"Noisy" Brains

Is your brain “noisy?” Apparently, a noisy brain is a healthy brain. “Noisy” is defined as random brain activity that is not important to mental function. The notion that brain noise quiets down as human beings mature into adults appears to have been overturned by Canadian scientists. The study involved 79 participants (children aged eight to 15 and young adults aged 20 to 33). The participants 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 scored better on the face recognition tasks compared to the children, which was an indication of more stable and accurate cognitive behavior. The young adults' brain signal variability actually increased and became noisier. Lead author Dr. Randy McIntosh, a senior scientist with the Rotman Research Institute at Baycrest said: "What we discovered is that brain maturation not only leads to more stable and accurate behavior in the performance of a memory task, but correlates with increased brain signal variability. This doesn't mean the brain is working less efficiently. It's showing greater functional variability, which is indicative of enhanced neural complexity. So there you have it: random activity that is thought of as noise may actually be a central component of normal brain function.