Cortical grey matter volume and sensorimotor gating in schizophrenia

Cortex. 2008 Oct;44(9):1206-14. doi: 10.1016/j.cortex.2007.11.007. Epub 2008 Jan 20.

Abstract

Prepulse inhibition (PPI) of the startle response, a cross-species measure of sensorimotor gating, provides a valuable tool to study the known inability of a large proportion of individuals with schizophrenia to effectively screen out irrelevant sensory input. The cortico-striato-pallido-thalamic circuitry is thought to be responsible for modulation of PPI in experimental animals. The involvement of this circuitry in human PPI is supported by observations of deficient PPI in a number of neuropsychiatric disorders that are characterised by abnormalities at some level in this circuitry, and findings of recent functional neuroimaging studies in healthy participants. The current study sought to investigate the structural neural correlates of PPI in a sample of 42 stable male outpatients with schizophrenia. Participants underwent magnetic resonance imaging (MRI) at 1.5T and were assessed (off-line) on acoustic PPI using electromyographic recordings of the orbicularis oculi muscle beneath the right eye. Optimised volumetric voxel-based morphometry implemented in SPM2 was used to investigate the relationship of PPI (prepulse onset-to-pulse onset interval 120msec) to regional grey matter (GM) volumes. Significant positive correlations were obtained between PPI and GM volume in the dorsolateral prefrontal, middle frontal and the orbital/medial prefrontal cortices. Our findings are consistent with (a) previous suggestions of susceptibility of PPI to cognitive processes controlled in a 'top down' manner by the cortex and (b) the hypothesis that compromised neural resources in the frontal cortex contribute to reduced PPI in schizophrenia.

Publication types

  • Clinical Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acoustic Stimulation / methods
  • Adult
  • Blinking / physiology
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiopathology*
  • Dominance, Cerebral / physiology
  • Electromyography / methods
  • Facial Muscles / physiology
  • Frontal Lobe / pathology
  • Frontal Lobe / physiopathology
  • Habituation, Psychophysiologic / physiology*
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Prefrontal Cortex / pathology
  • Prefrontal Cortex / physiopathology
  • Reaction Time / physiology
  • Reflex, Startle / physiology*
  • Schizophrenia / physiopathology*
  • Statistics as Topic