Men’s And Women’s Brains Found To Be Different Sizes
Men really do have bigger brains, reports the Daily Mail, going on to report that new research reveals male and female brains are wired differently with particularly big differences in the areas that control language and emotion.
It is well established that males and females have different predispositions towards developing different mental health conditions. For example, conditions such as autism spectrum disorder and dyslexia are more common in men, while depression and anxiety are more common in women. New research has pooled the results of 126 studies examining the differences in brain size between men and women to see if structural differences are part of the explanation.
It found that on average men had larger overall brain volumes than women. They also found differences between men and women in the volume of many different regions. These included regions previously associated with different mental health conditions. For example, men tended to have larger volumes in brain regions associated with survival instincts, memory and learning, while women tended to have larger volumes in areas of the brain dealing with language and emotions.
You could make a case that this differing mix of abilities means that it is mutually advantageous for the sexes to co-operate a nice thought for Valentines Day.
Gender is influenced by both biological and social factors and its not yet clear how these interact to influence behaviour, personality or disease risk.
Regional Gray Matter Volumes
As illustrated in Figure 1a, for the comparisons of regional GM volumes between all men and all women, we revealed significant main effects of sex at p = 0.05 and restricting outcomes to clusters exceeding k = 1000 voxels . There were no significant effects of brain size and no significant interactions between sex and brain size.
Sex differences in regional GM . Displayed are maximum intensity projections superimposed onto the SPM standard glass brain template . a illustrates the main effect of sex . Statistical outcomes are corrected for multiple comparisons using FDR at p = 0.05. Shown are clusters exceeding a spatial extent threshold of 1000 voxels, which corresponds to the expected numbers of voxels per cluster. be illustrate the outcomes of the subsequent post hoc tests, where women have larger regional GM volumes than men . The illustrated spatial profiles are significant at p = 0.001 without applying cluster extent thresholds.
Figure 2 provides the detailed T statistics associated with the specific comparison within the matched sample at p = 0.05 and k = 1000. As illustrated, we revealed significantly larger GM volumes in women than in men in the following three main clusters: cluster 1 consisted of the left and right caudate . Cluster 2 comprised regions of the left superior temporal gyrus, and cluster 3 encompassed regions of the left superior frontal gyrus .
Mri Data Acquisition And Preprocessing
The database used in this work is from the Human Connectome Project . This open-access database contains data from 1,065 subjects, including 490 men and 575 women. The ages range is from 22 to 36. This database represents a relatively large sample size compared to most neuroimaging studies. Using this open-access dataset allows replication and extension of this work by other researchers.
We performed DTI data preprocessing includes format conversion, b0 image extraction, brain extraction, eddy current correction, and tensor FA calculation. The first four steps were processed with the HCP diffusion pipeline, including diffusion weighting , direction , time series, brain mask, a file for gradient non-linearities during model fitting, and log files of EDDY processing. In the final step we use dtifit to calculate the tensors to get the FA, as well as mean diffusivity , axial diffusivity , and radial diffusivity values.
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What Did The Research Involve
The researchers looked for studies published between 1990 and 2013. They included those that provided information on the overall brain volumes for male and females, and the volumes of specific regions of the brain, for example:
- grey matter
- white matter
- cerebrospinal fluid surrounding the brain and spinal cord
The researchers used statistical methods to combine the results of the studies, taking into account differences between the studies and their results, and potential biases .
The researchers identified 126 studies which provided data on the volume of the brain and how it differed by gender. Fifteen of these studies provided results for total brain volume that could be combined in meta-analysis, and nine studies provided information on brain tissue density that could be combined.
Allen Institute Investigates The Complexities Of The Brain
According to the tests, women score better in memory tests than their male counterparts – despite their brains being 14 per cent smaller on average.
But the latest research from the Netherlands also found women are less intelligent than men by 3.75 IQ points on average and do significantly worse in tests of spatial ability.
Lead author Dr Dimitri van der Linden said: We found that mens brains are larger than womens and our analysis suggests this is the reason for lower average general intelligence across a range of tests.”
We found that mens brains are larger than womens and our analysis suggests this is the reason for lower average general intelligence
Lead author Dr Dimitri van der Linde
He added: We are aware of previous research suggesting womens brains are better organised or process information more efficiently but we did not look at this in our study.
He added that the size of the male brain is the reason for their higher IQs, although he also admitted that “female brains are better organised and process information more efficiently”.
Brain size in the sexes is a hotly debated topic in the scientific community.
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Massive Study Reveals Few Differences Between Men And Women’s Brains
How different are men and women’s brains? The question has been explored for decades, but a new study led by Rosalind Franklin University neuroscientist Lise Eliot is the first to coalesce this wide-ranging research into a single mega-synthesis. And the answer is: hardly at all.
