Schizophrenia is a severe, chronic mental illness that affects roughly 1 in 100 Americans. Individuals with schizophrenia frequently struggle with hallucinations, delusions and paranoia. They may also have difficulties regulating their emotions, maintaining relationships, coping with social situations and making complex decisions.
Scientists have been long aware that schizophrenia runs in families. Even though schizophrenia occurs in roughly 1 percent of the population, people who have first-degree relatives with the disorder (i.e., parents and siblings) have an incidence rate of around 10 percent. Having an identical twin with schizophrenia raises the risk tremendously: A person whose identical twin has schizophrenia has a 40 to 64 percent chance of developing it. (Having a fraternal twin with schizophrenia, meanwhile, is comparable to having a non-twin sibling with the disorder.)
How does having a family member with schizophrenia influence your brain? Is your brain itself more vulnerable to the disorder? How?
Having risk for schizophrenia reduces brain’s overall connectivity
A group of researchers led by Marc M. Bohlken, M.Sc., at the University Medical Center Utrecht, the Netherlands, chose to investigate brain connectivity in 70 individual twins (30 identical, 40 fraternal) to determine how being genetically predisposed to schizophrenia alters the brain. In each pair of twins, one twin was diagnosed with schizophrenia, whereas the other twin was free from the disorder. The researchers compared the twins to 130 healthy control twins.
Compared to the healthy control twins, the people with schizophrenia — as well as their twin siblings — had decreased levels of neural connectivity. In other words, certain brain regions weren’t as well-connected as they should have been, suggesting neurons were communicating less effectively. These abnormalities in neural connectivity were particularly prominent in the frontal, striatal and thalamic regions of the brain.
The researchers published their findings in JAMA Psychiatry.
What does this mean?
The results of this study suggest that not only do individuals with schizophrenia have altered neural connectivity, but so do individuals who are at risk of developing schizophrenia, even if they appear to be completely healthy.
Researchers aren’t sure what causes these structural differences, but it may have something to do with genetic mutations. As an example, one genetic mutation may prevent a certain protein in the brain from folding correctly, thereby making connections between neurons weak or faulty. In some instances, these weak or faulty connections may result in schizophrenia. In other instances, they don’t.
Scientists have a long way to go before they’re able to conclusively link certain neural (and genetic) signatures with schizophrenia, but this study brings them one step closer. Hopefully clinicians and researchers will someday be able to understand schizophrenia completely and use that knowledge to craft more thorough and effective treatments.
At Sovereign Health, we use innovative, evidence-based techniques to treat patients with substance dependence along with a variety of mental illnesses, including depression, anxiety, post-traumatic stress disorder, schizophrenia and bipolar disorder. For more information, please contact us at our 24/7 helpline.
About the author
Courtney Lopresti, M.S., is a senior staff writer for the Sovereign Health Group where she uses her scientific background to write online blogs and articles for a general audience. At the University of Pittsburgh, where she earned her Master’s in neuroscience, she used functional neuroimaging to study how the human cerebellum contributes to language processing. In her spare time, she writes fiction, reads Oliver Sacks and spends time with her two cats and bird. Courtney is currently located in Minneapolis. For more information and other inquiries about this article, contact the author at firstname.lastname@example.org.