Sex Differences May Be the Key to Advancing Neuroscience Research

(WASHINGTON, DC; 3/14/02) New research shows that understanding sex differences in diseased brains may someday lead to medical breakthroughs in the field of neurologic disorders from schizophrenia to dyslexia. Recently published findings propose that factors involved in producing normal male-female brain variations may also play a role in schizophrenia, a mental illness that causes a range of symptoms including hallucinations, delusions, social withdrawal and dulled emotions. Apparently, gender seems to influence how schizophrenia affects individuals. Men often experience more severe symptoms at earlier ages, have poorer prognoses than women, typically have more severe social and cognitive problems and don't respond as well to medications.

New Findings in Schizophrenia
Jill Goldstein, PhD and her colleagues at Harvard Medical School in Boston are examining whether the clinical differences between men and women with schizophrenia are related to sex-based differences in brain structure and function. The researchers recently used magnetic resonance imaging (MRI) to compare the brains of 40 schizophrenic patients to healthy individuals. Previous studies show that, in general, the brains of schizophrenics are smaller than those of healthy people.

Many experts believe that schizophrenia is the result of a complex interaction between a person's prenatal environment, normal brain development and genes. Goldstein and colleagues speculate that the risk of schizophrenia begins six months before birth and continues into the early newborn stages; laboratory studies in animals show that sex hormones have their strongest effects on the brain during this same time period. Thus, Dr. Goldstein and colleagues hypothesized that effects of sex hormones on the brain occurring simultaneously with risk factors for schizophrenia may result in different brain abnormalities among male and females who go on to develop the disease.

The researchers discovered that the brain abnormalities associated with schizophrenia varied according to sex. Abnormalities occurred primarily in the part of the brain known as the cortex, an area known to differ among healthy men and women, too. According to the researchers, this suggests that the same factors that contribute to normal sex differences may also be involved in the brain abnormalities of schizophrenia.

Dr. Goldstein's findings also suggest that sex differences in brain abnormalities may lead to dissimilar symptoms among male and female schizophrenics. The cortex is involved in language comprehension, verbal tasks, emotion, and social behavior. A number of studies have shown that women with schizophrenia may be less vulnerable to cognitive problems, especially those involving verbal processing, than schizophrenic men.

"There are clearly effects of sex on the brain," commented Charles J. Epstein, MD, Professor of Pediatrics at the University of California San Francisco School of Medicine. "It may be that genetic insults are put on top of normal sex differences, leading to different manifestations of mental disorders among males and females. Getting a grasp on sex differences in mental disorders will help us better understand and prevent these diseases and will hopefully bring about better therapies."

"Understanding how mental illness and developmental disorders affect men and women differently is key to advancing the field of neuroscience," said Phyllis Greenberger, MSW, President and CEO of the Society for Women's Health Research. The Society for Women's Health Research examined sex differences in neuroscience at a scientific advisory meeting last year, covering brain and pain mechanisms, behavioral sex differences, and addiction.

The Society for Women's Health Research is the nation's only not-for-profit organization whose sole mission is to improve the health of women through research. Founded in 1990, the Society brought to national attention the need for the appropriate inclusion of women in major medical research studies and the resulting need for more information about conditions affecting women. The Society advocates increased funding for research on women's health, encourages the study of sex differences that may affect the prevention, diagnosis and treatment of disease, and promotes the inclusion of women in medical research studies. Dr. Donnica Moore has been a member of the Society since 1990 and is a past member of its Board of Directors.

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Created: 3/27/2002  -  Donnica Moore, M.D.