Researchers Discover New Details in the Brain's Ability to Pay Attention

In a landmark study, a team of researchers describe in greater detail than ever before just how the brain manages to pay attention to certain things despite constant environmental noise.

The ability to pay attention -- that is, to focus on relevant information while filtering out distractions -- is a key brain function and crucial to people's ability to interact with their environment.

Still, despite this important role in everyday life and many studies regarding the behavior, the exact cellular mechanisms responsible for it have long remained a mystery.

In a study appearing in the journal Nature, however, a team of scientists from Dartmouth's Geisel School of Medicine and the University of California Davis explain how they were able to study communications between synaptically connected neurons under conditions where subjects shifted their attention toward or away from visual stimuli that activated the recorded neurons.

Using this highly sensitive measure of attention's influence on neuron-to-neuron communication, they report they were able to demonstrate that attention operates at the level of the synapse to improve sensitivity to incoming signals, sharpen the precision of these signals and selectively boost the transmission of attention-grabbing information while reducing the level of potentially attention-disrupting material.

The results point to a novel mechanism by which attention shapes perception by selectively altering presynaptic weights to highlight sensory features among the constant bombardment of sensory input.

"While our findings are consistent with other reported changes in neuronal firing rates with attention, they go far beyond such descriptions, revealing never-before tested mechanisms at the synaptic level," study co-author Farran Briggs, assistant professor of physiology and neurobiology at the Geisel School of Medicine, said in a press release.

As a result, the researchers believe science is one step closer to helping people with attention deficits resulting from brain injury or disease, possibly leading to improved screening and new treatments.