Why does denervated skin not wrinkle

As the name suggests, this is where water moves from a low solute concentration to a high solute concentration through the wall of a living cell. On the contrary, evidence suggests that wrinkling does not occur in the denervated areas of the digits []. A similar result is observed when nerves are severed [3]. Current studies have suggested that finger-wrinkling caused by cold moisture exposure is due to digit pulp vasoconstriction, or the narrowing of the blood vessels.

This mechanism is controlled by the autonomic nervous system, part of the peripheral nervous system that is responsible for the control of important functions such as heart rate, digestion and respiration. As a result, the fingertip sees a reduction in volume, leading to the ridge-shaped patterns on the tips of fingers and toes [3]. However, finger-wrinkling still ensues in warm water when vasoconstriction does not occur. Moreover, what is the biological purpose of this mysterious mechanism?

Recent published papers suggest that finger-wrinkling plays a role in assisting us with gripping objects. Much like the texture of rain treads or tires, the grooves resulting from immersed fingertips provide better grip and higher friction in wet conditions. The gaps act as drainage networks for directing extra moisture away from the surface [2]. To test this hypothesis, twenty participants in the age range of 21 — 34 were asked to manipulate a total of 45 objects from one container to another with dry fingers, once with the objects submerged and once when they were dry.

In each case, scientists measured and compared the time it took to transfer all objects. The results showed that moisture-induced wrinkled fingers were more efficient in transferring submerged objects than fingers that were not soaked. However, there was no difference in transfer time in manipulating dry objects with or without wrinkled fingers [3]. The results certainly support the theory that wrinkled fingers provide better grip.

Practically, perhaps this provided our ancestors with an easier time gathering or collecting food in rivers or in wet weather. Similarly, wrinkled toes may have been able to provide superior footing for our ancestors during wet conditions. While this speculation seems to help explain the peculiar biological reaction, it does not address why digits are not constantly wrinkled.

It is postulated that individuals having wrinkled fingers will result in a reduction in fingertip sensitivity and an increase in skin vulnerability. Thus, wrinkled fingers are not evolutionary preserved because the risks of having this feature cannot outweigh its benefits under dry conditions [3]. Mechanical modeling of a wrinkled fingertip immersed in water.

Eight patients with nerve compressions continued to wrinkle and sweat even when two-point discrimination was decreased or absent. These findings indicate that only in patients with a recent complete peripheral nerve lesion does an absence of wrinkling always correspond with a loss of other sensory modalities. The presence of wrinkling in a patient with a nerve compression does not correlate with the patient's sensory modalities. Abstract The phenomenon that denervated skin does not wrinkle or shrivel like normal palmar skin after soaking in water was investigated.

Substances Water Ninhydrin.