Healthcare (Commonwealth Union) – Schizophrenia is a complex mental health condition, one that profoundly impacts a person’s thoughts, emotions, and actions. It can severely distort how someone perceives the world, making everyday life, social interactions, and employment difficult. Despite what some people believe, schizophrenia isn’t about having “split personalities”—that’s a misunderstanding. The reality is psychosis, a state where a person has trouble telling what’s real from what’s not.
Movies and TV shows often portray schizophrenia as condition where 2 completely different characters are capable of emerging in the same individual.
Scientists at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London have uncovered the first direct evidence that schizophrenia is linked to increased serotonin release in the frontal cortex. The findings also show that this heightened serotonin activity is associated with more severe forms of some of the disorder’s most debilitating symptoms.
Schizophrenia affects roughly one in every hundred people worldwide. Among its most disabling features are social isolation, reduced motivation, and an inability to experience pleasure. These so-called negative symptoms play a major role in preventing people from recovering and leading independent lives, and there are currently no effective treatments available for them.
Published in JAMA Psychiatry, the study lays important groundwork for the development of future therapies aimed specifically at these severe symptoms of schizophrenia.
Although scientists have suggested for more than six decades that excessive serotonin activity may contribute to schizophrenia, this theory had never before been directly examined in individuals living with the condition.
A total of 54 individuals took part in the study, including 26 people diagnosed with schizophrenia and 28 healthy participants who served as controls. Each volunteer underwent two PET imaging sessions using a radiotracer that selectively attaches to serotonin receptors in the brain. Between the two scans, participants were given a single dose of d-amphetamine, a drug known to trigger serotonin release.
When the researchers analysed the results, they observed marked reductions in radiotracer binding following d-amphetamine administration in both the schizophrenia group and the healthy controls. However, the key discovery was that serotonin release was significantly higher in people with schizophrenia within regions of the frontal cortex—areas crucial for motivation, decision-making, and planning—compared with the control group.
Further examination of the data revealed a strong association between increased serotonin release and the severity of negative symptoms, as well as the level of functional impairment, among participants with schizophrenia.
Reflecting on the findings, Dr Martin Osugo, the study’s lead author from King’s IoPPN, indicated that their research offers the first evidence linking serotonin release to the severity of negative symptoms, representing an important advance in this area. He further indicated that they are able to find effective ways to regulate serotonin activity, it may open the door to new treatments targeting these symptoms.
Dr Osugo also pointed out that it is only the initial step however and they will be required to conduct follow-up research to put it to the test.
Professor Oliver Howes, who led the study, says “Schizophrenia often has massive impacts on people’s lives; particularly their motivation and social function. There is little known about what underlies these symptoms and no treatments for this aspect of schizophrenia so we desperately need new approaches. Our findings identify a brain system linked to these symptoms that is a promising candidate for treatment. This gives us hope for the future, but we will need further research funding to develop this.”
The study was funded by the UK Medical Research Council, the Maudsley Charity, the Wellcome Trust, and the National Institute for Health and Care Research (NIHR) Maudsley Biomedical Research Centre.
