Failure to deactivate specific brain networks could explain diseases like Alzheimer's or depression

Researchers from the Institute of Biomedical Research of Bellvitge (IBIDELL) have shown how brain areas interact as if the person is resting or active. Networks active when resting should be deactivated when awake, but a dysfunction in this process may be behind some diseases. The study has been published in the journal ‘PLoS ONE’.


August 12, 2011 11:41 PM

Barcelona (ACN) .- Researchers at the Institute of Biomedical Research of Bellvitge (IBIDELL) have shown that there are areas of the brain that are active when a person is at rest and are disabled when an activity starts. According to a study published in the journal PLoS ONE, “dysfunction in the deactivation of these networks may explain why diseases such as Alzheimer's or depression occur”, explains Narcís Cardoner, co-author of the study. In healthy people these areas, known as the default-mode-network is disabled during an emotional or cognitive task. The network necessarily reduces its activity in one area in order to activate a different region, which is responsible for initiating a new task.

The IBIDELL researcher and co-author of the study, Narcís Cardoner, explained that this discovery is important because it presents a better understanding of the mechanisms of the brain, and presents the possibility that "an altered performance of this network is linked to several diseases such as schizophrenia, depression, obsessive-compulsive disorder or Alzheimer's"

Cardoner considers it likely that these patients may experience a malfunction within the network when brain activity is disabled despite the person not being at rest. Learning how to regulate this activity would improve the prognosis of certain diseases, but Cardoner has warned that this is "only the beginning."

The research was led by Jose Manuel Menchón and was conducted through the monitoring of 50 adult brains, using magnetic resonance imaging to determine active and inactive states.

Test were done while performing an emotional task, such as matching faces to expressive emotions,  and complex cognitive tasks, such as writing the name of a colour with a pen of another colour.

In the case of complex cognitive tasks, research has also shown that the deactivation extends beyond the default mode network and runs to the posterior insular cortex.