Structure, Behaviour And Disease
“New technologies have generated a growing pile of evidence that there are inherent differences in how men’s and women’s brains are wired and how they work. Not how well they work, mind you. Differences don’t mean one sex or the other is better or smarter or more deserving.”Larry Cahill, UC-Irvine professor of neurobiology and behavior
The brain is an incredible thing. Neuroscientists know so much and yet so little about this squishy mass entrapped within a human’s skull. And now more and more research time is being invested into finding out whether there are any differences between a male and female brain. With ethical issues such as neurosexism cropping up left, right and centre, it’s no wonder there are so few answers to tonnes of brain tingling questions.
For now, we’ll have to settle with the findings neuroscientists have spent a lifetime exploring and hope that the scientific studies used throughout this article will shine a light on the ins and outs of a woman’s brain.
A Woman’s Brain And Disease
Although worldwide, statistically women live longer than men, it’s surprising to uncover that illnesses which involve the brain are experienced more often by women. Zeenat F Zaid describes how these differences between a man’s and a woman’s brain “need to be considered in studying brain structure and function and may raise the possibility of sex-specific treatments for neurological diseases.” Especially when looking at diseases such as Alzheimer’s. If neurosexism fears stop further research, it may mean that a sex-specific remedy won’t be discovered any time soon.
Dr Victor W Henderson explored the role of estrogen and Alzheimer’s in women. He explains how “Alzheimer’s Disease affects women more often than men, and women with this form of dementia show greater naming (semantic memory) deficits during the course of their illness… Several estrogenic actions are potentially relevant to Alzheimer’s Disease and it is hypothesized that one consequence of estrogen deprivation after the menopause is a higher risk of this disorder.”
He goes onto explain that the role of estrogen in healthy women who don’t have dementia may be beneficial. In fact estrogen “may enhance cognitive performance, especially in the domain of verbal memory, although the magnitude of such effects is small. Several small treatment trials of estrogen replacement in women with Alzheimer’s disease, however, suggest that estrogen’s effects on cognition could be larger in this population and may be most apparent on tasks of semantic memory.”
He concludes that in these small studies an association between postmenopausal estrogen replacement therapy and a lower risk of “subsequent Alzheimer’s disease” can be made: “Postmenopausal estrogen replacement reduces a woman’s risk of subsequent dementia.”
Although, it’s worth bearing in mind that this study was done on a small scale and more research is needed.
A Woman’s Brain And Long-Lasting Structural Changes
“Neuroscience literature shows that the human brain is a sex-typed organ with distinct anatomical differences in neural structures and accompanying physiological differences in function.”Bruce Goldman, Stanford Medicine
When it comes to the brain and pregnancy, studies have shown that structural changes can take place during and after pregnancy. And those structural changes can often be long-lasting. Researcher Elseline Hoekzema says that “pregnancy involves radical hormone surges and biological adaptations”.
Hoekzema’s study involved the following control groups:
- First-time mothers and fathers.
- Nulliparous (women who have never given birth).
The study showed that “pregnancy renders substantial changes in brain structure, primarily reductions in grey matter (GM) volume in regions subserving social cognition.” They noted the changes were consistently seen in the mothers and not in nulliparous. “Furthermore, the GM volume changes of pregnancy predicted measures of postpartum maternal attachment, suggestive of an adaptive process serving the transition into motherhood.” A follow-up session 2 years later found that the GM reduction had maintained for a minimum of 2 years post-pregnancy.
The grey matter lost in this particular study was noted in the social cognition region. Psychologist and Professor Chris D Frith describes social cognition as “the various psychological processes that enable individuals to take advantage of being part of a social group.” If grey matter decreases in the social cognition region then it may mean a decrease in social cognition function. However, some decreases may make little difference. Either way, the brain’s ability to restructure in order to adapt to parenthood is incredible and a necessary part of human nature.
A Woman’s Brain And Behavioural differences
“The role of culture is not zero. The role of biology is not zero.”Dr David Halpern
Dr Bruce Goldman’s paper explores research and findings on cognitive differences between men and women. The research is taken from both old and new papers and combines small and large studies. As always, it’s worth bearing in mind that these studies may not have been duplicated or done in large quantities.
However, Goldman highlights many interesting and intriguing findings, some of which are summarised below:
- Female mice protect their nests from intruders due to “genes at work in their brain”.
- 34 rhesus monkeys were shown sex-specific toys. The females preferred plush-looking toys to toys with wheels. And vice versa for the male monkeys. Goldman says that “it would be tough to argue that the monkeys’ parents bought them sex-typed toys or that simian society encourages its male offspring to play more with trucks”.
- Women consistently “excel in several measures of verbal ability” and on average do far better on reading comprehension and writing ability measures than men.
- “Navigation studies in both humans and rats show that females of both species tend to rely on landmarks, while males more typically rely on “dead reckoning”: calculating one’s position by estimating the direction and distance traveled rather than using landmarks.”
- Women are twice as likely as men to “experience clinical depression in their lifetimes; likewise for post-traumatic stress disorder”.
- Women can retain more vivid and intense memories of emotional events than men.
- “The two hemispheres of a woman’s brain talk to each other more than a man’s do. In a 2014 study, University of Pennsylvania researchers imaged the brains of 428 male and 521 female youths — an uncharacteristically huge sample — and found that the females’ brains consistently showed more strongly coordinated activity between hemispheres, while the males’ brain activity was more tightly coordinated within local brain regions.”
With technologies advancing and neuroresearch on the rise, it can only mean that more and more findings about womens’ brains will be exposed and shared in the near future. However, with the issues that neruosexism can bring, scientists will need to be careful about how, what and why they do their research.
Hold that thought.
For now, keep your brain ticking with a selection of science-backed brain training games from Peak.
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