title: Increased prepulse inhibition and sensitization of the startle reflex in autistic children.
abstract: The relation between autism spectrum disorders (ASD) and schizophrenia is a subject of intense debate and research due to evidence of common neurobiological pathways in the two disorders. The objective of this study was to explore whether deficits in prepulse inhibition (PPI) of the startle reflex, as usually seen in schizophrenic patients, can be replicated in a group of children with ASD in comparison with a group of matched neuro-typically developed (NTD) controls. An additional aim was to explore possible psychophysiological subgroups within our ASD sample. In a case-control design, 35 ASD patients and 40 matched NTD controls were tested in a psychophysiological test battery. The PPI of the acoustic startle reflex was analyzed in 18 ASD subjects and 34 NTD controls. Habituation and sensitization were analyzed in 23 ASD subjects and 39 NTD controls. In trials with less intense prestimuli (76 dB), patients with ASD did not display the drop in percentage PPI normally found in healthy controls. In addition, ASD patients showed significantly increased sensitization compared with NTD controls. Combined, our results may reflect the hypersensitivity to sensory information in children with ASD. The relation to PPI deficits observed in schizophrenia is not apparent. Future research should study the developmental course of PPI deficits in ASD patients in a longitudinal design.
authors.affiliation: Department of Child and Adolescent Mental Health Odense, Research Unit (University function), Mental Health Services in Region of Southern Denmark, Faculty of Health Sciences, University of Southern Denmark, Glostrup, Denmark.
authors.forename: Gitte Falcher
authors.initials: GF
authors.lastname: Madsen
authors.forename: Niels
authors.initials: N
authors.lastname: Bilenberg
authors.forename: Cathriona
authors.initials: C
authors.lastname: Cantio
authors.forename: Bob
authors.initials: B
authors.lastname: Oranje
mesh_terms: D000161:Acoustic Stimulation; D001143:Arousal; D001767:Blinking; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis* / Q000523:psychology*; D005260:Female; D006185:Habituation, Psychophysiologic; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D012016:Reference Values; D013216:Reflex, Startle; D055139:Sensory Gating
keywords: PPI; auditory processing; autism spectrum disorders; children; sensitization; sensorimotor gating