title: Uncontrollable voices and their relationship to gating deficits in schizophrenia.
abstract: BACKGROUND
  Prepulse inhibition (PPI) of the startle response refers to the ability of a weak prestimulus to transiently inhibit the response to a closely following strong sensory stimulus. This effect is reduced in a number of disorders known to be associated with impaired gating of sensory, cognitive or motor information. The aim of this study was to investigate PPI deficit in relation to the dimensions of auditory hallucinations in patients with schizophrenia or schizoaffective disorder.
  
  
  METHODS
  PPI of the acoustically elicited eye blink startle response was measured electromyographically in 62 patients with schizophrenia (n=55) or schizoaffective disorder (n=7) (26 of 62 with current auditory hallucinations) and 22 healthy participants matched, on average, to age and sex of the patient group.
  
  
  RESULTS
  Patients, as a group, showed reduced PPI compared to healthy participants. The presence of auditory hallucinations was associated with a marked PPI deficit if the patients felt that they had no control over their occurrence and that they were unable to dismiss them. Hearing voices with a high degree of negative content was associated with high mean startle amplitude in patients with current auditory hallucinations.
  
  
  CONCLUSIONS
  Although auditory hallucinations in patients with schizophrenia are theorised to result from impaired monitoring of inner speech, the inability to consciously ignore them appears to be associated with a gating deficit. Hearing voices with negative content is associated with hyper-startle responding, possibly because such voices are threatening and thus provoke anxiety.
authors.affiliation: Department of Psychology, Institute of Psychiatry, King's College London, London, UK. v.kumari@iop.kcl.ac.uk
authors.forename: Veena
authors.initials: V
authors.lastname: Kumari
authors.forename: Emmanuelle R
authors.initials: ER
authors.lastname: Peters
authors.forename: Dominic
authors.initials: D
authors.lastname: Fannon
authors.forename: Preethi
authors.initials: P
authors.lastname: Premkumar
authors.forename: Ingrid
authors.initials: I
authors.lastname: Aasen
authors.forename: Michael A
authors.initials: MA
authors.lastname: Cooke
authors.forename: Anantha P
authors.initials: AP
authors.lastname: Anilkumar
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kuipers
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001307:Auditory Perception; D001767:Blinking; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000209:etiology*; D011601:Psychophysics; D011930:Reaction Time; D013216:Reflex, Startle; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D013997:Time Factors; D014831:Voice / Q000502:physiology*