The distribution of parent-reported attention-deficit/hyperactivity disorder and subclinical autistic traits in children with and without an ADHD diagnosis.

Background: Autistic traits are often reported to be elevated in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). However, the distribution of subclinical autistic traits in children with ADHD has not yet been established; knowing this may have important implications for diagnostic and intervention processes. The present study proposes a preliminary model of the distribution of parent-reported ADHD and subclinical autistic traits in two independent samples of Australian children with and without an ADHD diagnosis. Methods: Factor mixture modelling was applied to Autism Quotient and Conners' Parent Rating Scale - Revised responses from parents of Australian children aged 6-15 years who participated in one of two independent studies. Results: A 2-factor, 2-class factor mixture model with class varying factor variances and intercepts demonstrated the best fit to the data in both discovery and replication samples. The factors corresponded to the latent constructs of 'autism' and 'ADHD', respectively. Class 1 was characterised by low levels of both ADHD and autistic traits. Class 2 was characterised by high levels of ADHD traits and low-to-moderate levels of autistic traits. The classes were largely separated along diagnostic boundaries. The largest effect size for differences between classes on the Autism Quotient was on the Social Communication subscale. Conclusions: Our findings support the conceptualisation of ADHD as a continuum, whilst confirming the utility of current categorical diagnostic criteria. Results suggest that subclinical autistic traits, particularly in the social communication domain, are unevenly distributed across children with clinically significant levels of ADHD traits. These traits might be profitably screened for in assessments of children with high ADHD symptoms and may also represent useful targets for intervention.

Modality independent or modality specific? Common computations underlie confidence judgements in visual and auditory decisions.

The mechanisms that enable humans to evaluate their confidence across a range of different decisions remain poorly understood. To bridge this gap in understanding, we used computational modelling to investigate the processes that underlie confidence judgements for perceptual decisions and the extent to which these computations are the same in the visual and auditory modalities. Participants completed two versions of a categorisation task with visual or auditory stimuli and made confidence judgements about their category decisions. In each modality, we varied both evidence strength, (i.e., the strength of the evidence for a particular category) and sensory uncertainty (i.e., the intensity of the sensory signal). We evaluated several classes of computational models which formalise the mapping of evidence strength and sensory uncertainty to confidence in different ways: 1) unscaled evidence strength models, 2) scaled evidence strength models, and 3) Bayesian models. Our model comparison results showed that across tasks and modalities, participants take evidence strength and sensory uncertainty into account in a way that is consistent with the scaled evidence strength class. Notably, the Bayesian class provided a relatively poor account of the data across modalities, particularly in the more complex categorisation task. Our findings suggest that a common process is used for evaluating confidence in perceptual decisions across domains, but that the parameter settings governing the process are tuned differently in each modality. Overall, our results highlight the impact of sensory uncertainty on confidence and the unity of metacognitive processing across sensory modalities.

Outcome Expectancies, Effects, and Mechanisms of Brief Training in Mindfulness Meditation vs. Loving-Kindness Meditation vs a Control Condition for Pain Management: A Randomized Pilot Study.

This study investigated the analgesic effects of a single session of mindfulness meditation (MM) and loving-kindness meditation (LKM) relative to a control. A total of 100 adults with chronic or current problematic pain completed a survey and were randomized to a 20-minute MM, LKM, or audiobook control. Co-primary outcomes of pain intensity and unpleasantness and mediators of mindfulness and self-compassion were assessed pre- and posttraining. Expectancies were assessed pretraining. Pain type (chronic vs current problematic) was a covariate. Relative to the control, higher expectancies were reported for MM and LKM (P < .001). MM (d = 0.41, P = .032) and LKM (d = 0.38, P = .027) had medium effects on pain intensity, with greater decreases than control (d = 0.05, P = .768). All conditions had small effects on unpleasantness. Mindful observing increased more within MM (d = 0.52, P = .022) and the control (d = 0.50, P = .011) than LKM (d = 0.12, P = .50); self-compassion increased more in LKM (d = 0.36, P = .042) than MM (d = 0.27, P = .201) and the control (d = 0.22, P = .249). The mediation models were nonsignificant. Pain type was a nonsignificant covariate. Overall, MM and LKM were associated with positive expectancies and small-medium pain intensity reductions, which did not differ by pain type. Although MM and LKM were associated with changes in theorized mediators, these changes did not underlie improvement.

