What Areas of the Brain are Affected by Schizophrenia?
Disruptions in brain structures and brain function may be catalysts for schizophrenia. Here’s what we know about how specific areas of the brain are affected.
Symptoms of schizophrenia may include disorganized thinking, difficulty making decisions and expressing emotions, hallucinating and more. To better understand the illness and how to treat it, doctors have been using brain imaging to identify areas of the brain affected by schizophrenia.
Brain scans can provide details about the parts of the brain, their functions and connectivity—how the different parts of the brain communicate with the rest of the body. But they can't reveal everything. For instance, despite decades of research, brain scans cannot conclusively diagnose schizophrenia.
"Brain imaging and other laboratory data can be collected to rule out other medical conditions, but there is no single diagnostic or blood test that can conclusively diagnose schizophrenia," explains [Adrian Preda, MD](http://www.ucihealth.org/find-a-doctor/p/adrian-preda, [email protected]), a professor of clinical psychiatry at the University of California Irvine. He notes that while there is no specific change occurring anywhere in the brain that is seen only in schizophrenia, many studies do show consistencies in people with schizophrenia, including brain shrinkage (known as general cortical atrophy), enlargement of ventricles (cavities in the brain filled with fluid) and decreased brain connectivity.
Read more: Schizophrenia Types of Hallucinations
Brain Areas Affected by Schizophrenia
What imaging shows is that certain areas of the brain are more frequently affected in schizophrenia. They include:
Prefrontal Region. Responsible for problem-solving and decision-making, the prefrontal cortex is one of the last areas of the brain to fully mature, according to the National Institutes of Health (NIH). This area is where personality is formed. It's also where we process everything we witness as we are witnessing it. In a split second, we're able to compare incoming stimulus to previous experiences and react appropriately. Damage to the prefrontal region can lead to symptoms associated with schizophrenia, such as the lack of self-regulation, apathy, lack of motivation, changes to personality and hallucinations.
Hippocampus. Responsible for memory functions including receiving, storing and recalling information, the hippocampus also impacts decision-making and mood, according to the NIH. Research published in the journal Psychiatry Research in April 2016 found that, compared with healthy individuals, people with schizophrenia have a smaller hippocampus. They may also experience progressive deterioration of gray matter in the hippocampus over time.
Read more: Common Types of Delusions in Schizophrenia
Amygdala. This region of the brain is responsible for emotional and social processing. As with the hippocampus, the amygdala of individuals with schizophrenia is smaller than in healthy individuals. And there's a correlation between smaller amygdala volume and memory in schizophrenia, according to the Psychiatry Research study. This may occur because of changes that occur early in the illness and lead to disrupted connectivity in the brain.
Basal Ganglia. Responsible for fine motor coordination and cognitive processing, the basal ganglia are tasked with processing internal and external cues in order to determine how to physically respond, according to a report in the journal F1000 Research in January 2019. This area of the brain initiates and stops specific voluntary movements and also helps control emotions, language, decision-making and working memory.
Cerebellum. Responsible for fine motor coordination and cognitive processing, the cerebellum also plays a role in helping to control the brain's reward processing response. According to NIH, abnormalities in the cerebellum have been linked to schizophrenia, along with other mental health diseases, and specifically to problems with motivation, social and emotional behaviors and reward learning.
When the various parts of the brain stop connecting properly for any reason, wires can get crossed and brain function is affected. When this happens as part of a mental illness, symptoms can begin to appear. And, as a study published in June 2019 in eNeuro found, the level of impairment and connectivity in the brain may influence how severe the cognitive symptoms of a mental illness like schizophrenia are.