Researchers have found that teenagers who are bullied by their peers are at higher risk of early-stage psychotic episodes and consequently experience lower levels of a key neurotransmitter in a part of the brain involved in emotion regulation. The finding suggests that this neurotransmitter – a chemical messenger that sends nerve impulses to communicate with a nerve cell – could be a potential target for pharmaceutical interventions aimed at reducing the risk of mental disorders.
Psychosis is a mental state characterized by loss of contact with reality, incoherent speech and behavior, and hallucinations and delusions commonly seen in mental illnesses such as schizophrenia.
Recent studies investigating the link between neurological and psychiatric disorders in certain disorders have shown that individuals who experience first episodes of psychosis, or those with treatable schizophrenia, have lower-than-normal levels of glutamate, a neurotransmitter in the brain’s anterior cingulate cortex (ACC) region. . The ACC is known to play an important role in regulating emotion, decision-making and cognitive control, while glutamate is the most abundant neurotransmitter in the brain and is involved in a wide range of functions including learning, memory and mood regulation.
Changes in glutamate levels have been implicated in various psychiatric disorders, including schizophrenia, depression, and anxiety, and therefore measuring ACC glutamate levels may provide valuable insight into the neural mechanisms underlying these disorders and their treatment.
However, until now, the relationship between changes in glutamate levels in the ACC in individuals at high risk of psychosis, and this and the effects of bullying in adolescents, was clear.
And so researchers at the University of Tokyo used magnetic resonance spectroscopy, or MRS, a type of radiological imaging applied to imaging brain structure and function, to measure glutamate levels in the ACC region of Japanese teenagers. They then measured glutamate levels at a later time point, allowing them to assess changes over time and compare these changes to experiences of bullying or lack thereof, as well as any intentions on the part of those experiencing bullying to seek help.
Adolescent victimization was tracked through questionnaires completed by adolescents. The researchers then used formal psychological measures to assess experiences of being bullied based on that questionnaire, such as tallying the frequency and nature of incidents involving physical or verbal aggression and capturing their impact on overall mental health.
They found that bullying was associated with higher levels of subclinical psychotic experiences in adolescence — symptoms that approach psychosis but do not meet the full criteria for a clinical diagnosis of a psychotic disorder such as schizophrenia. These symptoms or experiences may include hallucinations, paranoia, or radical changes in thinking or behavior, and may have a significant impact on well-being and functioning even in the absence of a diagnosis of mental disorder.
Studying these subclinical psychotic experiences is important for us to understand the early stages of psychotic disorders and to identify individuals who may be at risk of later developing a clinical psychotic illness.”
Naohiro Okada, lead author of the study and project associate professor at the University of Tokyo’s International Research Center for Neurointelligence (a research center under Japan’s World Premier International Research Center Initiative Program)
Importantly, the researchers found that higher levels of these subclinical psychotic experiences were associated with lower levels of anterior cingulate glutamate in early adolescence.
“First and foremost, anti-bullying programs in schools that focus on promoting positive social interactions and reducing aggressive behavior are necessary for their own sake and to reduce the risk of psychosis and its subclinical precursors,” Okada said. “These programs can help create a safe and supportive environment for all students, reducing the likelihood of bullying and its negative consequences.”
Another possible intervention is to provide support and resources for adolescents who have been bullied. This may include counseling services, peer support groups, and other mental health resources that can help teens deal with the negative effects of bullying and develop resilience.
Although Okada’s group identified a potential target for pharmacological intervention, he added that nonpharmacological interventions such as cognitive behavioral therapy or mindfulness-based interventions could also target this neurotransmitter imbalance.