Task difficulty and private speech in typically developing and at-risk preschool children.

Private speech is a cognitive tool to guide thinking and behavior, yet its regulatory use in atypical development remains equivocal. This study investigated the influence of task difficulty on private speech in preschool children with attention or language difficulties. Measures of private speech use, form and content were obtained while 52 typically developing and 25 developmentally at-risk three- to four-year-old children completed Duplo construction and card sort tasks, each comprising two levels of challenge. In line with previous research, developmentally at-risk children used less internalized private speech than typically developing peers. However, both typically developing and at-risk children demonstrated a similar regulatory private speech response to difficulty with no systematic evidence of group difference. This was captured by an increase in all utterances, reduced private speech internalization, and more frequent forethought and self-reflective content. Results support the hypothesis of delayed private speech internalization but not regulatory deviance in atypical development.

Health and socioeconomic resource provision for older people in South Asian countries: Bangladesh, India, Nepal, Pakistan and Sri Lanka evidence from NEESAMA.

BACKGROUND: The global population is ageing rapidly, with low- and middle-income countries (LMICs) undergoing a fast demographic transition. As the number of older adults in LMICs increases, services able to effectively address their physical and mental health needs will be increasingly important. OBJECTIVE: We review the health and socioeconomic resources currently available for older people in South Asian countries, Bangladesh, India, Nepal, Pakistan and Sri Lanka, to identify gaps in available resources and assess areas for improvement. METHODS: We conducted a search of grey and published literature via Google Search, Compendex, EBSCO, JSTOR, Medline, Ovid, ProQuest databases, Scopus and Web of Science. Data on population demographics, human resources, health funding and social protection for older people were extracted. Local informants were consulted to supplement and verify the data. RESULTS: In the study countries, the number of health professionals with expertise in elderly care was largely unknown, with minimal postgraduate training programmes available in elderly medicine or psychiatry. Older adults are therefore cared for by general physicians, nurses and community health workers, all of whom are present in insufficient numbers per capita. Total average healthcare expenditure was 2.5-5.5% of GDP, with 48.1-72.0% of healthcare costs covered by out-of-pocket payments. Pakistan did not have a social pension; only India and Nepal offered financial assistance to people with dementia; and all countries had disproportionately low numbers of care elderly homes. CONCLUSIONS: Inadequate healthcare funding, a shortage of healthcare professionals and insufficient government pension and social security schemes are significant barriers to achieving universal health coverage in LMICs. Governing bodies must expand training programmes for healthcare providers for older adults, alongside increasing social protection to improve access to those in need and to prevent catastrophic health expenditure.

Making a HIIT: study protocol for assessing the feasibility and effects of co-designing high-intensity interval training workouts with students and teachers.

BACKGROUND: High-intensity interval training (HIIT) is an effective strategy for improving a variety of health outcomes within the school setting. However, there is limited research on the implementation of school-based HIIT interventions and the integration of HIIT within the Health and Physical Education (HPE) curriculum. The aims of the Making a HIIT study are to: 1) describe the methodology and evaluate the feasibility of co-designing HIIT workouts with students and teachers in HPE; 2) determine the effect of co-designed HIIT workouts on cardiorespiratory and muscular fitness, and executive function; 3) understand the effect of co-design on students' motivation, enjoyment, and self-efficacy towards the workouts; and 4) evaluate the implementation of the intervention. METHODS: Three schools will participate. Within each school, three different groups will be formed from Year 7 and 8 classes: 1) Co-Designers; 2) HIIT Only; and 3) Control. The study will include two phases. In phase one, Group 1 will co-design HIIT workouts as part of the HPE curriculum using an iterative process with the researcher, teacher, and students as collaborators. This process will be evaluated using student discussions, student surveys, and teacher interviews. In phase two, Groups 1 and 2 will use the co-designed 10-minute HIIT workouts in HPE for 8-weeks. Group 3 (control) will continue their regular HPE lessons. All students will participate in cardiorespiratory fitness, muscular fitness, and executive function assessments before and after the HIIT program or control period. Students will complete questionnaires on their motivation, enjoyment, and self-efficacy of the workouts. Differences between groups will be assessed using linear regressions to account for covariates. Heart rate and rating of perceived exertion will be collected during each HIIT session. The implementation will be evaluated using the Framework for Effective Implementation. Ethical approval was granted by the University of Queensland Human Research Ethics Committee and other relevant bodies. DISCUSSION: This study will be the first to co-design HIIT workouts with teachers and students within the HPE curriculum. As this study relies on co-design, each HIIT workout will differ, which will add variability between HIIT workouts but increase the ecological validity of the study. TRIAL REGISTRATION: ACTRN, ACTRN12622000534785, Registered 5 April 2022 - Retrospectively registered, https://www.anzctr.org.au/ACTRN12622000534785.aspx.

