Some science behind the scenes
Paraesthesia is the medical name for the sensation of tingling, tickling, pricking, or burning of a person's skin with no apparent long-term physical effect. The most familiar kind of temporary paresthesia is the sensation known as "pins and needles" or of a limb "falling asleep". A less well-known but still fairly common paresthesia is formication. Formication is the medical term for a sensation that exactly resembles that of small insects crawling on (or under) the skin.
The ultimate cause is nerve system damage, which results in the nerves sending inaccurate signals to the brain. As the brain also has nerves in it, brain damage can also cause paraesthesia. For this reason, stroke survivors and those with Traumatic Brain Injury (TBI) may experience paresthesia from damage to the central nervous system.
For more details see Tactile hallucinations.
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