title: Psychogenic tics: diagnostic value of the placebo test.
abstract: Motor tics are characterized by abrupt onset of brief, unsustained focal movements that are usually preceded by a premonitory sensation and are suppressible. Psychogenic tics (pseudotics) are rarely described. It may not be easy to distinguish organic from functional tics because they can coexist. Using a case illustration, the value of a "staged" placebo test in aiding the diagnosis of psychogenic tics is described. In addition, a concise summary of the clinical phenomenology of tics and the diagnosis and management of psychogenic movement disorders is provided.
authors.affiliation: Department of Neurology, Singapore General Hospital, National Neuroscience Institute, SingHealth Research. gnrtek@sgh.com.sg
authors.forename: Eng-King
authors.initials: EK
authors.lastname: Tan
mesh_terms: D002648:Child; D006801:Humans; D008297:Male; D015990:Placebo Effect; D010919:Placebos; D020323:Tics / Q000175:diagnosis* / Q000523:psychology*; D014741:Video Recording
chemical_list: D010919:Placebos