Effect of treatment status on prepulse inhibition of acoustic startle in schizophrenia.
BACKGROUND
The acoustic startle response is inhibited when the startling stimulus is preceded by a weaker non-startling acoustic stimulus. This phenomenon, termed prepulse inhibition of acoustic startle (PPI), is impaired in schizophrenics compared to normal controls. To date, there is conflicting evidence regarding whether PPI impairments improve with antipsychotic treatment.


OBJECTIVE
To examine the effect of medication status on PPI in schizophrenic subjects.


METHODS
First, we performed acoustic startle testing on 16 schizophrenic subjects when they were acutely decompensated off medication and later after they were stabilized on antipsychotic treatment. Second, in a between-group design, we tested 21 schizophrenic subjects off medication, 16 subjects on atypical neuroleptics, and 27 subjects on typical neuroleptics.


RESULTS
In both the test-retest study and the between-group study, ANOVAs revealed no significant changes in startle to pulse alone stimuli, habituation of startle to pulse alone stimuli, PPI, latency to response onset, or latency to response peak between the treatment conditions.


CONCLUSIONS
Our results do not support the hypothesis that impaired sensorimotor gating in schizophrenia improves with antipsychotic treatment. Rather, impaired gating persists despite symptomatic improvement on medication.
Duncan
Erica J
EJ
Mental Health Service/116A, Atlanta Veterans Affairs Medical Center, 1670 Clairmont Road, Decatur, GA 30033, USA. erica.duncan2@med.va.gov
Szilagyi
Sandor
S
Efferen
Toby R
TR
Schwartz
Marion P
MP
Parwani
Arti
A
Chakravorty
Subhajit
S
Madonick
Steven H
SH
Kunzova
Alena
A
Harmon
James W
JW
Angrist
Burt
B
Gonzenbach
Stephen
S
Rotrosen
John P
JP
D000161:Acoustic Stimulation; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D006185:Habituation, Psychophysiologic; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time; D013216:Reflex, Startle / Q000187:drug effects*; D012559:Schizophrenia / Q000188:drug therapy*; D012565:Schizophrenic Psychology
D014150:Antipsychotic Agents