Scientists Find How Brain Filters Out Distractions
Researchers from New York University’s Langone Medical Center believe they have found the area of the brain responsible for ignoring distractions.
The findings, they say, may help narrow down which defects might be responsible for disorders such as autism, ADHD, and schizophrenia.
The team based their study on a 30-year-old key piece of research from Dr. Francis Crick which suggested the thalamus of the brain works with the cortex to prepare a person to focus on a task at hand.
They added that the brain typically only focuses on a small amount of sensory information to guide behavior, leaving out large amounts of information that it finds ‘unimportant.’ However, in neurological disorders, this process may be broken, leading to an overload of information on the brain and lack of control of sensory input.
To test their theories, the team trained mice to either focus on or ignore distractions. Mice were trained to use light or sound as a cue as to which door had a milk reward. Before each cue, a sound was made to signal the mice to look out for the correct one that led to a reward. Mice had to ignore irrelevant cues in order to focus on the right one. However, they used genetically modified mice, where light would either activate or inhibit certain neurons.
When testing TRN neurons, which are involved with vision, mice struggled to concentrate on the light cue when TRN was tuned on, and struggled to focus on sound cues when TRN was turned off. TRN stands for inhibitory thalamic reticular nucleus (TRN) cells, which are located deep inside the brain.
Based on the results, the team discovered that visual TRN signal dysfunction makes unimportant information more distracting to the brain.
The findings, published in Nature, suggest how certain circuits of the brain might decide which sensations we pay attention to. This could help scientists pinpoint which areas of the brain to focus on when studying neurological disorders.