Do not disturb: How the brain filters out distractions

You know the feeling? You are trying to dial a phone number from memory… you have to concentrate…. then someone starts shouting out other numbers nearby. In a situation like that, your brain must ignore the distraction as best it can so as not to lose vital information from its working memory. A new paper published in Neuron by a team of neurobiologists led by Professor Andreas Nieder at the University of Tübingen gives insight into just how the brain manages this problem.

The researchers put in a similar situation. The monkeys had to remember the number of dots in an image and reproduce the knowledge a moment later. While they were taking in the information, a was introduced, showing a different number of dots. And even though the monkeys were mostly able to ignore the distraction, their concentration was disturbed and their memory performance suffered.

Measurements of the electrical activity of in two key areas of the showed a surprising result: nerve cells in the signaled the distraction while it was being presented, but immediately restored the remembered information (the number of dots) once the distraction was switched off. In contrast, nerve cells in the parietal cortex were unimpressed by the distraction and reliably transmitted the information about the correct number of dots.

These findings provide important clues about the strategies and division of labor among different parts of the brain when it comes to using the working memory. "Different parts of the brain appear to use different strategies to filter out distractions," says Dr. Simon Jacob, who carried out research in Tübingen before switching to the Psychiatric Clinic at the Charité hospitals in Berlin. "Nerve cells in the parietal cortex simply suppress the distraction, while nerve cells in the prefrontal cortex allow themselves to be momentarily distracted – only to return immediately to the truly important memory content."

The researchers were surprised by the two brain areas' difference in sensitivity to distraction. "We had assumed that the prefrontal cortex is able to filter out all kinds of distractions, while the was considered more vulnerable to disturbances," says Professor Nieder. "We will have to rethink that. The memory-storage tasks and the strategies of each brain area are distributed differently from what we expected."

More information: Simon Jacob, Andreas Nieder: Complementary Roles for Primate Frontal and Parietal Cortex in Guarding Working Memory from Distractor Stimuli. Neuron, 2 July 2014, DOI: dx.doi.org/10.1016/j.neuron.2014.05.009

add to favorites email to friend print save as pdf

Related Stories

Shout now! How nerve cells initiate voluntary calls

Sep 06, 2013

"Should I say something or not?" Human beings are not alone in pondering this dilemma – animals also face decisions when they communicate by voice. University of Tübingen neurobiologists Dr. Steffen Hage and Professor ...

Synchronized brain waves enable rapid learning

Jun 12, 2014

The human mind can rapidly absorb and analyze new information as it flits from thought to thought. These quickly changing brain states may be encoded by synchronization of brain waves across different brain ...

Regulation of attention and concentration in brain unravelled

Aug 11, 2011

(Medical Xpress) -- The prefrontal cortex of the brain is involved in memory processes and the ability to concentrate attentively. Neuroscientists from VU University Amsterdam have shown how and where this occurs in the prefrontal ...

Recommended for you

Researchers unlock mystery of skin's sensory abilities

17 hours ago

Humans' ability to detect the direction of movement of stimuli in their sensory world is critical to survival. Much of this stimuli detection comes from sight and sound, but little is known about how the ...

Tackling neurotransmission precision

Dec 18, 2014

Behind all motor, sensory and memory functions, calcium ions are in the brain, making those functions possible. Yet neuroscientists do not entirely understand how fast calcium ions reach their targets inside ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.