What happens in the brain when simply hearing becomes listening? To answer this question, researchers at the University of Basel have traced the neuronal fingerprint of the two types of sound processing in the mouse brain.
It is intuitively clear to us that there is a difference between passive hearing and active listening. Attention and an animated state, but also movement, play a role in how sound processing in the brain adjusts accordingly. Neuroscientists Professor Tania Rinaldi Barkat and Dr. Gioia De Franceschi from the Department of Biomedicine at the University of Basel have provided an accurate account of what happens in this process in the journal Cell Reports.
For their study, the researchers examined the activity of neurons in four different areas in the brains of mice known to be involved in increasingly complex sound processing. During the experiment, the animals were either passively hearing the sounds played to them, or actively listening to them to receive a reward for detecting the sounds.
Ten distinct types of activity change
It was shown that the majority of neurons changed their activity when switching between hearing and listening. “But this doesn’t mean that all neurons behaved the same way,” explains De Franceschi. “We actually found ten distinct and specific types of activity change.”
While most of the neurons showed a change that was probably related to varying levels of attention, some of them also showed patterns of activity that were related to the arousal level of the mice, their movement, the availability of a reward, or a combination of these factors.