We all know the feeling of a mobile phone vibrating in our hands when announcing an incoming call. If we perceive these vibrations so clearly, it is due to specialized receptors that transduce them into neural signals sent to our brain. But how does the latter encode their physical characteristics? To understand this, neuroscientists from the University of Geneva (UNIGE) have observed what happens in the brains of mice whose forepaws perceive vibrations. They discovered that neurons in the somatosensory cortex are activated in a manner similar to those in the sound-reactive auditory cortex. These results, published in the journal Nature, suggest that feeling a phone vibrate or hearing it ring is ultimately based on the same brain codes.

If you place a glass of water on your desk, you can probably see on its surface the concentric oscillatory motions created by the small movements that occur nearby. These oscillations are caused by vibrations that propagate through the floor, desk, glass and all other solid surfaces. These vibrations are also important sensory stimuli that we use to detect, for example, an approaching train or to identify the familiar step of our office neighbor. «We live surrounded by vibrations that are extremely important in how we perceive the world,» explains Daniel Huber at the Department of Basic Neurosciences at the UNIGE Faculty of Medicine, who led this work. «So we wanted to know how the brain perceives and represents them.».