ANTERIOR HIPPOCAMPAL VOLUME REDUCTIONS PREDICT FRONTAL-LOBE DYSFUNCTION IN FIRST EPISODE SCHIZOPHRENIA

This study examined relations of mesiotemporal lobe tissue volumes wit h neuropsychological (NP) functions in a sample of patients with first episode schizophrenia. Three contiguous compartments of the mesiotemp oral lobe were measured on magnetic resonance images, comprising prima rily amygdaloid, anterior hippocampal, and posterior hippocampal tissu e volumes. NP measures were derived from a comprehensive battery. Decr eased volume selectively in the anterior hippocampal formation was ass ociated with lower scores on measures of executive and motor functions usually considered sensitive to the integrity of frontal lobe systems . Measures of other NP functions, and global intellectual ability, wer e not related to mesiotemporal volumes. The findings that morphologic abnormalities in the mesiotemporal lobe are associated with impairment of frontal lobe functions point to a defect in an integrated function al system that includes both frontal and mesiotemporal components. The findings are consistent with the hypothesis that neurodevelopmental d efects affecting the morphology of the anterior hippocampal formation may be manifest later in life as impairments in fronto-limbic control. </p>