Georges Gilles de la Tourette described symptoms in 1984.
=== Onset and progression ===There is no typical case of Tourette syndrome, but the age of onset and the severity of symptoms follow a fairly reliable course
 There are no specific medical or screening tests that can be used to diagnose Tourette's; the diagnosis is usually made based on observation of the individual's symptoms and family history, and after ruling out secondary causes of tic disorders (tourettism)

