Scans prove there’s no such thing as a ‘male’ or ‘female’ brain

You may have read that having a maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). brain will earn you more money. Or maybe that femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). brains are better at multitasking. But there is no such thing as a femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). or maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). brain, according to the first search for sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. differences across the entire human brain. It reveals that most people have a mix of maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). and femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). brain features. And it also supports the idea that gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
is non-binary, and that gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
classifications in many situations are meaningless.

“This evidence that human brains cannot be categorised into two distinct classes is new, convincing, and somehow radical”, says Anelis Kaiser at the University of Bern, Switzerland.

The idea that people have either a “female” or “male” brain is an old one, says Daphna Joel at Tel Aviv University in Israel. “The theory goes that once a fetus develops testicles, they secrete testosterone which masculinises the brain”, she says. “If that were true, there would be two types of brain”.

To test the theory, Joel and her colleagues looked for differences in brain scans taken from 1400 people aged between 13 and 85. The team looked for variations in the size of brain regions as well as the connections between them. In total, the group identified 29 brain regions that generally seem to be different sizes in self-identified males and females. These include the hippocampus, which is involved in memory, and the inferior frontal gyrus, which is thought to play a role in risk aversion.

“There are not two types of brain”

When the group looked at each individual brain scan, however, they found that very few people had all of the brain features they might be expected to have, based on their sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy.. Across the sample, between 0% and 8% of people had “all-male” or “all-female” brains, depending on the definition. “Most people are in the middle”, says Joel.

This means that, averaged across many people, sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. differences in brain structure do exist, but an individual brain is likely to be just that: individual, with a mix of features. “There are not two types of brain”, says Joel.

Spatial awareness

Although the team only looked at brain structure, and not function, their findings suggest that we all lie along a continuum of what are traditionally viewed as maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). and femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). characteristics. “The study is very helpful in providing biological support for something that we’ve known for some time – that gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
isn’t binary”, says Meg John Barker, a psychologist at the Open University in Milton Keynes, UK.

The findings will still come as a surprise to many, including scientists, says Bruce McEwen at the Rockefeller University in New York. “We are beginning to realise the complexity of what we have traditionally understood to be ‘male’ and ‘female’, and this study is the first step in that direction”, he says. “I think it will change peoples’ minds”.

Markus Hausmann at Durham University, UK, isn’t surprised by the findings, however. He has been studying sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. differences in cognition, such as whether men, as commonly believed, really do have better spatial awareness than women.

“Across all kinds of spatial skills, we find very, very few that are sensitive to sex”, says Hausmann. “We have also identified spatial problems where women outperform men – the black-and-white idea of a maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). or femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). brain is clearly too simple”.

Cultural expectations

Despite persisting stereotypes, girls are no worse than boys at science and maths subjects, either.

“People get wedded to the idea that being maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). or femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). is highly predictive of having different aptitudes or career choices”, says Margaret McCarthy, who studies brain sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. differences at the University of Maryland School of Medicine in Baltimore. “This study fights against the idea that these outcomes are based on biological differences, as opposed to cultural expectations”. Other body systems are also often wrongly considered to be either maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). or femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus)., says Joel.

Alexandra Kautzky-Willer, head of the Gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
Medicine Unit at the Medical University of Vienna in Austria, agrees that things aren’t so simple. “There are differences between men and women when you look in large groups, and these are important for diagnosis and treatment”, she says. “But there are always more differences within genders. We always need to look at culture, environment, education and a person’s role in society”, she says.

If a neuroscientist was given someone’s brain without their body or any additional information, they would still probably be able to guess if it had belonged to a manA human being who self-identifies as a man, based on elements of importance to the individual, such as gender roles, behaviour, expression, identity, and/or physiology. or a womanA human being who self-identifies as a woman, based on elements of importance to the individual, such as gender roles, behaviour, expression, identity, and/or physiology.. Men’s brains are larger, for example, and are likely to have a larger number of “male” features overall. But the new findings suggest that it is impossible to predict what mix of brain features a person is likely to have based on their sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. alone.

Genderless future

Joel envisions a future in which individuals are not so routinely classified based on gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
alone. “We separate girls and boys, men and women all the time”, she says. “It’s wrong, not just politically, but scientifically – everyone is different”.

But other scientists contacted by New Scientist don’t think that will ever be possible – as a sexually reproductive species, identifying a person’s biological sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. will always be of paramount importance to us, they say.

Even so, Joel’s findings can be used to help many people understand the non-binary nature of gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
, says Barker. After all, some people don’t identify as either maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). or femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus)., and others feel their gender identity• One’s innermost concept of self as male or female or both or neither – how individuals perceive themselves and what they call themselves. One’s gender identity can be the same or different than the sex assigned at birth. Individuals are conscious of this between the ages 18 months and 3 years. Most people develop a gender identity that matches their biological sex. For some, however, their gender identity is different from their biological or assigned sex. Some of these individuals choose to socially, hormonally and/or surgically change their sex to more fully match their gender identity.
• The gender to which one feels one belongs.
• Internal and psychological sense of oneself as a woman, a man, both, in between, or neither.
shift over time. “It’s a shame that people’s experience alone isn’t enough for us to recognise as a society that non-binary gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
is legitimate”.

“We need to start thinking a lot more carefully about how much weight we give to gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
as a defining feature of human beings, and stop asking for it in situations where it simply isn’t relevant”, says Barker.

Author – Jessica Hamzelou

Original posting date – 30 November 2015

Source – https://www.newscientist.com/article/dn28582-scans-prove-theres-no-such-thing-as-a-male-or-female-brain/