Media-multitasking and cognitive control across the lifespan.

The exponential rise in technology use over the past decade, and particularly during the COIVD-19 pandemic, has been accompanied by growing concern regarding the consequences of this technology use for our cognition. Previous studies on the influence of technology-multitasking (the use of two or more technologies simultaneously) on cognitive performance have provided mixed results. However, these past studies have generally ignored the considerable developmental trajectories that cognitive abilities undergo across the lifespan. In a large community-based science project we investigated the relationship between media-multitasking and cognitive flexibility (multitasking ability) in participants aged 7-70 years. Higher levels of every-day technology multitasking were associated with higher levels of multitasking performance across an age range in which multitasking ability undergoes developmental change. These findings suggest that age is an important moderator of the relationship between technology use and cognition.

Change in Brain Oscillations as a Mechanism of Mindfulness-Meditation, Cognitive Therapy, and Mindfulness-Based Cognitive Therapy for Chronic Low Back Pain.

OBJECTIVE: Psychological treatments for chronic low back pain (CLBP) are effective. However, limited research has investigated their neurophysiological mechanisms. This study examined electroencephalography- (EEG-) assessed brain oscillation changes as potential mechanisms of cognitive therapy (CT), mindfulness-meditation (MM), and mindfulness-based cognitive therapy (MBCT) for CLBP. The a priori bandwidths of interest were changes in theta, alpha and beta power, measured at pre- and post-treatment. DESIGN: A secondary analysis of a clinical trial. SETTING: University of Queensland Psychology Clinic. SUBJECTS: Adults (N = 57) with CLBP who completed pre- and post-treatment EEG and pain outcome assessments. METHODS: EEG data were examined for five regions of interest (ROIs); the primary outcome was pain intensity. RESULTS: A significant reduction in theta (P=.015) and alpha (P=.006) power in the left frontal ROI across all treatments was found, although change in theta and alpha power in this region was not differentially associated with outcome across treatments. There were significant reductions in beta power in all five ROIs across all treatments (P≤.013). Beta power reduction in the central ROI showed a significant association with reduced pain intensity in MBCT only (P=.028). Changes in other regions were not statistically significant. CONCLUSIONS: These findings provide support for the capacity of psychological CLBP treatments to induce changes in brain activity. The reduced beta power in all five ROIs indicated that all three treatments engendered a state of lowered cortical arousal. The growing body of research in this area could potentially inform novel directions towards remedying central nervous system abnormalities associated with CLBP.

Training tomorrow's doctors: the impact of a Student Selected Component in Global Health during medical school.

