Blocked Brain Filter Could Be Source of Mental Issues A Canadian researcher believes the malfunction of a particular type of nerve cell hampers the brain’s ability to filter or inhibit irrelevant information. This breakdown of normal function causes changes in the brain’s prefrontal cortex, according to Julio Martinez-Trujillo, M.D., Ph.D., of McGill University.

Impaired function of this brain region is associated with a failure to filter extraneous information causing a loss of inhibitions, impulsivity, and inappropriate behavior. Similarly, diseases like ADHD, Tourette syndrome, obsessive-compulsive disorder and schizophrenia often report symptoms of “brain clutter” and an inability to focus on relevant things.

New research by Martinez-Trujillo has identified the neurons responsible for this filtering function.

“Contrary to common beliefs, the brain has a limited processing capacity. It can only effectively process about one per cent of the visual information that it takes in,” Martinez-Trujilo said. “This means that the neurons responsible for perceiving objects and programming actions must constantly compete with one another to access the important information.

“What we found when we looked at the behavior of the neurons in the prefrontal cortex, was that an animal’s ability to successfully accomplish a single action in the presence of visual clutter, was dictated by how well these units suppressed distracting information.”

The finding may well be important for identifying the causes and improving the diagnosis and treatments of a wide range of mental disorders.

The study will be published in the journal Neuron.

Source: McGill University