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Aims Bipolar disorder is characterized by progressive changes in cognition with declines in executive functioning, memory and sustained attention. Current pharmacotherapies for bipolar disorder target mood symptoms but have not addressed these cognitive changes resulting in euthymic individuals who still experience cognitive deficits. N-acetyl cysteine ( NAC) has been shown to have effects on antioxidant status, glutamate transmission, inflammation and neurogenesis. Adjunctive treatment with NAC improves the symptoms experienced by those with bipolar disorder, particularly depression, and it was hypothesized that cognition may also be improved following NAC treatment. Methods As part of a larger randomized, double-blind, placebo-controlled trial, participants in the current report were tested at baseline and 6 months to assess changes in cognitive function following either 2000 mg of NAC daily or placebo. Results This study failed to find changes in cognitive function following treatment with NAC compared to placebo. Conclusions While an important pilot study, this study had a small sample size and included a limited battery of cognitive tests. Further investigations on the effects of NAC on cognitive performance in bipolar disorder are required. [ABSTRACT FROM AUTHOR]

A significant proportion of subjects drop out of medium to long-term clinical studies prior to trial completion. This may bias reported study outcomes and reduce the statistical power of analyses. There is therefore a need for researchers to better understand the characteristics of dropout populations to increase completion rates. Data from a set of participants recruited as part of a 24-week placebo-controlled trial were used to determine the relationship between the five Lindenmayer factors of positive, negative, cognitive, anxiety/depression and excitement symptoms and dropout at trial completion. Results indicated that the rate of trial dropout was significantly predicted by scores on the negative Lindenmayer factor ( X2(6, N = 126) = 15.60, p < .05). By trial completion, participants with 'high' negative Lindenmayer scores dropped out at a rate of 64%, whereas 'medium' and 'low' groups dropped out at 43% and 30%, respectively. No other relationship between symptom severity scores and dropout across the remaining Lindenmayer factors was found. These findings reflect important considerations for the future design of clinical trials involving people with schizophrenia and may also provide clues into treatment compliance issues more generally. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A number of techniques have been used to provide functional connectivity estimates for a given fMRI data set. In this study we compared two methods: a 'rest-like' method where the functional connectivity was estimated for the whitened residuals after regressing out the task-induced effects, and a within-condition method where the functional connectivity was estimated separately for each experimental condition. In both cases four pre-processing strategies were used: 1) time courses extracted from standard pre-processed data (standard); 2) adjusted time courses extracted using the volume of interest routines in SPM2 from standard pre-processed data (spm); 3) time courses extracted from ICA denoised data (standard denoised); and 4) adjusted time courses extracted from ICA denoised data (spm denoised). The temporal correlation between time series extracted from two cortical regions were statistically compared with the temporal correlation between a time series extracted from a cortical region and a time series extracted form a region placed in CSF. Since the later correlation is due to physiological noise and other artifacts, we used this comparison to investigate whether rest-like and task modulated connectivity could be estimated from the same data set. The pre-processing strategy had a significant effect on the connectivity estimates with the standard time courses providing larger connectivity values than the spm time courses for both estimation methods. The CSF comparison indicated that for our data set only rest-like connectivity could be estimated. The rest-like connectivity values were similar with connectivity estimated from resting state data. Hum Brain Mapp 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Acceptance and mindfulness methods that emphasise the acceptance rather than control of symptoms are becoming more central to behavioural and cognitive therapies. Acceptance and Commitment Therapy (ACT) is the most developed of these methods; recent applications of ACT to psychosis suggest it to be a promising therapeutic approach. However, investigation of the mechanisms of therapy within this domain is difficult because there are no acceptance-based measures available specifically for psychotic symptoms. This paper describes the preliminary evaluation of a self-report instrument designed to assess acceptance-based attitudes and actions in relation to auditory and command hallucinations. Following initial scale development, a 56-item version of the Voices Acceptance and Action Scale (VAAS) was administered to 43 participants with command hallucinations as part of their baseline assessment in a larger trial. Measures of symptoms, quality of life, and depression were also administered. The scale was examined for reliability using corrected item total statistics. Based on this method, 31 items were retained. Internal consistency and test-retest reliability for the 31-item VAAS were acceptable. Subsequent examination of construct validity showed the VAAS to correlate significantly in the expected directions with depression, quality of life, and coping with command hallucinations. It also discriminated compliance from non-compliance with harmful command hallucinations. Although these results are preliminary and subject to a number of limitations, the VAAS shows promise as a useful aid in the assessment of the psychological impact of voices. © 2007 Wiley Periodicals, Inc. J Clin Psychol. [ABSTRACT FROM AUTHOR]

Abstract: Having shown a decrease in serotonin2A receptors in the dorsolateral prefrontal cortex (DLPFC) from schizophrenic subjects, we have now determined if this change was reflective of widespread changes in neurochemical markers in DLPFC in schizophrenia. In Brodmann’s area (BA) 9 from 19 schizophrenic and 19 control subjects, we confirmed a decrease in the density of [3H]ketanserin binding to serotonin2A receptors in tissue from the schizophrenic subjects [39 ± 3.3 vs. 60 ± 3.6 fmol/mg estimated tissue equivalents (ETE); p < 0.005]. In addition, the density of [3H]muscimol binding to GABAA receptors was increased in the schizophrenic subjects (526 ± 19 vs. 444 ± 28 fmol/mg ETE; p < 0.02). [3H]YM-09151-2, N-[1-(2-thienyl)cyclohexyl]-3,4-[3H]piperidine, [3H]SCH 23390, [3H]mazindol, and NG-nitro-L-[3H]arginine binding to BA 9 did not differ between groups, and there was no specific binding of [3H]raclopride or 7-hydroxy-2-(di-n-[3H]propylamino)tetralin to BA 9 from either cohort of subjects. This suggests the density of dopamine D1-like and NMDA receptors, the dopamine transporter, and nitric oxide synthase activity are not altered in BA 9 from schizophrenic subjects. The selective nature of the changes in serotonin2A and GABAA receptors in DLPFC could indicate that these changes are involved in the pathology of schizophrenia. [ABSTRACT FROM AUTHOR]