title: Correlation between prepulse inhibition and cortical perfusion during an attentional test in schizophrenia. A pilot study.
abstract: BACKGROUND
  Processes underlying cortical hypoactivation in schizophrenia are poorly understood but some evidence suggests that a deficient sensory filtering is associated with the condition. This filtering deficit can be studied by using measures of prepulse inhibition (PPI) of the startle reflex.
  
  
  OBJECTIVE
  To evaluate the contribution of sensory filtering deficits to cortical hypoperfusion during an attention test in schizophrenia.
  
  
  METHODS
  Measurements of PPI of the startle reflex and perfusion during the performance of a Stroop test (assessed with single photon emission tomography) were obtained in 10 acutely treated schizophrenia patients (6 with recent onset, RO) and 16 control subjects. These measurements were compared between patients and controls and the correlation between PPI and perfusion was evaluated within each group, using Statistical Parametric Mapping.
  
  
  RESULTS
  In comparison with normal subjects, the patients exhibited lower PPI, although the difference was not statistically significant. Perfusion was significantly lower in the prefrontal and premotor regions of the patients. In the patient group, a statistically significant difference was observed between PPI and perfusion in the parietal, premotor, and cingulate regions. When the associations were analyzed in the RO patients alone, a positive correlation was also found between prefrontal perfusion and PPI, while anterior hippocampal perfusion was inversely related to PPI.
  
  
  CONCLUSIONS
  These results support the notion that deficient sensory-motor filtering is associated with decreased cortical task-related activation in schizophrenia.
authors.affiliation: Department of Psychiatry, Hospital Clínico Universitario, Institute for Neuroscience of Castilla y León, Universidad de Salamanca, Salamanca, Spain. vmolina@usal.es
authors.forename: V
authors.initials: V
authors.lastname: Molina
authors.forename: C
authors.initials: C
authors.lastname: Montes
authors.forename: P
authors.initials: P
authors.lastname: Tamayo
authors.forename: R
authors.initials: R
authors.lastname: Villa
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Osuna
authors.forename: J
authors.initials: J
authors.lastname: Pérez
authors.forename: C
authors.initials: C
authors.lastname: Sancho
authors.forename: T
authors.initials: T
authors.lastname: López-Albuquerque
authors.forename: A
authors.initials: A
authors.lastname: Cardoso
authors.forename: O
authors.initials: O
authors.lastname: Castellano
authors.forename: D E
authors.initials: DE
authors.lastname: López
mesh_terms: D000328:Adult; D001288:Attention; D002540:Cerebral Cortex / Q000098:blood supply* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011597:Psychomotor Performance; D013216:Reflex, Startle / Q000502:physiology*; D012563:Schizophrenia, Paranoid / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D055139:Sensory Gating; D015899:Tomography, Emission-Computed, Single-Photon