title: Auditory false perception in schizophrenia: Development and validation of auditory signal detection task.
abstract: Auditory hallucinations constitute an important symptom component in 70-80% of schizophrenia patients. These hallucinations are proposed to occur due to an imbalance between perceptual expectation and external input, resulting in attachment of meaning to abstract noises; signal detection theory has been proposed to explain these phenomena. In this study, we describe the development of an auditory signal detection task using a carefully chosen set of English words that could be tested successfully in schizophrenia patients coming from varying linguistic, cultural and social backgrounds. Schizophrenia patients with significant auditory hallucinations (N=15) and healthy controls (N=15) performed the auditory signal detection task wherein they were instructed to differentiate between a 5-s burst of plain white noise and voiced-noise. The analysis showed that false alarms (p=0.02), discriminability index (p=0.001) and decision bias (p=0.004) were significantly different between the two groups. There was a significant negative correlation between false alarm rate and decision bias. These findings extend further support for impaired perceptual expectation system in schizophrenia patients.
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Harleen
authors.initials: H
authors.lastname: Chhabra
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Selvaraj
authors.initials: S
authors.lastname: Sowmya
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Vanteemar S
authors.initials: VS
authors.lastname: Sreeraj
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Sunil V
authors.initials: SV
authors.lastname: Kalmady
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Venkataram
authors.initials: V
authors.lastname: Shivakumar
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Anekal C
authors.initials: AC
authors.lastname: Amaresha
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Janardhanan C
authors.initials: JC
authors.lastname: Narayanaswamy
authors.affiliation: The Schizophrenia Clinic, Department of Psychiatry & Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India. Electronic address: venkat.nimhans@yahoo.com.
authors.forename: Ganesan
authors.initials: G
authors.lastname: Venkatasubramanian
mesh_terms: D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D005260:Female; D006212:Hallucinations / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests / Q000592:standards*; D011594:Psychometrics / Q000295:instrumentation*; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000503:physiopathology*; D017603:Signal Detection, Psychological / Q000502:physiology*; D055815:Young Adult
keywords: Auditory hallucinations; Auditory signal detection; False alarm; Schizophrenia