“Men and women’s brains do differ slightly, but the key finding is that these distinctions are due to brain size, not sex or gender,” Dr. Eliot said. “Sex differences in the brain are tiny and inconsistent, once individuals’ head size is accounted for.”
The unusually large study of studies, “Dump the ‘dimorphism’: Comprehensive synthesis of human brain studies reveals few male-female differences beyond size,” published in Neuroscience and Biobehavioral Reviews, finds that size is the only clear-cut difference between male and female brains. Women’s brains are about 11% smaller than men’s, in proportion to their body size. Smaller brains allow certain features, such as a slightly higher ratio of gray matter to white matter, and a higher ratio of connections between, versus within, cerebral hemispheres.
“This means that the brain differences between large- and small-headed men are as great as the brain differences between the average man and woman,” Dr. Eliot said. “And importantly, none of these size-related differences can account for familiar behavioral differences between men and women, such as empathy or spatial skills.”
Why Are People’s Brains Different Sizes
There are many tactics people use to end arguments and confrontations, most of them having to do with size. Parents, for example, seem to favor “Because I said so” as a way to put a stop to a disagreement with their children, who, after all, are much smaller than they are for at least a little while. School bullies have the reputation of being big kids, their stature all the more advantageous for stuffing the wimpy geeks down the toilet. And let’s say that a couple is arguing about the best way to get to their destination conceivably, the man could end the argument by saying, “Of course, I’m right! Males have bigger brains.”
Men do in fact have bigger brains than women. The average human brain weighs in at 2.7 pounds, or 1,200 grams, which is about 2 percent of our body weight . Males, though, have about a 100 g advantage after accounting for differences in total body weight .
Which brings us to the age-old question: Does size really matter? That is, does the male in this scenario have any sort of valid point when he claims to be smarter with his bigger brain? On first glance, one might think so, because the way that we humans differentiate ourselves from our earlier primate ancestors is by our bigger brains. But if bigger is better, does that mean we are only slightly smarter than a walrus, which has a brain weighing 2.4 pounds , and much dumber than a sperm whale, which has a whopping 17-pound brain ?
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There Are Positive Cognitive Changes About The Time Of Ovulation Yet I Haven’t Come Across An Ovulation Euphoria Questionnaire Gina Rippon
The perceptions of PMS also betray a certain confirmation bias among researchers studying sex and gender differences, who have tended to conduct studies that back up the stereotypes rather than looking for the evidence that may question prevailing assumptions. Rippon says that women may actually experience a cognitive boost at certain points in the menstrual cycle, for instance but these have been largely ignored, thanks to scientists preoccupation with womens perceived weakness.
We’ve done some studies showing that cognitively, there are fluctuations through the menstrual cycle, she says. Verbal and spatial working memory, for instance, improve when oestrogen is highest. And that there are very positive changes about the time of ovulation improved responsiveness to sensory information, for example, and improved reaction time.
Spatial Location Of Sex Effects
While we did not detect any regions of larger GM volume in men than in women, there were a number of regions indicating larger GM volumes in women than in men. We will comment on significance clusters detected when comparing matched women and matched men in particular. This constitutes the special case of this study, where possible effects of brain size can be excluded with certainty. As detailed below, there is a strong resemblance between current findings and outcomes from previous studies . Of note, brain size matching is not proposed to substitute traditional analyses that include men and women with different brain sizes. Such analyses will continue to provide important clues about differences between male and female brains, especially if appropriate strategies are used to account for individual differences in brain size. However, brain size matching, as applied in the present study, clarifies whether observed sex differences are attributable to brain size or to biological sex per se.
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Facts About A Woman’s Brain
“There is no such thing as a unisex brain,” says neuropsychiatrist Dr. Louann Brizendine of the University of California in San Francisco and author of “The Female Brain.”
Despite the trumpets of women’s lib, science suggests sex differences are innate. Women, apparently, are not curvy versions of men sporting high-heeled shoes.
Here are 10 things every woman-loving man should know.
She Really Is Intuitive
Men can have the uncomfortable feeling that women are mind readers or psychics, Brizendine said. But women’s intuition is likely more biological than mystical.
Over the course of evolution, women may have been selected for their ability to keep young preverbal humans alive, which involves deducing what an infant or child needs warmth, food, discipline & mdash without it being directly communicated. This is one explanation for why women consistently score higher than men on tests that require reading nonverbal cues. Women not only better remember the physical appearances of others but also more correctly identify the unspoken messages conveyed in facial expressions, postures and tones of voice, studies show.
This skill, however, is not limited to childrearing. Women often use it tell what bosses, husbands and even strangers are thinking and planning.
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What Kind Of Research Was This
This was a systematic review that searched the global literature aiming to identify published studies that used imaging to examine the brain structure of men and women. The researchers then aimed to combine the findings and summarise any gender differences found.
The rates of many different mental health and neurological conditions are known to differ between men and women, as are their symptoms and age of onset. For example male-biased conditions include attention deficit hyperactivity disorder and autism, while female-biased conditions include depression and anxiety.
