Melbourne School of Psychological Sciences - Research Publications

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    Learning from Errors: Error-Related Neural Activity Predicts Improvements in Future Inhibitory Control Performance
    Hester, R ; Madeley, J ; Murphy, K ; Mattingley, JB (SOC NEUROSCIENCE, 2009-06-03)
    Failure to adapt performance following an error is a debilitating symptom of many neurological and psychiatric conditions. Healthy individuals readily adapt their behavior in response to an error, an ability thought to be subserved by the posterior medial frontal cortex (pMFC). However, it remains unclear how humans adaptively alter cognitive control behavior when they reencounter situations that were previously failed minutes or days ago. Using functional magnetic resonance imaging, we examined neural activity during a Go/No-go response inhibition task that provided the opportunity for participants to learn from their errors. When they failed to inhibit their response, they were shown the same target stimulus during the next No-go trial, which itself could occur up to 20 trials after its initial presentation. Activity within the pMFC was significantly greater for initial errors that were subsequently corrected than for errors that were repeated later in the display sequence. Moreover, pMFC activity during errors predicted future responses despite a sizeable interval (on average 12 trials) between an error and the next No-go stimulus. Our results indicate that changes in cognitive control performance can be predicted using error-related activity. The increased likelihood of adaptive changes occurring during periods of recent success is consistent with models of error-related activity that argue for the influence of outcome expectancy (Holroyd and Coles, 2002; Brown and Braver, 2005). The findings may also help to explain the diminished error-related neural activity in such clinical conditions as schizophrenia, as well as the propensity for perseverative behavior in these clinical groups.
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    Transforming Disability: Music in Special Education
    Farrell, H (Australian Society for Music Education, 2009)
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    Impaired Error Awareness and Anterior Cingulate Cortex Hypoactivity in Chronic Cannabis Users
    Hester, R ; Nestor, L ; Garavan, H (NATURE PUBLISHING GROUP, 2009-10)
    Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing. A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior. A total of 16 active chronic cannabis users and 16 control participants were administered a Go/No-go response inhibition task during event-related fMRI data collection. The task provides measures of inhibitory control and error awareness. Cannabis users' inhibitory control performance was equivalent to that of the control group, but the former showed a significant deficit in awareness of commission errors. Cannabis users showed a diminished capacity for monitoring their behavior that was associated with hypoactivity in the ACC and right insula. In addition, increased levels of hypoactivity in both the ACC and right insula regions were significantly correlated with error-awareness rates in the cannabis group (but not controls). These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.
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    Central Nervous System Function in Youth With Type 1 Diabetes 12 Years After Disease Onset
    Northam, EA ; Rankins, D ; Lin, A ; Wellard, RM ; Pell, GS ; Finch, SJ ; Werther, GA ; Cameron, FJ (AMER DIABETES ASSOC, 2009-03)
    OBJECTIVE: In this study, we used neurocognitive assessment and neuroimaging to examine brain function in youth with type 1 diabetes studied prospectively from diagnosis. RESEARCH DESIGN AND METHODS: We studied type 1 diabetic (n = 106) and control subjects (n = 75) with no significant group difference on IQ at baseline 12 years previously by using the Wechsler Abbreviated Scale of General Intelligence, magnetic resonance spectroscopy and imaging, and metabolic control data from diagnosis. RESULTS: Type 1 diabetic subjects had lower verbal and full scale IQs than control subjects (both P < 0.05). Type 1 diabetic subjects had lower N-acetylaspartate in frontal lobes and basal ganglia and higher myoinositol and choline in frontal and temporal lobes and basal ganglia than control subjects (all P < 0.05). Type 1 diabetic subjects, relative to control subjects, had decreased gray matter in bilateral thalami and right parahippocampal gyrus and insular cortex. White matter was decreased in bilateral parahippocampi, left temporal lobe, and middle frontal area (all P < 0.0005 uncorrected). T2 in type 1 diabetic subjects was increased in left superior temporal gyrus and decreased in bilateral lentiform nuclei, caudate nuclei and thalami, and right insular area (all P < 0.0005 uncorrected). Early-onset disease predicted lower performance IQ, and hypoglycemia was associated with lower verbal IQ and volume reduction in thalamus; poor metabolic control predicted elevated myoinositol and decreased T2 in thalamus; and older age predicted volume loss and T2 change in basal ganglia. CONCLUSIONS: This study documents brain effects 12 years after diagnosis in a type 1 diabetic sample whose IQ at diagnosis matched that of control subjects. Findings suggest several neuropathological processes including gliosis, demyelination, and altered osmolarity.
