No abstract

Deficits in episodic memory, related to medial temporal lobe dysfunction, are a core component of schizophrenia. Rey's Auditory Verbal Learning Test (RAVLT) is one of the most widely used neuropsychological memory tasks in clinical practice but normative data are limited. Over the last 15 years, the RAVLT has been used to assess verbal episodic memory performance as part of the Western Australian Family Study of Schizophrenia (WAFSS). This study aims to provide RAVLT norms, derived from the WAFSS, for individuals meeting DSM-IV and ICD-10 diagnostic criteria for schizophrenia or schizophrenia-spectrum disorder, for use in clinical settings. Performance on three immediate and one delayed recall trials, and additional measures of encoding and forgetting, is presented for 492 patients and 260 healthy community controls. Results indicated that age and sex (both groups) and IQ (schizophrenia group only) significantly influenced performance. Norms are presented, as means and standard deviations, stratified accordingly. Additional between-groups analysis clearly shows a significant memory deficit in schizophrenia even when patients are matched on IQ, age, and sex with healthy controls.

Impairments in executive function and cognitive control are a common feature of neuropsychiatric and neurodegenerative disorders. A promising behavioral paradigm for elucidating the neural mechanisms of executive function is extradimensional/intradimensional (ED/ID) shifting, which places demands on executive function by requiring the adjustment of behavioral responses based on affective or attentional information. To augment the understanding of the brain systems required for these aspects of executive function, we examined the induction of Fos protein in rats tested in the ED/ID paradigm. We found increased Fos-like immunoreactivity (Fos-LI) in several cortical areas, including medial and orbital frontal cortex (OFC), in rats performing affective or attentional shifts relative to rats performing control discriminations. However, increased Fos-LI was also present in rats that performed a yoked number of additional control discrimination trials, without affective or attentional shifting. These observations suggest that cortical networks required for affective and attentional shifting are also activated during comparable discrimination tasks that do not require shifting, consistent with a role for these networks in monitoring ongoing behavior even in situations in which adaptation to changing behavioral demands is not required.