[Home]   [Full version]  

When It Comes to Brains, Size Matters

Jun 20 ,General Science


Findings of a three-year study by researchers at the University of California, Riverside and the University of Florida, Gainesville run counter to the popular belief that women have better language skills than men.

In a study of 200 university students, the researchers found that women and men performed similarly on tests of language and reading skills. Differences in brain organization between men and women may be driven by sex differences in brain size, they said.

“People have said women have relatively larger language areas of the brain,” said Christine Chiarello, UCR professor of psychology. “In none of our language tasks were women better than men. When you account for differences in brain size between men and women there are few differences in the relative size of areas. While there are differences between men and women, those differences are minimal compared to the wide range of individual differences in both sexes.”

The study, “Size Matters: Cerebral Volume Influences Sex Differences in Neuroanatomy,” was published recently in the journal Cerebral Cortex.

The researchers gathered demographic data, tested language and reading skills, and performed magnetic resonance imaging to map brain structures of 100 female students and 100 male students. The men and women were similar in age, parental education and proportion of students who were right- or left-handed.

There were great individual differences in brain organization, brain size and where language and speech are processed, Chiarello said. For most people, speech and language are processed in the left half of the brain.

Differences in brain size account for much of the variance in brain structure size that at first glance might appear to be attributable to sex, Chiarello said. On average, the brains of men in the study were 13 percent larger than the women.

Men and women “confront similar cognitive challenges using differently sized neural machinery,” the researchers wrote. Their findings imply that “any sex-specific adaptations to overall brain size are not associated with large relative differences in the size of various cerebral regions. In this respect, our results suggest that brain size matters more than sex.”

Study co-authors include Chiarello; Christiana M. Leonard and Stephen Towler of the Evelyn F. and William L. McKnight Brain Institute of the University of Florida; UCR graduate students Suzanne Welcome and Laura K. Halderman; Ron Otto of the Computerized Diagnostic Imaging Center, Riverside; and Mark A. Eckert of the Medical University of North Carolina.

Source: University of Florida

Related stories:

3D Virtual Reality Environment Developed at UC San Diego Helps Scientists Innovate
Its name sounds like something out of science fiction, but the StarCAVE at the University of California, San Diego is now a science fact. The virtual-reality environment allows groups of scientists to venture into worlds as small as nanoparticles and as big as the cosmos – permitting new insights that could fuel discoveries in many fields. Early users of the StarCAVE include UC San Diego researchers in biomedicine, neuroscience, structural engineering, archaeology, earth science, genomics, art history and other disciplines.
Gene enhancer in evolution of human opposable thumb
Scientists have discovered a gene enhancer, known as HACNS1, that may have contributed to the evolution of the uniquely opposable human thumb, and possibly also modifications in the ankle or foot that allow humans to walk on two legs, according to a paper published in Science on Sept. 5, 2008.
Researchers Study Facial Structures, Brain Abnormalities to Reveal Formula for Earlier Detection of Autism
(PhysOrg.com) -- Recently, Harvard researchers reported that children with autism have a wide range of genetic defects, making it nearly impossible to develop a simple genetic test to identify the disorder.
Human brains pay a price for being big
Metabolic changes responsible for the evolution of our unique cognitive abilities indicate that the brain may have been pushed to the limit of its capabilities. Research published today in BioMed Central's open access journal Genome Biology adds weight to the theory that schizophrenia is a costly by-product of human brain evolution.
Do birds have a good sense of smell?
The sense of smell might indeed be as important to birds as it is to fish or even mammals. This is the main conclusion of a study by Silke Steiger (Max Planck Institute for Ornithology) and her colleagues. The sense of smell in birds was, until quite recently, thought to be poorly developed. Recent behavioural studies have shown that some bird species use their sense of smell to navigate, forage or even to distinguish individuals.
What It's Like to Be a Bat
Not many people think about what it's like to be a bat, but for those who do, it's enlightening and potentially groundbreaking for understanding aspects of the human brain and nervous system.
Researchers find an evolutionarily preserved signature in the primate brain
Researchers from Uppsala University, Karolinska Institute, and the University of Chicago, have determined that there are hundreds of biological differences between the sexes when it comes to gene expression in the cerebral cortex of humans and other primates. These findings, published June 20th in the open-access journal PLoS Genetics, indicate that some of these differences arose a very long time ago and have been preserved through the evolution of primates. These conserved differences constitute a signature of sex differences in the brain.
Researchers find an evolutionarily preserved signature in the primate brain
Researchers have determined that there are hundreds of biological differences between the sexes when it comes to gene expression in the cerebral cortex of humans and other primates. These findings, published June 20th in the open-access journal PLoS Genetics, indicate that some of these differences arose a very long time ago and have been preserved through evolution. These conserved differences constitute a signature of sex differences in the brain.

News discussion:

General Science news

[Home]   [Full version]