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    Assessing knowledge of human papillomavirus and collecting data on sexual behavior: computer assisted telephone versus face to face interviews
    Smith, A ; Lyons, A ; Pitts, M ; Croy, S ; Ryall, R ; Garland, S ; Wong, ML ; Tay, EH (BMC, 2009-11-23)
    BACKGROUND: Education campaigns seeking to raise awareness of human papillomavirus (HPV) and promoting HPV vaccination depend on accurate surveys of public awareness and knowledge of HPV and related sexual behavior. However, the most recent population-based studies have relied largely on computer-assisted telephone interviews (CATI) as opposed to face to face interviews (FTFI). It is currently unknown how these survey modes differ, and in particular whether they attract similar demographics and therefore lead to similar overall findings. METHODS: A comprehensive survey of HPV awareness and knowledge, including sexual behavior, was conducted among 3,045 Singaporean men and women, half of whom participated via CATI, the other half via FTFI. RESULTS: Overall levels of awareness and knowledge of HPV differed between CATI and FTFI, attributable in part to demographic variations between these survey modes. Although disclosure of sexual behavior was greater when using CATI, few differences between survey modes were found in the actual information disclosed. CONCLUSION: Although CATI is a cheaper, faster alternative to FTFI and people appear more willing to provide information about sexual behavior when surveyed using CATI, thorough assessments of HPV awareness and knowledge depend on multiple survey modes.
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    Study protocol: the development of a randomised controlled trial testing a postcard intervention designed to reduce suicide risk among young help-seekers
    Robinson, J ; Hetrick, S ; Gook, S ; Cosgrave, E ; Yuen, HP ; McGorry, P ; Yung, A (BMC, 2009-09-23)
    BACKGROUND: Suicidal behaviour and deliberate self harm are common among adolescents. Limited evidence exists regarding interventions that can reduce risk; however research indicates that maintaining contact either via letter or postcard with at-risk adults following discharge from services can reduce risk. The aim of the study is to test a postcard intervention among people aged 15-24 who presented to mental health services but are not accepted, yet are at risk of suicide. METHODS/DESIGN: The study is a 3-year randomised controlled trial conducted at Orygen Youth Health Research Centre in Melbourne Australia. Participants are young help-seekers aged 15-24 who are at risk of suicide. Participants will be recruited over a 12 month period. The intervention comprises a regular postcard to be sent monthly for 12 months. The postcard enquires after their well being and includes information regarding individual sources of help and evidence-based self help strategies. Participants are assessed at baseline, 12 and 18 months. DISCUSSION: This paper describes the development of a study which aims to reduce suicide risk in a sample of young help-seekers. If effective, this intervention could have significant clinical and research implications for a population who can be hard to treat and difficult to research. TRIAL REGISTRATION: The study was registered with the Australian Clinical Trials Registry; number: ACTRN012606000274572.
