Stress Response Disrupted in Schizophrenia
Compared with healthy controls and people at high risk for psychosis, people with schizophrenia show a different chemical response to stress, according to a study published in the journal Brain.
“We found a disrupted stress response in people with schizophrenia, which did not occur in either healthy individuals or people at clinical high risk for developing psychosis,” said study lead author Christin Schifani, PhD, postdoctoral research fellow at the Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
The study involved 14 people with schizophrenia, 14 people at clinical high risk for psychosis, and 12 people without mental illness.
In the first part of the study, participants answered math questions without a time limit while a positron emission tomography (PET) scanner measured the neurotransmitter dopamine in the prefrontal cortex, a part of the brain involved in emotional regulation and other complex functions. Saliva samples were also collected to measure levels of cortisol, a hormone released from adrenal glands to help the body handle stress.
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In the next part of the study, participants answered more math questions—but this time under time constraints and amid negative verbal feedback. PET scans were again taken, and saliva samples were collected a second time.
In healthy individuals, dopamine and cortisol levels typically increase during stressful situations. But the relationship between stress and dopamine and cortisol release did not appear in study participants with schizophrenia, researchers reported.
“The fact we see this disrupted stress response in people with schizophrenia but not in people at high risk for psychosis suggests an opportunity to intervene to prevent schizophrenia,” said study senior author Romina Mizrahi, MD, PhD, clinician scientist at the Centre for Addiction and Mental Health. “Developing strategies to cope with stress and build resilience may be the opportunity.”
Schifani C, Tseng HH, Kenk M, et al. Cortical stress regulation is disrupted in schizophrenia but not in clinical high risk for psychosis. Brain. 2018;141(7):2213-2224.
Stress affects people with schizophrenia differently, CAMH study shows [press release]. Toronto, Canada: Centre for Addiction and Mental Health; July 11, 2018.