This article is more than 5 years old. Information may no longer be current.

People with, without severe mental illness may have similar social brain function

People with and without a schizophrenia spectrum disorder showed differing patterns of neural activity during a socio-emotional task, independent of DSM diagnosis, according to a multisite brain imaging study published in The American Journal of Psychiatry.

However, participants with schizophrenia did not have categorically different social brain function than those without mental illness and instead were classified into different sub-groups, according to a press release.

"We know that, on average, people with schizophrenia have more social impairment than people in the general population," Aristotle N. Voineskos, MD, PhD, of the Centre for Addiction and Mental Health in Toronto, said in the press release. "But we needed to take an agnostic approach and let the data tell us what the brain-behavioral profiles of our study participants looked like. It turned out that the relationship between brain function and social behavior had nothing to do with conventional diagnostic categories in the DSM-5.”

Researchers examined patterns of brain activity during a facial imitate/observe functional MRI task among 109 participants with a schizophrenia spectrum disorder and 70 healthy control participants enrolled in the Social Processes Initiative in Neurobiology of the Schizophrenia(s) study at three different sites. Participants also completed a battery of social cognitive and neurocognitive tests.

Using hierarchical clustering, they assessed whether functional MRI data collected during the performance of the task yielded unique subgroups and whether these subgroups differed in performance on the tests.

Results showed three clusters with distinct patterns of neural activity; however, cluster membership was not linked to diagnosis or scan site. These three clusters were described as having typical, hyperactivating and deactivating profiles.

The researchers found that the largest cluster was typical activators, who demonstrated activity in the canonical fronto-parietal simulation circuit, and that the deactivating group exhibited the highest scores on the social cognitive and neurocognitive tests.

"We think those with over-activated networks may be 'inefficient' in terms of brain activity — they probably struggled more and needed to work harder to do the same task compared with the other groups," Colin Hawco, PhD, of the Centre for Addiction and Mental Health, said in the release. "The 'de-activating' group seemed to show very efficient use of their brains and did better on behavioral tests of social processing as well."

Furthermore, the investigators repeated hierarchical clustering analysis in a replication sample of 32 participants with schizophrenia spectrum disorder, 37 with euthymic bipolar disorder and 39 healthy controls. They found that these participants showed the same three cluster patterns.

“On the basis of these specific patterns of neural engagement, targeted interventions can be tested to enhance social cognitive or neurocognitive test performance in people with psychiatric disorders,” the researchers concluded. “Such patterns of brain function may represent putative circuits that can be directly probed via brain stimulation and can be objectively measured in the scanner as a treatment response marker in people with psychiatric disorders, complementing performance outside the scanner or self-report.” – by Savannah Demko

Disclosures: Voineskos and Hawco report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.