Our brain operates much the same whether active or at rest. Scientists now say studying resting brains could make it easier to identify the underlying causes of mental conditions such as schizophrenia and bipolar disorder.
“We can now observe people relaxing in the scanner and be confident that what we see is there all the time.”
Cole at first was worried the research might show instead that the brain reorganizes itself for every task.
“If that had been the case, we would have had less hope that we could understand mental illness in our lifetime.”
Scientists can now make their search for causes of mental illness more focused, and Cole suggests at least one target of opportunity. The prefrontal cortex is a portion of the brain involved in high level thinking, as well as remembering what a person’s goal is and the task being performed.
It would be useful to explore whether connectivity between the prefrontal cortex and other areas of the brain is altered—while the brain is at rest—in people with severe mental illness.
“And then we can finally say something fundamental about what’s different about the brain’s functional network in schizophrenia and other conditions.”
Those differences, in turn, could explain certain symptoms. For instance, what if a patient has visual hallucinations because poor connectivity between the prefrontal cortex and the portion of the brain that governs sight causes the hallucinations to override what the eyes actually see?
Cole suggests that’s just one of the questions that analysis of the brain at rest might help to answer. Others include a person’s debilitating beliefs, such as overly negative self-assessment when depressed.
Opportunities to find better ways to improve patients’ lives might then follow. Current medications for severe mental illness, when they help at all, typically do not relieve cognitive symptoms, Cole says.
It is possible the drugs will reduce hallucinations or depressing thoughts, but patients continue to have difficulty concentrating on the task at hand, and often find it hard to find or hold a job. Even solving that one issue would be a major step forward, he says.
Michael W. Cole, Danielle S. Bassett, Jonathan D. Power, Todd S. Braver, Steven E. Petersen Intrinsic and Task-Evoked Network Architectures of the Human Brain Neuron, Volume 83, Issue 1, p238–251, 2 July 2014 DOI: http://dx.doi.org/10.1016/j.neuron.2014.05.014
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