Washington, July 4 : Canadian scientists have shown that random brain activity that is not important to mental function, often considered to be 'noise', is actually indicative of a healthy brain.
Experts at the Rotman Research Institute at Baycrest say that their findings overturn the intuitive notion that the brain noise quiets down as children mature into adults, and become more efficient and consistent in their cognitive processing.
"What we discovered is that brain maturation not only leads to more stable and accurate behaviour in the performance of a memory task, but correlates with increased brain signal variability," said lead author Dr. Randy McIntosh, a senior scientist with the Rotman Research Institute at Baycrest.
"This doesn't mean the brain is working less efficiently. It's showing greater functional variability, which is indicative of enhanced neural complexity," Dr. McIntosh added.
A research article published in the Public Library of Science - Computational Biology suggests that the study involved 79 participants representing children aged eight to 15, and young adults aged 20 to 33.
All the subjects completed a series of face memory tasks to measure their ability to recall faces with accuracy.
The researchers collected the participants' electroencephalography (EEG) recordings to measure their brain signal activity, while they were performing the task.
They found the young adults to score better on the face recognition tasks compared to the children, which was an indication of more stable and accurate cognitive behaviour.
The researchers also observed that the young adults' brain signal variability actually increased and became noisier.
"These findings suggest that the random activity that we think of as noise may actually be a central component of normal brain function," said Dr. McIntosh.