Subgroups of Schizophrenia Linked to Various Brain Anomalies
Different anomalies in the corpus callosum were associated with different symptoms in the schizophrenic participants.
An international team of researchers has linked specific symptoms of schizophrenia with various anatomical characteristics in the brain, according to research published in NeuroImage.
By analyzing the brain's anatomy with magnetic resonance imaging (MRI), researchers from the University of Granada, Washington University in St. Louis, and the University of South Florida have demonstrated the existence of distinctive subgroups among patients with schizophrenia who suffer from different symptoms.
These findings could herald a significant step forward in diagnosing and treating schizophrenia.
To perform the study, the researchers conducted the MRI technique “diffusion tensor imaging” on 36 healthy participants and 47 schizophrenic participants.
The researchers found that tests on schizophrenic participants revealed various abnormalities in parts of the corpus callosum, a bundle of neural fibers that connects the left and right cerebral hemispheres and is essential for effective interhemispheric communication.
Different anomalies in the corpus callosum were associated with different symptoms in the schizophrenic participants. An anomaly in one part of the brain structure was associated with strange and disorganized behavior; another anomaly was associated with disorganized thought and speech, as well as negative symptoms such as a lack of emotion; and other anomalies were associated with hallucinations.
In 2014, this same research group proved that schizophrenia is not a single illness. The team demonstrated the existence of 8 genetically distinct disorders, each with its own symptoms. Igor Zwir, PhD, and Javier Arnedo from the University of Granada's Department of Computer Technology and Artificial Intelligence found that different sets of genes were strongly linked with different clinical symptoms.
“The current study provides further evidence that schizophrenia is a heterogeneous group of disorders, as opposed to a single illness, as was previously thought to be case,” Dr Zwir said in a statement.
While current treatments for schizophrenia tend to be generic regardless of the symptoms exhibited by each patient, the researchers believe that in the future, analyzing how specific gene networks are linked to various brain features and specific symptoms will help develop treatments that are adapted to each patient's individual disorder.
To conduct the analysis of the gene groups and brain scans, the researchers developed a new, complex analysis of the relationships between different types of data and recommendations regarding new data. The system is similar to that used by companies such as Netflix to determine what movies they want to broadcast.
“To conduct the research, we did not begin by studying individuals who had certain schizophrenic symptoms in order to determine whether they had the corresponding brain anomalies,” said Dr Zwir in a statement. “Instead, we first analyzed the data, and that's how we discovered these patterns. This type of information, combined with data on the genetics of schizophrenia, will someday be of vital importance in helping doctors treat the disorders in a more precise and effective way.”
Arnedo J, Mamah D, Baranger DA, et al. Decomposition of brain diffusion imaging data uncovers latent schizophrenias with distinct patterns of white matter anisotropy. NeuroImage. 2015; doi:10.1016/j.neuroimage.2015.06.083.