Study reveals striking differences in brain connectivity between men and women

Brains networks show increased connectivity from front to back and within one hemisphere in males (upper) and left to right in females (lower). Credit: Ragini Verma, Ph.D., Proceedings of National Academy of Sciences

A new brain connectivity study from Penn Medicine published today in the Proceedings of National Academy of Sciences found striking differences in the neural wiring of men and women that's lending credence to some commonly-held beliefs about their behavior.

In one of the largest studies looking at the "connectomes" of the sexes, Ragini Verma, PhD, an associate professor in the department of Radiology at the Perelman School of Medicine at the University of Pennsylvania, and colleagues found greater neural connectivity from front to back and within one hemisphere in males, suggesting their brains are structured to facilitate connectivity between perception and coordinated action. In contrast, in females, the wiring goes between the left and right hemispheres, suggesting that they facilitate communication between the analytical and intuition.

"These maps show us a stark difference—and complementarity—in the architecture of the human that helps provide a potential neural basis as to why men excel at certain tasks, and women at others," said Verma.

For instance, on average, men are more likely better at learning and performing a single task at hand, like cycling or navigating directions, whereas women have superior memory and social cognition skills, making them more equipped for multitasking and creating solutions that work for a group. They have a mentalistic approach, so to speak.

Past studies have shown sex differences in the brain, but the neural wiring connecting regions across the whole brain that have been tied to such cognitive skills has never been fully shown in a large population.

In the study, Verma and colleagues, including co-authors Ruben C. Gur, PhD, a professor of psychology in the department of Psychiatry, and Raquel E. Gur, MD, PhD, professor of Psychiatry, Neurology and Radiology, investigated the gender-specific differences in brain connectivity during the course of development in 949 individuals (521 females and 428 males) aged 8 to 22 years using (DTI). DTI is water-based imaging technique that can trace and highlight the fiber pathways connecting the different regions of the brain, laying the foundation for a structural connectome or network of the whole brain.

This sample of youths was studied as part of the Philadelphia Neurodevelopmental Cohort, a National Institute of Mental Health-funded collaboration between the University of Pennsylvania Brain Behavior Laboratory and the Center for Applied Genomics at the Children's Hospital of Philadelphia.

The brain is a roadmap of neural pathways linking many networks that help us process information and react accordingly, with behavior controlled by several of these sub-networks working in conjunction.

In the study, the researchers found that females displayed greater connectivity in the supratentorial region, which contains the cerebrum, the largest part of the brain, between the left and right hemispheres. Males, on the other hand, displayed greater connectivity within each hemisphere.

By contrast, the opposite prevailed in the cerebellum, the part of the brain that plays a major role in motor control, where males displayed greater inter-hemispheric connectivity and females displayed greater intra-hemispheric connectivity.

These connections likely give men an efficient system for coordinated action, where the cerebellum, which involves perception, and the front of the brain, which involves action, are bridged together, according to the authors. The female connections likely facilitate integration of the analytic and sequential processing modes of the left hemisphere with the spatial, intuitive information processing modes of the right side.

The authors observed only a few gender differences in the connectivity in children younger than 13 years, but the differences were more pronounced in adolescents aged 14 to 17 years and young adults older than 17.

The findings were also consistent with a Penn behavior study, of which this imaging study was a subset of, that demonstrated pronounced sexual differences. Females outperformed males on attention, word and face memory, and tests. Males performed better on spatial processing and sensorimotor speed. Those differences were most pronounced in the 12 to 14 age range.

"It's quite striking how complementary the brains of women and men really are," said Dr. Ruben Gur. "Detailed connectome maps of the brain will not only help us better understand the differences between how men and women think, but it will also give us more insight into the roots of neurological disorders, which are often sex related."

Next steps are to quantify how an individual's neural connections are different from the population; identify which neural connections are gender specific and common in both; and to see if findings from functional magnetic resonance imaging (fMRI) studies fall in line with the connectome data.

More information: "Sex differences in the structural connectome of the human brain," by Madhura Ingalhalikar et al. www.pnas.org/cgi/doi/10.1073/pnas.1316909110

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____________
Dec 02, 2013
This comment has been removed by a moderator.
goracle
1.5 / 5 (8) Dec 02, 2013
Chicks chat; dudes do.

It's clear what underscores don't do: actual science.
Egleton
1.3 / 5 (12) Dec 02, 2013
Males on this site show low social skills and complete hemispheric isolation. Whats in the Left Brain stays in the left brain.
Hence the paramount importance of "The Model" that has to be defended with grunts and howls.
Shabs42
1 / 5 (1) Dec 03, 2013
Interesting study and does back up intuition. One implication that I doubt we'll ever see is that women would likely make better generals and coaches, even if men are generally the stronger and faster; and therefore, better soldiers (in classic combat at least) and athletes.
Sinister1811
4.5 / 5 (2) Dec 03, 2013
Chicks chat

Yes, way much more than necessary.

dudes do.

Only when they feel like it.
Fabio P_
not rated yet Dec 03, 2013
Males on this site show low social skills and complete hemispheric isolation. Whats in the Left Brain stays in the left brain.


The lateralisation of brain function is vastly more complicated than that.
shavera
5 / 5 (2) Dec 03, 2013
Does the study address nature v. nurture questions? Is the connectome found a function of absolute gender differences, or is it a question of how one is raised (boys perhaps being encouraged to be more physical, girls being encouraged to be more social) that is driving the brain to reinforce pathways that are called on more often?
210
1.2 / 5 (5) Dec 03, 2013
Interesting study and does back up intuition. One implication that I doubt we'll ever see is that women would likely make better generals and coaches, even if men are generally the stronger and faster; and therefore, better soldiers (in classic combat at least) and athletes.

No, what you should more likely and empirically find is that there will exist degrees of variation between these two male/female models. Men, with their better spatial orientation and abstract reasoning skills backed by a greater intuitive insight marshaling data from the opposing hemisphere, for example. The only limit women have are the needs placed in/on them requiring that more of their resources, all resources, be dedicated to child nurturing and care and, at times, nearly 60 per cent of what they eat going to a new life form. But, men have always shown a more robust abstract concept mastery and spatial orientation skill critical to field and force management.
word-
Moebius
1 / 5 (2) Dec 07, 2013
I could have predicted that the connectivity differences aren't there in kids. It's because we wire our brains as we get older with our choices, not vice versa. If you find a woman, say an engineer, you will find that she made different choices as a child and her brain will be wired more like a male engineer than a typical woman. Stupidity and ignorance is a choice not a birth defect.
Egleton
1 / 5 (1) Dec 07, 2013
Males on this site show low social skills and complete hemispheric isolation. Whats in the Left Brain stays in the left brain.


The lateralisation of brain function is vastly more complicated than that.

That is not what the study shows.The corpus callosum's function is to isolate the functions of the left and right hemispheres. The model making Left hemisphere is oblivious to the existence of the gestalt right.
This is why males fight so much to protect their models, because males have greater hemispheric isolation and the speech centers are mediated by the Left.
This is consistent with the findings above.
Question. Why has evolution produced two brains when one would be more pragmatic and why such a small (and shrinking) callosum connecting them?
goracle
not rated yet Dec 08, 2013
Chicks chat; dudes do.

It's clear what underscores don't do: actual science.

By way of explanation, the user ________ seems to have been NikfromNYC under a different name after the former account was banned. I am referring to a post that has been removed.