with the neurochemical infrastructure those tasks require.
What this produces is an attentional style that is contextually sensitive - good at tracking multiple cues simultaneously, responsive to interpersonal information, better at the kind of distributed attention that complex social and professional environments demand.
What testosterone does to attention
Testosterone is associated with a different attentional profile. Research links higher testosterone to stronger visuospatial processing, greater capacity for single-task sustained focus, reduced social monitoring (less attentional allocation to interpersonal cues), and somewhat higher risk tolerance in decision-making.
This is a more narrowly focused attentional style - better suited to deep single-task engagement than to the rapid context-switching that oestrogen-supported cognition handles well.
Neither of these profiles is superior. They are differently suited to different tasks. Context determines which is the more useful resource in any given moment.
There is no cognitively superior hormone. There are different attentional styles - and most people, across a lifetime, will need both.
Where perimenopause comes in
The perimenopausal transition does not involve a clean, gradual decline in oestrogen. It involves significant, often unpredictable fluctuation - spikes and drops that can occur within the same week. The brain's attentional and cognitive systems are calibrated to work within a relatively stable hormonal environment. When that environment becomes volatile, performance becomes volatile.
This is why the perimenopausal cognitive experience tends to be described not as steady decline but as inconsistency. Sharp days and foggy days. Weeks of mental clarity followed by periods when words disappear and concentration fragments. The brain is not malfunctioning. It is working within parameters that keep changing.
There is also a testosterone picture worth noting. Women experience a gradual decline in testosterone across midlife, which can contribute to reduced drive, flatter affect, and decreased capacity for the sustained single-focus engagement testosterone supports. Some women describe, counterintuitively, gaining a different kind of clarity in this phase - less interest in social monitoring, more interest in direct engagement with ideas or problems. That shift is not pathological.
What is actually useful to know
The clinically significant issue is not the neuroscience itself - it is what women do with the absence of it. When cognitive changes arrive without explanation, the gaps get filled with the worst available interpretation: early dementia, permanent decline, something fundamentally wrong. That interpretation generates anxiety, which impairs exactly the prefrontal function in question. The cognitive difficulty and the fear of it become mutually reinforcing.
Knowing what is actually happening does not eliminate the difficulty. But it changes the relationship to it entirely. A woman who understands that her working memory is affected by oestrogen instability - not by some irreversible deterioration - is in a completely different position to adapt, seek support, and treat herself with the quality of care the situation actually warrants.
The brain at midlife is not failing. It is adapting to a new hormonal context with inadequate information and, usually, inadequate support. Providing the information is the least we can do.