title: Instrumental measurements of spontaneous dyskinesia and schizotypy in subjects with auditory verbal hallucinations and healthy controls.
abstract: Spontaneous dyskinesia is associated with non-affective psychosis. Few studies investigated dyskinesia in individuals with subclinical psychotic experiences. We examined dyskinesia using instrumental measurements of force variability in 34 individuals with frequent auditory verbal hallucinations but without a clinical psychotic disorder and 31 matched healthy controls. Schizotypy was assessed using the Schizotypal Personality Questionnaire. We found a positive correlation between dyskinesia and schizotypy in the total group. In addition, when using a cut-off point based on the 95th percentile of force variability in the control group, we found a greater proportion of subjects with dyskinesia in the group with auditory verbal hallucinations than in the control subjects. Current findings are in agreement with the concept of psychosis as a continuous phenomenon and with movement disorders being an integral part of psychosis.
authors.affiliation: Psychiatric Centre GGz Centraal, Innova, Research Department, Postbus 3051, 3800 DB Amersfoort, The Netherlands; Faculty of Health Medicine and Life Sciences, University Maastricht, Department of Mental Health and Neuroscience, Postbus 616, 6200 MD Maastricht, The Netherlands. Electronic address: a.willems@ggzcentraal.nl.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Willems
authors.affiliation: University Medical Centre Utrecht, Department of Psychiatry, Postbus 85500, 3508 GA Utrecht, The Netherlands. Electronic address: I.Sommer@umcutrecht.nl.
authors.forename: Iris E C
authors.initials: IE
authors.lastname: Sommer
authors.affiliation: Psychiatric Centre GGz Centraal, Innova, Research Department, Postbus 3051, 3800 DB Amersfoort, The Netherlands; Faculty of Pharmacy, Utrecht University, David de Wiedgebouw, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands. Electronic address: d.tenback@ggzcentraal.nl.
authors.forename: Diederik E
authors.initials: DE
authors.lastname: Tenback
authors.affiliation: Psychiatric Centre GGz Centraal, Innova, Research Department, Postbus 3051, 3800 DB Amersfoort, The Netherlands; University Medical Centre Utrecht, Department of Psychiatry, Postbus 85500, 3508 GA Utrecht, The Netherlands. Electronic address: jeroenkoning@hotmail.com.
authors.forename: Jeroen P F
authors.initials: JP
authors.lastname: Koning
authors.affiliation: Psychiatric Centre GGz Centraal, Innova, Research Department, Postbus 3051, 3800 DB Amersfoort, The Netherlands; Faculty of Health Medicine and Life Sciences, University Maastricht, Department of Mental Health and Neuroscience, Postbus 616, 6200 MD Maastricht, The Netherlands. Electronic address: p.vanharten@ggzcentraal.nl.
authors.forename: Peter N
authors.initials: PN
authors.lastname: van Harten
mesh_terms: D000328:Adult; D020820:Dyskinesias / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D006212:Hallucinations / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D010551:Personality; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D012569:Schizotypal Personality Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D011795:Surveys and Questionnaires
keywords: Auditory verbal hallucinations; Force variability; Psychosis continuum; Spontaneous dyskinesia; Spontaneous movement disorder