User:Mr. Ibrahem/Synesthesia
Medical condition / From Wikipedia, the free encyclopedia
Synesthesia is a phenomenon in which stimulation of one sensory or cognitive pathway also leads to involuntary experiences in another sensory or cognitive pathway.[1][4] The most common stimulations are letters, numbers, or words; and the most common experiences are colors or textures.[1] Other types may involve days, music, taste, or people.[1] People may have more than one type.[1]
Synesthesia | |
---|---|
Other names | Synaesthesia[1] |
Some of those affected perceive certain letters and numbers as also colors. | |
Specialty | Psychiatry, neurology |
Symptoms | Experiencing one sensation as an additional sensation[1] |
Types | At least 61[2] |
Causes | Unclear[3] |
Risk factors | Family history, sensory loss, LSD[1] |
Differential diagnosis | Illusion, hallucination[1] |
Frequency | ~4% of people[4] |
The cause is unclear.[3] Cases may develop earlier in life or be acquired following a precipitating event.[1] Risk factors include family history, sensory loss such as blindness, and substances like lysergic acid diethylamide (LSD).[1] About 40% of cases have a first-degree relative who is affected.[4] The underlying mechanism may involve decreased neuronal inhibition or decreased pruning of nerve connections.[5] There remains ongoing discussion on to how best define the condition.[1][2]
Between 2% and 20% of people are affected to some degree.[1] Males and females appear to be affected with similar frequency.[1] The condition may result in benefits in cognitive processing such as creative ability.[4] Some have used it to help with memorization.[4]
The earliest recorded case may be from 1690 by philosopher John Locke, who described a blind man who experienced the color scarlet when he heard the sound of a trumpet.[6] However, some dispute if what Locke described was an actual instance of the condition or a metaphor.[7] The first medical account is attributed to German physician Georg Tobias Ludwig Sachs in 1812.[7][8][9] The term is from the Ancient Greek σύν syn, meaning "together", and αἴσθησις aisthēsis, meaning "sensation".[10] Those who have a long term history of such experiences are known as synesthetes.[11]