Researchers have identified weakened beta-band brain signals that may help explain why schizophrenia can affect perception, movement, language and other aspects of behavior at the same time. In a study of 50 participants, the most pronounced abnormalities were associated with difficulty judging the timing of sights and sounds, more disorganized speech and more severe clinical symptoms, suggesting that apparently separate features of the disorder may share an underlying disruption in information processing.
Schizophrenia is a complex mental illness that can alter how people experience the world, interact with their surroundings and communicate. These effects are often studied as separate symptoms, but the new findings suggest they may be connected through a common brain mechanism.
The research was conducted by scientists at McGill University, the McConnell Brain Imaging Center, the Université de Montréal, the Université de Montréal Health Center Research Center and the Douglas Research Center.
Weakened brain signals linked to several symptoms
The researchers examined beta-band brain activity in 25 people diagnosed with schizophrenia and 25 healthy participants. Beta-band activity consists of rhythmic electrical patterns involved in information processing, perception and motor coordination.
Participants completed a task that measured how accurately they could judge the timing of visual and auditory information. The researchers also analyzed their speech for signs of disorganized thinking or communication.
Compared with the control group, participants with schizophrenia showed weaker and slower beta-band activity. Those with the most pronounced abnormalities in these signals generally had greater difficulty processing the timing of sights and sounds, more disorganized speech and more severe clinical symptoms.
These three features of schizophrenia are usually investigated independently. Their association with changes in the same brain signals suggests that shared processes may contribute to the disorder’s diverse effects.
A possible link between brain models and symptoms
The brain constantly uses incoming sensory information to develop and update its understanding of the surrounding environment. This process helps people interpret what they see and hear, predict events and adjust their actions. The findings suggest that disruption of this process may help explain why schizophrenia affects multiple aspects of perception and behavior.
Researchers measured brain activity using high-resolution magnetoencephalography, or MEG. The technique detects the tiny magnetic fields generated by electrical activity in the brain, allowing scientists to track changes in neural signals with high precision. The scans were performed at the McConnell Brain Imaging Center at the Montreal Neurological Institute Hospital, known as The Neuro.
“This is a first showing that measuring how the brain works, and in particular how it builds and modifies its own models of the world, may help us understand the commonalities behind the confusing array of symptoms seen in diseases like schizophrenia. We present preliminary but compelling evidence,” said the study’s lead author, Dr. Lena Palaniyappan, professor of psychiatry at McGill University and director of the Center of Excellence in Adolescent Mental Health at Douglas Hospital.
“What struck us was that the same weakened brain signals continued to appear everywhere we looked, whether the patients were processing sound, processing vision, or completing movements,” said Shi (Tiana) Wei, lead author of the study and a postdoctoral fellow in the McGill Department of Psychiatry and the Douglas Research Center. “Seeing the same pattern in these different areas suggests that there may be a common underlying process linking the symptoms.”
Potential for earlier identification
The findings could eventually help researchers identify young people at high risk of developing psychosis. Psychosis involves a disruption in how a person perceives or interprets reality and may include hallucinations and delusions.
Early identification is important because the first signs of schizophrenia often appear during adolescence but may go unrecognized for extended periods.
“The first signs of schizophrenia begin in adolescence, but this is often overlooked for a long time. If confirmed in a larger sample, this finding could help identify among young people seeking mental health help who may need extra support to prevent psychosis,” Palaniyappan said.
The researchers emphasized that the results are preliminary. The study included only 50 participants, and larger studies conducted by independent groups will be needed to determine how reliably the brain signals are associated with language impairment and overall symptom severity.
“This is the first moderately sized study, and we need to test it in a larger, independent sample to be confident of the association between speech and clinical severity,” Wei said.
If future research confirms the findings, beta-band activity could become a useful tool for identifying people who need early support. Wei also suggested that these brain signals could be investigated as a possible target for future schizophrenia treatments.
Source: www.sciencedaily.com