As the researchers say, understanding the different effects gender has on brain development may increase understanding of how and why male and female brains differ in their predisposition for, or resilience against, certain mental conditions.
Though several previous studies have examined gender differences in brain structures, the researchers say that theirs is one of the first to have compared the results of these various studies in meta-analysis. They first aimed to look at overall brain volume , then to look at differences in specific regions of the brain.
How Our Brains Differ
The 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, says UC-Irvine professor of neurobiology and behavior Larry Cahill, PhD. Cahill edited the 70-article January/February 2017 issue of the Journal of Neuroscience Research the first-ever issue of any neuroscience journal devoted entirely to the influence of sex differences on nervous-system function.
Brain-imaging studies indicate that these differences extend well beyond the strictly reproductive domain, Cahill says. Adjusted for total brain size , a womans hippocampus, critical to learning and memorization, is larger than a mans and works differently. Conversely, a mans amygdala, associated with the experiencing of emotions and the recollection of such experiences, is bigger than a womans. It, too, works differently, as Cahills research has demonstrated.
Discoveries like this one should ring researchers alarm buzzers. Women, its known, retain stronger, more vivid memories of emotional events than men do. They recall emotional memories more quickly, and the ones they recall are richer and more intense. If, as is likely, the amygdala figures into depression or anxiety, any failure to separately analyze mens and womens brains to understand their different susceptibilities to either syndrome would be as self-defeating as not knowing left from right.
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Male And Female Brains Really Are Built Differently
The hemispheres of women’s brains are more interconnected. Does that matter?
Ready your knowing smirk, because here comes a scientific gem thats sure to enliven even the dullest of holiday parties.
By analyzing the MRIs of 949 people aged 8 to 22, scientists at the University of Pennsylvania found that male brains have more connections within each hemisphere, while female brains are more interconnected between hemispheres.
Yes, take that, Mike from IT! It, like, so explains why you just dropped the eggnog while attempting to make flirty conversation with Janet from Accounting.
Just kidding we still have no idea why men or women do anything in particular. But the study, released today in the Proceedings of the National Academy of Sciences, is interesting because it is one of the first to discover differences in the brains structural connectivity in a large sample size of people from a variety of age groups.
Because female brains seem to have a stronger connections between their logical and intuitive parts, when women are asked to do particularly hard tasks, they might engage very different parts of the brain, said Ragini Verma, an associate professor of radiology at the University of Pennsylvania and one of the authors of the report. Men might over-engage just one part of the brain.
The differences were less evident in young children, but they became prominent in the scans of the adolescents.
Spoken like someone who has her intuition wired firmly to her logic.
Study: Womens Brains Are Smallerbut More Efficient
A new study finds that men and women have equivalent brainpower because women use their brainswhich tend to be smaller in size than mens brainsmore efficiently.
Previous research has suggested a difference in size between male and female brains. For the study, which was published in the journal Intelligence, University of California researchers studied several male and female hippocampuses, the area of the brain that houses emotion and memory function.
Researchers found that a mans larger hippocampus increased the presence of neurons, indicating higher intelligence. However, a woman’s smaller hippocampus uses less energy and fewer brain cells to achieve the same results, indicating equivalent brainpower to that produced by larger male brains.
“At this structural level, females might show greater efficiency requiring less neural material for achieving behavioral results on par with males,” the study says .
Current ArticleStudy: Womens brains are smallerbut more efficient
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Comparisons With Tract Based Spatial Statistics And Support Vector Machine
To justify the effectiveness of our method, the Tract Based Spatial Statistics and Support Vector Machine were applied to our dataset as comparisons, since these are two popular methods for data analysis in neuroimaging studies . We compared the results in following two conditions: We used the SVM as the classifier while keeping the same preprocessing procedure in order to compare its results with our 3D PCNN method. We flatten each sample from the 3D FA matrix into a vector, and then fed the SVM with the vector. We used the TBSS to identify the brain regions where are shown the statistically significant gender-related difference.
Where Did The Story Come From
The study was carried out by researchers from University of Cambridge and University of Oxford and was funded by the Wellcome Trust and Medical Research Council Behavioural and Clinical Neuroscience Institute.
The UK medias reporting is arguably over-speculative. The research was looking at structural differences only it didnt explore how these differences impacted disease, behaviour or intelligence, although it put forward plausible theories. And the Daily Stars claim that It has been revealed that male and female brains are completely different is simply incorrect.
It is also probably simplistic to assume that there is a direct link between brain size and intelligence. It is thought that it is the complexity of the connections between individual brain cells that underpin cognitive ability and not the total amount of brain tissue.
For example, elephants have huge brains, weighing around five kilos. And while elephants are certainly bright creatures, renowned for their memory, it would be a bit of stretch to describe them as geniuses.
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