14 DAY TRIAL // According to a study published in the February 26th issue of the journal Neuron, a publication edited by Cell Press, the human brain has the ability to employ a very sophisticated filtering mechanism, aimed at preventing unimportant sounds from being processed and consuming brain power, especially during very complex cognitive tasks. This process is very important, because it allows people to concentrate and focus on a very important thing, while at the same time remaining oblivious to particulars that might distract them.
Another very important find that the study details is the fact that a disruption of the inhibitory pathways that are involved with the filtering process can lead to the onset of mental illnesses such as schizophrenia, when people think they hear all sorts of things, although everything is dead silent around them.
“The ability to keep track of information and one's actions from moment to moment is necessary to accomplish even the simple tasks of everyday life. Equally important is the ability to focus on relevant information and ignore noise,” Boston University and School of Medicine investigator Dr Helen Barbas, who is also the senior author of the Neuron paper, argues.
“The primate dorsolateral prefrontal cortex (DLPFC) and anterior cingulated cortex (ACC) are brain regions that focus attention on relevant signals and suppress noise in cognitive tasks. However, their synaptic communication and unique roles in cognitive control are largely unknown,” she adds.
The ACC is the part of the brain that is directly involved in suppressing “background noises” when a person is involved in taking difficult decisions, or in reviewing, for example, a paper that needs a lot of attention. According to previous studies, which have measured the levels of activity in this area using functional Magnetic Resonance Imaging (fMRI), it's dysfunctions of the ACC that can trigger schizophrenia and other related diseases.
“The present data provide a circuit mechanism to suggest that pathology in the output neurons of ACC in schizophrenia might reduce excitatory drive to inhibitory neurons of dorsolateral prefrontal cortices, perturbing the delicate balance of excitation and inhibition,” Barbas concludes.