Brain Disruptions in Schizophrenia Arise Early, Degrade Connections
24 June 2013. Like mechanics using a computer to diagnosis wiring problems in a car, researchers use brain scanners to look for areas that are different in size, shape, or electrical activity in schizophrenia. Studies find changes in the sizes of different brain regions and in the flow of electrical transmission between them, but rarely do they look at both in the same people. Two new studies attempt to obtain this integrative view and reveal a complex relationship between brain structure and the information coursing through it.
Qiyong Gong and colleagues at the West China Hospital of Sichuan University, Chengdu, were able to study a group of people in the early stages of schizophrenia who were not on antipsychotic medications. This sort of study is rare because people suffering from psychosis usually receive medication right away to quell the symptoms. In their June 4, 2013, report online in the American Journal of Psychiatry, Gong and colleagues find that certain brain regions are already smaller or larger than normal. This argues that these changes underlie the earliest stages of illness rather than being the result of ongoing illness or medication. These bigger- or smaller-than-average regions did not, however, overlap with regions showing abnormal activity—something that suggests that a change in size does not necessarily come with changes in activity flowing in and out of a region.
The second study, led by Martijn Pieter van den Heuvel at the University Medical Center Utrecht in the Netherlands and published online June 5, 2013, in JAMA Psychiatry, mapped brain connections in people who had already had schizophrenia for some years. The researchers were interested in whether people with schizophrenia had the same "hub" structure in their brains. Much like airlines that run all their traffic through a few hub cities, the brain has regions that make a lot of connections and others that are more isolated. The researchers found that the hubs were less well connected to other hubs in people with schizophrenia, suggesting fragmented information processing. They also found a particularly tight correspondence between the structure of connections and the activity flowing between them, which suggests a somewhat rigid information flow chart in schizophrenia. (For more details on this study, see SRF related news story.)—Michele Solis.