It has been said that “silence is golden” and it’s definitely true, even in science. New research into how the brain processes information suggests that silence is something the brain needs to process what’s in our surroundings.
Investigators at Neuroscience Research Australian (NeuRA) in collaboration with scientists at the University of New South Wales in Sydney, published work recently that shows that environmental "chatter," which is defined as audio and visual stimuli in a person's immediate environment, can be ignored by the brain. However, periods of silence are crucial for the mind to register and record necessary information from the surrounding input.
So if the surrounding environment is silent, how do we know what the brain is doing? Dr. Ingvars Birznieks and Dr. Richard Vickery found a way to control stimuli to the brain and then record neural activity. By using a series of specific mechanical taps on the fingertips of study participants, and recording nerve impulses, they found that it wasn't always the stimulation that triggered brain activity, but rather the periods of inactivity.
The taps were designed to generate just one nerve impulse in each activated neuron. By manipulating the frequency of the taps, they were able to induce a pattern of nerve impulses in the brain. They were then able to test different patterns and record how the brain encoded the information from the taps.
The sense of touch is something that isn't well understood. When we touch something, ridges on our fingertips create vibrations, but how the brain encodes that input has not been researched thoroughly. There are theories about vibration frequency or patterns of impulses, but the research from Australia showed that it was actually during a period of no input, mostly silence, that the brain was doing most of its work. When Drs. Birznieks and Vickery generated patterns that mimicked touch; it was the intervals between the taps that showed brain activity. Dr. Birznieks stated, "Instead, it was the silent period between bursts that best explained the subjects' experiences. We were hoping to disprove one of the two competing theories, but showing they were both incorrect and finding a completely new coding strategy totally surprised us."
While the researchers were initially skeptical about their findings, they spent a lot of time verifying their results before presenting the work. The brain is a powerful supercomputer, but, as it turns out, some input is processed when stimuli and the brain has some "quiet time" to encode the data correctly. The team hopes that their research will have applications in the field of brain-computer interface technology and high-tech prosthetic limbs, which depend on neural activity that is based on touch. Check out the video below to see more about the study.
Sources: NeuRA Blog Mother Nature Network, Current Biology
