ⓘ Referred itch
Referred itch is the phenomenon in which a stimulus applied in one region of the body is felt as an itch or irritation in a different part of the body. The syndrome is relatively harmless, though it can be irritating, and healthy individuals can express symptoms. Stimuli range from a firm pressure applied to the skin – a scratch – to irritation or pulling on a hair follicle on the skin. The referred sensation itself should not be painful, it is more of an irritating prickle leading to the compulsion to scratch the area. The stimulus and referred itch are ipsilateral. Also, because scratching or putting pressure on the referred itch does not cause the stimulus area to itch, the relationship between the stimulus and the referred itch is unidirectional. The itching sensation is spontaneous and can cease with continued stimulation.
There are two types of referred itch: normal and pathological purchased. Normal mitempfindung is usually detected in early childhood and is preserved in most, if not all, in a persons life. Acquired or pathological mitempfindung is the result of a lesion of the Central nervous system and lasts only for a short period of time.
Symptoms are variable among affected individuals, but it is widely accepted that the soles of the feet, hands and face are never affected by mitempfindung. There is no evidence of genetic influence on referred itch. Has published study, however, that mentions an affected man whose children were also affected. Much is still unknown about the physiological mechanisms of this phenomenon and adopted no theory is.
Research and information about mitempfindung is limited and dated. Most studies on this topic was held at the end of the 19th century, and the most recent publications occurred in the late 1970-ies. A handful of studies have been conducted in the early 1990-ies, but further data must be collected and interpreted through a deep understanding mitempfindung is achieved.