title: Entorhinal Cortex Volume in Antipsychotic-naïve Schizophrenia.
abstract: BACKGROUND
  Entorhinal cortex (ERC), a multimodal sensory relay station for the hippocampus, is critically involved in learning, emotion, and novelty detection. One of the pathogenetic mechanistic bases in schizophrenia is proposed to involve aberrant information processing in the ERC. Several studies have looked at cytoarchitectural and morphometric changes in the ERC, but results have been inconsistent possibly due to the potential confounding effects of antipsychotic treatment.
  
  
  METHODS
  In this study, we have examined the entorhinal cortex volume in antipsychotic-naïve schizophrenia patients (n=40; M:F=22:18) in comparison with age, sex, and handedness, matched (as a group) with healthy subjects (n=42; M:F=25:17) using a valid method. 3-Tesla MR images with 1-mm sections were used and the data was analyzed using the SPSS software.
  
  
  RESULTS
  Female schizophrenia patients (1.25±0.22 mL) showed significant volume deficit in the right ERC in comparison with female healthy controls (1.45±0.34 mL) (F=4.9; P=0.03), after controlling for the potential confounding effects of intracranial volume. However, male patients did not differ from male controls. The left ERC volume did not differ between patients and controls.
  
  
  CONCLUSIONS
  Consistent with the findings of a few earlier studies we found a reduction in the right ERC volume in patients. However, this was limited to women. Contextually, our study finding supports the role for ERC deficit in schizophrenia pathogenesis - perhaps mediated through aberrant novelty detection. Sex-differential observation of ERC volume deficit in schizophrenia needs further studies.
authors.affiliation: Department of Psychiatry, The Schizophrenia Clinic, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India.
authors.forename: Sam P
authors.initials: SP
authors.lastname: Jose
authors.forename: Eesha
authors.initials: E
authors.lastname: Sharma
authors.forename: Janardhanan C
authors.initials: JC
authors.lastname: Narayanaswamy
authors.forename: Vishnurajan
authors.initials: V
authors.lastname: Rajendran
authors.forename: Sunil V
authors.initials: SV
authors.lastname: Kalmady
authors.forename: Naren P
authors.initials: NP
authors.lastname: Rao
authors.forename: Ganesan
authors.initials: G
authors.lastname: Venkatasubramanian
authors.forename: Bangalore N
authors.initials: BN
authors.lastname: Gangadhar