Dementia is a family of diseases that includes some terrible conditions, such as Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). The very structure of the brain is undergoing transformations because of these diseases, and experts have tried to gain a better understanding on how this happens for a long time. Now, a new network mapping technique, which relies on a mathematical model known as the graph theory, promises to offer new insight into the interactions that take place between various portions of the brain when patients have some form of dementia.
The new method, which was detailed in the latest issue of the open-access journal BMC, was developed by experts from the VU University Medical Center, in Amsterdam, the Netherlands, led by scientist Willem de Haan. “By applying concepts from this theory to brain recordings, we can study the dynamic and distributed nature of mental activities. The underlying idea is that cognitive dysfunction can be illustrated by, and perhaps even explained by, a disturbed functional organization of the whole brain network,” de Haan says, quoted by ScienceDaily
Using the new observation method, the team was able to determine that the brains of patients suffering from AD became a lot less structured. That is to say, the optimum balance between local specialization and global integration, which is fairly obvious in healthy individuals that do not suffer from any form of dementia, is distorted in these cases. “We expected to find something along these lines, since in a recent magnetoencephalography (MEG) study with AD patients we found similar changes,” de Haan says of the results.
Essentially, what the new data shows is that the Alzheimer's-related cognitive function deterioration is actually caused by a reduced organization and functional connectivity in the brain. These results conflicted significantly with those obtained from analyzing FTLD independently. In this form of dementia, the brain of patients exhibited higher levels of network organization, which could mean that the mechanisms that trigger the disorders are others than in the case of Alzheimer's.
“This is intriguing, especially since diagnosing FTLD can be difficult. We expect that this approach can be further developed to gain more insight into the different types of dementia and into the relation between brain damage and cognitive problems in general,” de Haan concludes.