Time filter

Source Type

Keating C.,Monash Alfred Psychiatry Research Center rc
Current Topics in Behavioral Neurosciences | Year: 2011

In anorexia nervosa (AN), reward contamination likely plays a significant role in maintenance of the illness. Reward contamination is a context in which patients' behaviors of self-starvation and excessive exercise, while initially rewarding, become aversive, even punishing; but patients may not recognize the punishing and conflicted/contaminated behaviors. An emerging neurocircuit encompassing the anterior cingulate cortex (ACC) has been functionally linked to symptoms including reward contamination and body dysmorphic processing. Owing to the significantly greater prevalence of AN in females, evidence from clinical literature and preclinical models is spearheaded to provide a novel rationale for estrogen triggering sensitivity to the experience of stress and reward, precipitating AN disproportionately in females at the time of puberty. Paradoxically, however, estrogen may facilitate response to pharmacological interventions and (desensitization of the identified neurocircuits) via its contribution to serotonin modulation, hypothalamo-pituitary adrenal (HPA)-axis attenuation, and effects on dopamine. © Springer-Verlag Berlin Heidelberg 2011. Source

Van Rheenen T.E.,Swinburne University of Technology | Van Rheenen T.E.,Monash University | Van Rheenen T.E.,Monash Alfred Psychiatry Research Center rc | Rossell S.L.,Swinburne University of Technology | Rossell S.L.,Monash University
Journal of Affective Disorders | Year: 2014

Background People with bipolar disorder (BD) experience significant psychosocial impairment. Understandings of the nature and causes of such impairment is limited by the lack of research exploring the extent to which subjectively reported functioning should be valued as an indicator of objective dysfunction, or examining the relative influence of neurocognition, social cognition and emotion regulation on these important, but different aspects of psychosocial functioning in the context of mania and depression symptoms. This study aimed to address this paucity of research by conducting a comprehensive investigation of psychosocial functioning in a well characterised group of BD patients. Methods Fifty-one BD patients were compared to 52 healthy controls on objectively and subjectively assessed psychosocial outcomes. Relationships between current mood symptoms, psychosocial function and neurocognitive, social cognitive and emotion regulation measures were also examined in the patient group. Results Patients had significantly worse scores on the global objective and subjective functioning measures relative to controls. In the patient group, although these scores were correlated, regression analyses showed that variance in each of the measures was explained by different predictors. Depressive symptomatology was the most important predictor of global subjective functioning, and neurocognition had a concurrent and important influence with depressive symptoms on objective psychosocial function. Emotion regulation also had an indirect effect on psychosocial functioning via its influence on depressive symptomatology. Limitations As this study was cross-sectional in nature, we are unable to draw precise conclusions regarding contributing pathways involved in psychosocial functioning in BD. Conclusions These results suggest that patients' own evaluations of their subjective functioning represent important indicators of the extent to which their observable function is impaired. They also highlight the importance of incorporating cognitive and emotion regulation assessments into clinical practice when working to reduce psychosocial dysfunction with patients diagnosed with BD. © 2014 Elsevier B.V. All rights reserved. Source

Andrews S.C.,Monash University | Hoy K.E.,Monash University | Enticott P.G.,Monash University | Daskalakis Z.J.,University of Toronto | And 2 more authors.
Brain Stimulation | Year: 2011

Background: Transcranial direct current stimulation (tDCS), applied to the left dorsolateral prefrontal cortex (DLPFC) has been found to improve working memory (WM) performance in both healthy and clinical participants. However, whether this effect can be enhanced by cognitive activity undertaken during tDCS has not yet been explored. Objective: This study aimed to explore whether tDCS applied to the left DLPFC during the persistent performance of one WM task would improve performance on a subsequent WM task, to a greater extent than either tDCS or cognitive activity alone. Methods: Ten healthy participants took part in three counterbalanced conditions. The conditions involved 10 minutes of either anodal tDCS while completing an n-back task, anodal tDCS while at rest, or sham tDCS while completing an n-back task. The n-back that was used in this study was a computer-based letter WM task that involved 5 minutes of two-back, followed by 5 minutes of three-back. Digit span forward and backward was administered immediately before and after each treatment, and performance change (pre- to posttreatment) calculated and compared across conditions. The digit span tasks involved a series of numbers being read to the participant, and the participant was required to repeat them back, either in the same order (Digits forward) or in the reverse order (Digits backward). Results: tDCS applied during completion of the n-back task was found to result in greater improvement in performance on digit span forward, compared with tDCS applied while at rest and sham tDCS during the n-back task. This finding was not evident with digit span backward. Conclusions: These results indicate that there may be potential for the use of adjunctive cognitive remediation techniques to enhance the effects of tDCS. However, further research needs to be undertaken in this area to replicate and extend this finding. © 2011 Elsevier Inc. Source

Van Rheenen T.E.,Swinburne University of Technology | Van Rheenen T.E.,Monash Alfred Psychiatry Research Center rc | Rossell S.L.,Swinburne University of Technology | Rossell S.L.,Monash Alfred Psychiatry Research Center rc
Journal of the International Neuropsychological Society | Year: 2014

The ability to integrate information from different sensory channels is a vital process that serves to facilitate perceptual decoding in times of unimodal ambiguity. Despite its relevance to psychosocial functioning, multimodal integration of emotional information across facial and prosodic modes has not been addressed in bipolar disorder (BD). In light of this paucity of research we investigated multimodal processing in a BD cohort using a focused attention paradigm. Fifty BD patients and 52 healthy controls completed a task assessing the cross-modal influence of emotional prosody on facial emotion recognition across congruent and incongruent facial and prosodic conditions, where attention was directed to the facial channel. There were no differences in multi-modal integration between groups at the level of accuracy, but differences were evident at the level of response time; emotional prosody biased facial recognition latencies in the control group only, where a fourfold increase in response times was evident between congruent and incongruent conditions relative to patients. The results of this study indicate that the automatic process of integrating multimodal information from facial and prosodic sensory channels is delayed in BD. Given that interpersonal communication usually occurs in real time, these results have implications for social functioning in the disorder. Copyright © INS.Published by Cambridge University Press, 2014. Source

Van Rheenen T.E.,Swinburne University of Technology | Van Rheenen T.E.,Monash Alfred Psychiatry Research Center rc | Rossell S.L.,Swinburne University of Technology | Rossell S.L.,Monash Alfred Psychiatry Research Center rc
Journal of Affective Disorders | Year: 2013

Background This paper reports the performance of DSM-IV-TR diagnosed bipolar disorder (BD) patients on a well-recognised measure of theory of mind (ToM) that commonly elicits group-related differences in schizophrenia research. Methods Forty-nine BD patients and 49 age and gender matched controls completed Langdon and Coltheart (1999) Picture Sequencing Task. Results Relative to controls, patients with BD performed significantly worse on the ToM relevant false-belief stories of the picture sequencing task, but not on the control stories requiring social script knowledge, executive control or an understanding of causal connexions. There were no differences in the ToM performance of symptomatic versus euthymic patients or those categorised as having BD I or BD II. Limitations As sub group sizes were small, data suggesting a trait-like deficit in ToM should be interpreted with caution. Conclusions The results support previous evidence of ToM impairment in BD and indicate a potential endophenotypic overlap in the phenomenology of both schizophrenia and BD. © 2013 Elsevier B.V. Source

Discover hidden collaborations