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    Spatial Representations Are Specific to Different Domains of Knowledge
    Beecham, R ; Reeve, RA ; Wilson, SJ ; Antonietti, A (PUBLIC LIBRARY SCIENCE, 2009-05-20)
    There is evidence that many abstract concepts are represented cognitively in a spatial format. However, it is unknown whether similar spatial processes are employed in different knowledge domains, or whether individuals exhibit similar spatial profiles within and across domains. This research investigated similarities in spatial representation in two knowledge domains--mathematics and music. Sixty-one adults completed analogous number magnitude and pitch discrimination tasks: the Spatial-Numerical Association of Response Codes and Spatial-Musical Association of Response Codes tasks. Subgroups of individuals with different response patterns were identified through cluster analyses. For both the mathematical and musical tasks, approximately half of the participants showed the expected spatial judgment effect when explicitly cued to focus on the spatial properties of the stimuli. Despite this, performances on the two tasks were largely independent. Consistent with previous research, the study provides evidence for the spatial representation of number and pitch in the majority of individuals. However, there was little evidence to support the claim that the same spatial representation processes underpin mathematical and musical judgments.
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    The Neurocognitive Components of Pitch Processing: Insights from Absolute Pitch
    Wilson, SJ ; Lusher, D ; Wan, CY ; Dudgeon, P ; Reutens, DC (OXFORD UNIV PRESS INC, 2009-03)
    The natural variability of pitch naming ability in the population (known as absolute pitch or AP) provides an ideal method for investigating individual differences in pitch processing and auditory knowledge formation and representation. We have demonstrated the involvement of different cognitive processes in AP ability that reflects varying skill expertise in the presence of similar early age of onset of music tuition. These processes were related to different regions of brain activity, including those involved in pitch working memory (right prefrontal cortex) and the long-term representation of pitch (superior temporal gyrus). They reflected expertise through the use of context dependent pitch cues and the level of automaticity of pitch naming. They impart functional significance to structural asymmetry differences in the planum temporale of musicians and establish a neurobiological basis for an AP template. More generally, they indicate variability of knowledge representation in the presence of environmental fostering of early cognitive development that translates to differences in cognitive ability.
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    Reported awareness of tobacco advertising and promotion in China compared to Thailand, Australia and the USA.
    Li, L ; Yong, H-H ; Borland, R ; Fong, GT ; Thompson, ME ; Jiang, Y ; Yang, Y ; Sirirassamee, B ; Hastings, G ; Harris, F (BMJ Publishing Group, 2009-06)
    BACKGROUND: China currently does not have comprehensive laws or regulations on tobacco advertising and promotion, although it ratified the World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC) in October 2005 and promised to ban all tobacco advertising by January 2011. Much effort is needed to monitor the current situation of tobacco advertising and promotion in China. OBJECTIVE: This study aims to examine levels of awareness of tobacco advertising and promotion among smokers in China as compared to other countries with different levels of restrictions. METHODS: One developing country (Thailand) and two developed countries (Australia and the USA) were selected for comparison. All four countries are part of the International Tobacco Control (ITC) Policy Evaluation Survey project. Between 2005 and 2006, parallel ITC surveys were conducted among adult smokers (at least smoked weekly) in China (n = 4763), Thailand (n = 2000), Australia (n = 1767) and the USA (n = 1780). Unprompted and prompted recall of noticing tobacco advertising and promotion were measured. RESULTS: Chinese respondents reported noticing tobacco advertisements in a range of channels and venues, with highest exposure levels on television (34.5%), billboards (33.4%) and in stores (29.2%). A quarter of respondents noticed tobacco sponsorships, and a high level of awareness of promotion was reported. Cross-country comparison reveals that overall reported awareness was significantly higher in China than in Thailand (particularly) and Australia, but lower than in the USA. CONCLUSIONS: There is a big gap between China and the better-performing countries such as Thailand and Australia regarding tobacco promotion restrictions. China needs to do more, including enhanced policy and more robust enforcement.
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    Using latent variables to account for heterogeneity in exponential family random graph models
    Koskinen, J ; Ermakov, SM ; Melas, V ; Pepelyshev, AN (Saint Petersburg State University, 2009)
    We consider relaxing the homogeneity assumption in exponential family random graph models (ERGMs) using binary latent class indicators. This may be interpreted as combining a posteriori blockmodelling with ERGMs, relaxing the independence assumptions of the former and the homogeneity assumptions of the latter. We propose a Markov chain Monte Carlo al- gorithm for drawing from the joint posterior of the model parameters and latent class indicators