Human fingertips are extremely sensitive to touch, and new studies show that it is the protruding edges of the fingertips that bring such a high sensitivity.
The researchers conducted an experiment to measure the sensitivity of the nerves in the fingertips They measured. According to this study, human fingers have a sensitivity on the scale of only one protruding edge of the fingertip.
The sensory nerves attached to the receptors are located under the skin, allowing us to detect touch, vibration, pressure, pain, and so on. The human hand has tens of thousands of nerves, each of which has receptors on a very small area of skin called the receptive field.
To map these fields, the researchers tied the hands of 12 healthy people and attached their nails to special plastic clips in order to prevent the hands from moving and to make the experiment as accurate as possible. He then moved a small wheel machine with a 0.4 mm cone to a 7 mm wide area on his finger. The researchers then measured the reaction of each neuron using an electrode mounted on the participating arm.
The researchers specifically sought to map more sensitive points called subfield areas in impact fields. By calculating tactile neurons and mapping them to the fingertip, they found that the width of the detection areas was equal to the width of the edge of a fingertip protrusion.
These sub-fields did not move or change direction when the machine increased or decreased the rotation speed of the cone. This indicates that the sensitive areas of the fingertip are more at the edge of the ridges.
This study demonstrates for the first time the role of the tips of the tips of the fingertips in helping humans touch the world around them. “We all have these sensitive areas, each of which responds to details as small as 0.4 millimeters, about the width of a protruding edge,” says study co-author Ewa Jarocka.
The results of this research in the journal The Journal of Neuroscience It has been published.