Our Sense of Touch: So Sharp It Spans a Single Fingerprint RidgeEach of tens of thousands of sensory neurons is tuned in to a tiny surface area of the skin
If you’ve ever wondered why your sense of touch, even on the dead surface of the skin, seems so acute, researchers looked into that and shared their findings last year:
Sensory neurons in the finger can detect touch on the scale of a single fingerprint ridge, according to new research published in Journal of Neuroscience.
The hand contains tens of thousands of sensory neurons. Each neuron tunes in to a small surface area on the skin — a receptive field — and detects touch, vibration, pressure, and other tactile stimuli. The human hand possesses a refined sense of touch, but the exact sensitivity of a single sensory neuron has not been studied before.Society for Neuroscience, “Fingerprints Enhance Our Sense of Touch” at Neuroscience News (March 15, 2021) The paper is open access.
The team (Ewa Jarocka et al.) measured the electrical activity generated by sensory neurons in human fingertips when they were stimulated by raised dots that were swept over the skin. Thus the detection areas could be calculated and mapped onto the fingerprints. The detection areas are anchored to the ridges but they overlap and the information is shared — which is why our sense of touch at our fingertips is so acute.
You may also wish to read: Single neurons perform complex math — even in fruit flies. The fly wants something simple — to avoid getting swatted or eaten, for example — but that requires some algebra. The fly’s specialized neurons either multiply or divide incoming signals in order to pinpoint the location of a sound or the direction of movement.
Hat tip: Creation-Evolution Headlines