A Comparison of Serial Position Effects in Patients with Mild Cognitive Impairment due to Parkinson's Disease or to Alzheimer's Disease.

OBJECTIVE: The first (primacy region) and last (recency region) items of a word list are generally better memorized than items from the middle region. The recency effect depends on short-term memory (STM) and the primacy effect on long-term memory (LTM), where verbal information is transferred from STM into LTM by maintenance rehearsal. We compared the serial position effects (SPE) between patients with mild cognitive impairment (MCI) due to Parkinson's disease (PD), i.e., PD-MCI, and patients with MCI due to Alzheimer's disease (AD-MCI), and evaluated the influence of SPE and frontostriatal deficits on verbal memory recall. METHODS: Four similar groups of subjects participated in the study: 26 PD-MCI patients, 26 cognitively normal patients with PD (PD-CN), 26 AD-MCI patients, and 26 normal controls (NC). Verbal episodic memory, verbal span, attentional capacity, executive functions, and verbal working memory performance were assessed. Measures for primacy and recency regions were defined at the first trial of a 16-items word list. Hierarchical regression models were used to investigate the contribution of frontostriatal deficits beyond SPE on verbal memory recall performance ("long-delay free recall") in PD and AD patients. RESULTS: Primacy effects were significantly diminished in both PD-MCI and AD-MCI patients relative to NC and PD-CN (all p < 0.01). Compared to PD-MCI patients, AD-MCI patients exhibited significantly worse "delayed-recall 'savings'." Reduced primacy effect was predictive for decreased recall performance in PD and AD. The conducted hierarchical regression model revealed that in PD, but not in AD patients, performance of attention and executive function significantly increased the prediction of free recalled words. CONCLUSIONS: Reduced recall performance is likely due to impaired transition of newly learned material from STM into LTM in AD and in PD. Whereas AD-MCI patients suffer from a storage deficit, the similarly reduced recall performance found in patients with PD-MCI may additionally be related to deficient attentional and executive capacity.

Structural Magnetic Resonance Imaging Correlates of Aggression in Psychosis: A Systematic Review and Effect Size Analysis.

Background: Aggression in psychoses is of high clinical importance, and volumetric MRI techniques have been used to explore its structural brain correlates. Methods: We conducted a systematic review searching EMBASE, ScienceDirect, and PsycINFO through September 2017 using thesauri representing aggression, psychosis, and brain imaging. We calculated effect sizes for each study and mean Hedge's g for whole brain (WB) volume. Methodological quality was established using the PRISMA checklist (PROSPERO: CRD42014014461). Results: Our sample consisted of 12 studies with 470 patients and 155 healthy controls (HC). After subtracting subjects due to cohort overlaps, 314 patients and 96 HC remained. Qualitative analyses showed lower volumes of WB, prefrontal regions, temporal lobe, hippocampus, thalamus and cerebellum, and higher volumes of lateral ventricles, amygdala, and putamen in violent vs. non-violent people with schizophrenia. In quantitative analyses, violent persons with schizophrenia exhibited a significantly lower WB volume than HC (p = 0.004), and also lower than non-violent persons with schizophrenia (p = 0.007). Conclusions: We reviewed evidence for differences in brain volume correlates of aggression in persons with schizophrenia. Our results point toward a reduced whole brain volume in violent as opposed to non-violent persons with schizophrenia. However, considerable sample overlap in the literature, lack of reporting of potential confounding variables, and missing research on affective psychoses limit our explanatory power. To permit stronger conclusions, further studies evaluating structural correlates of aggression in psychotic disorders are needed.

Prediction of caseness for mental pathology in Swiss conscripts: the Self-Screen Prodrome.

BACKGROUND: Basic military training (BMT) is an environment of higher stress levels than are encountered in civilian life. It may trigger mental disorders in predisposed individuals. To reduce BMT attrition because of mental problems a psychiatric assessment is part of the Swiss recruitment process. An initial screening survey that identifies vulnerable individuals will be useful to save both cost and effort when dealing with large populations, such as military draftees. Aims of this investigation are to verify the psychometric properties of the Self-Screen Prodrome (SPro), a newly developed, short screening tool for psychopathology, and to validate it against the Symptom Checklist-90-Revised (SCL-90-R), a well-established self-assessment instrument. METHOD: A sample of 12,380 male conscripts from the year 2003 were administered both the SPro and the SCL-90-R. Vulnerability was operationalized using the "caseness" definition of the SCL-90-R. RESULTS: Factor analysis demonstrated unidimensional scaling of the SPro, and this was supported by high internal reliability. Scores of nine or more symptoms on the SPro scale were found to successfully discriminate between SCL-90-R positive and negative cases. It is thus an adequate measure of general psychopathology (caseness). The association of p = 0.77 between the SPro and the SCL-90-R Global Severity Index (GSI) clearly supports concurrent validity. Our data also demonstrated that the SPro can distinguish individuals with self-reported mental health problems from those with no or few reported symptoms (cutoff > or = 9; sensitivity 89.3%; specificity 84.9%; AUC 0.942; CI 95% 0.935-0.948). CONCLUSION: Though replication and further research are needed, the SPro scale may currently be a useful screening tool for initial screening in a two-stage process of early detection of psychopathology.