Researchers have discovered differences in functional brain connectivity between individuals with and without schizophrenia, shedding light on the neural basis of the disorder.
The brain’s cortex controls sensory information and its alteration can cause symptoms such as loss of executive control in schizophrenia. Through advanced mathematical and brain imaging techniques, the study revealed deficiencies in the organizational patterns that separate visual and sensorimotor pathways in people with schizophrenia.
This deterioration was associated with the clinical symptoms of the disease, which provided information on its mechanisms.
Important facts:
- Schizophrenia can arise from a disruption of brain connectivity and functional integration.
- The study found that the organizational pattern separating the visual and sensorimotor pathways is significantly affected in people with schizophrenia.
- Changes in brain organization may provide important information about the progression and mechanisms of schizophrenia.
Schizophrenia, a neurodevelopmental disorder whose symptoms include psychosis, is thought to arise from alterations in brain connectivity and functional integration.
Now, a new study in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging finds differences in functional brain connectivity in people with and without psychosis and schizophrenia that may help researchers understand the neural basis of this disease.
The cortex of the brain is organized hierarchically, anchored at one end by the sensorimotor cortex and at the other by multimodal association areas, which have the function of integrating incoming sensitive information with internal and external sensitive signals. The loss of executive control in schizophrenia may be due to disruption of this hierarchical signaling.
Alexander Holmes, a PhD seeker at Monash University who led the study, said “ We used brain imaging and new fine ways to probe the hierarchical association of the smarts of individuals with early psychosis and established schizophrenia. This organization is important for brain health as it controls how effectively we can respond to and process stimuli from the outside world.
The experimenters used resting- state functional glamorous resonance imaging( fMRI) to measure slants, an estimate of interregional functional coupling. Previous work had suggested that the primary sensory-fugue gradient was altered in schizophrenia, but the present study showed that secondary processing of the sensorimotor-visual gradient was impaired in people with the disease.
Holmes said: “We found that the organizational pattern separating the visual and sensorimotor pathways is significantly altered in individuals with schizophrenia, but not in individuals with early psychosis. We then found that this impairment is associated with the clinical and behavioral consequences of schizophrenia.” He explains the symptoms.
” Our results punctuate that changes in brain association give precious information about the mechanisms of schizophrenia, helping us more understand the complaint and how it progresses.”
Cameron Carter, MD, editor of Biological Psychiatry Cognitive Neuroscience and Neuroimaging, said of the work” These new approaches to testing fine models of circuit association in the mortal brain are beginning to reveal the nature of the dislocation of neural integration. There are underpinning psychotic symptoms in people with schizophrenia.
” Targeting these changes provides a new focus on how we suppose about developing treatments for this frequently delicate- to- treat complaint.”
Background
The cerebral cortex is organized hierarchically along an axis extending from unimodal sensorimotor areas to cross-modal association areas. This hierarchy is often represented by low-dimensional embeddings, called gradients, of projections of interregional functional coupling measured with resting-state functional magnetic resonance imaging (fMRI). Such analyzes can provide insights into the pathophysiology of schizophrenia, which is often related to dysfunctional interactions between association and sensorimotor areas.
Methods
To investigate alterations in hierarchical cortical function at different stages of psychosis, we applied diffusion map embeddings to two independent fMRI datasets: one consisting of 114 patients with early psychosis and 48 controls, and the other consisting of those with established schizophrenia and 121 controls. Patients were included. We then analyzed the primary sensory-fugal and secondary visual-sensorimotor gradients for each participant in both data sets.
Result
There were no significant differences in indigenous grade scores between cases with early psychosis and controls. Cases with established schizophrenia showed significant differences in the secondary, but not primary, grade relative to controls. Graded differences in schizophrenia were characterized by reduced network dispersion in the dorsal (p FDR < 0.001), visual (PFDR = 0.003), frontoparietal (PFDR = 0.018), and limbic (PFDR = 0.020) and low attention networks. network dispersion.
Conclusion
These findings indicate that differences in cortical hierarchical function occur along a secondary visual-sensorimotor axis rather than a primary sensory-fugal axis, as previously thought. The lack of differences in early psychosis suggests that visuosensory-motor abnormalities may emerge as the disease progresses.
