Dorsolateral prefrontal cortex volume in patients with deficit or nondeficit schizophrenia

Deficit schizophrenia (DS) represents a promising putative clinical subtype of schizophrenia and is characterized by the presence of primary and enduring negative symptoms. Previous studies have often reported a reduced amount of gray matter within prefrontal and temporal cortices in schizophrenia subjects with prevailing negative symptoms; however, the evidence concerning brain structural abnormalities in patients with DS remains controversial.The aim of the present study was to investigate whether patients with DS differed from those with nondeficit schizophrenia (NDS) with respect to the volume of the dorsolateral prefrontal cortex (DLPFC) and hippocampus, two brain areas considered as key regions in the pathogenesis of schizophrenia.In the present study a 3D-T1w MR imaging procedure and an extensive clinical assessment was carried out in 18 patients with schizophrenia, (10 DS and 8 NDS). 3D MPRAGE images were preprocessed with SPM software and two regions of interest (hippocampus and DLPFC) were manually traced to obtain their gray matter volumes.We found a significant reduction of DLPFC in the entire schizophrenia group, with respect to healthy subjects. Although the subgroup of patients with DS had a more severe clinical picture and more impaired social functioning, the DLPFC volume reduction was greater in NDS than in DS patients.In conclusion, according to our structural neuroimaging findings, DS patients, although characterized by a more severe clinical picture and a worse outcome, show less neurobiological abnormalities.

► Subjects with deficit schizophrenia had a more severe clinical picture.
► Subjects with deficit schizophrenia had a less favorable functioning profile.
► A significant reduction of DLPFC was present in the whole schizophrenia group.
► Subjects with nondeficit schizophrenia had a greater volume reduction in DLPFC.
► Deficit schizophrenia is not simply the extreme end of a severity continuum.