This article was migrated. The article was marked as recommended. Introduction:Several reports highlight the importance of global health education (GHE) for training tomorrow's doctors. In 2006, Newcastle University Medical School developed a Student Selected Component (SSC) in Global Health. We followed up students who completed the SSC to assess the impact on their experience as practising clinicians and postgraduate career development. Methods:We developed an electronic survey including questions about speciality choice, postgraduate qualifications, extracurricular activity and international work. Surveys were sent to 72 SSC participants identified between 2006-2017 through the Newcastle University Alumni and Supporters network and social media. Results: Surveys were returned by 37 (51%) SSC participants; 25 (71%) and 16 (46%) believed the SSC had influenced their clinical practice and career choice, respectively. Twenty-two (59%) obtained an intercalated degree programme, of whom nine (24%) did a Masters programme specifically in Global Health and four (11%), and two (5%) completed a Masters degree in Epidemiology and Control of Infectious Diseases respectively, both key themes within GHE. Four (11%) undertook, and 10 (29%) were considering postgraduate study related to global health, of whom three (9%) specified undertaking a Diploma in Tropical Medicine and Hygiene (DTM&H) and one (3%) studying a Masters degree in Public Health. Five (14%) had, and 19 (54%) were planning to work abroad, most referring to work in humanitarian or low resource settings and GHE programmes. Discussion and Conclusion:Participation in an SSC in Global Health may affect positive change in students' clinical practice and help inform academic and clinical career choice. Whilst a causative relationship cannot be inferred, the experience may support or increase the pursuit of additional global health-related qualifications, research and international health work. Medical schools that endeavour to produce graduates motivated to tackle our society's global health challenges should champion comprehensive global health modules for students.

Global health education in UK medical schools: a review of undergraduate university curricula.

INTRODUCTION: In recognition of our increasingly globalised world, global health is now a required component of the medical school curriculum in the UK. We review the current provision of global health education (GHE) in UK medical schools to identify gaps in compulsory teaching. METHODS: We conducted a review of the literature to inform a two-part electronic survey of global health compulsory teaching, optional teaching and pre-elective training. Surveys were sent to all 33 UK medical schools for completion by the faculty lead on global health and the nominated final year student representative. RESULTS: Surveys were returned by 29 (88%) medical school faculty and 15 (45%) medical student representatives; 24 (83%) faculty and 10 (67%) students reported including GHE in the core curriculum; however, there was wide variation in the learning outcomes covered. On average 75% of faculty and 82% of students reported covering recommended global health themes 'global burden of disease', 'socioeconomic and environmental determinants of health', 'human rights and ethics', and 'cultural diversity and health', while only 48% of faculty and 33% of students reported teaching on 'health systems' and 'global health governance'. Almost all institutions offered optional global health programmes and most offered some form of pre-elective training, although content and delivery were variable. CONCLUSION: Over the last decade, the inclusion of global health in the core curriculum of UK medical schools has increased dramatically. Yet, despite interest among students, significant gaps are apparent in current GHE. Governing bodies in medical education should establish a comprehensive national strategy to help improve access to fundamental GHE for all medical students.

Moderators of Mindfulness Meditation, Cognitive Therapy, and Mindfulness-Based Cognitive Therapy for Chronic Low Back Pain: A Test of the Limit, Activate, and Enhance Model.

This study examined psychosocial pain treatment moderation in a secondary analysis of a trial that compared cognitive therapy (CT), mindfulness-meditation (MM), and mindfulness-based cognitive therapy (MBCT) for chronic low back pain (CLBP). The Limit, Activate, and Enhance (LA&E) model of moderation provided a framework for testing a priori hypotheses. Adult participants (N = 69) with CLBP completed a pretreatment assessment of hypothesized moderators: pain catastrophizing, brain state as assessed by electroencephalogram, mindful observing, and nonreactivity. Outcomes were pain interference, characteristic pain intensity, physical function, and depression, assessed at pre- and post-treatment. Moderation analyses found significant interaction effects, specifically: 1) higher and lower baseline pain catastrophizing was associated with greater improvement in pain intensity in MM and MBCT, respectively; 2) higher baseline theta power was associated with greater improvement in depression in MBCT and interfered with response to CT; 3) lower baseline nonreactivity was associated with greater improvement in physical function in MM while higher nonreactivity was associated with greater improvement in MBCT. The findings support the possibility that different patients are more or less likely to benefit from various treatments. Theory-driven moderation research has the capacity to inform the development of patient-treatment matching algorithms to optimize outcome. PERSPECTIVE: This study presents preliminary findings from theory-driven tests of the moderators of mindfulness meditation, cognitive therapy, and mindfulness-based cognitive therapy for chronic low back pain. The results of such analyses may inform the understanding of for whom various evidence-based psychosocial pain treatments may engender the most meaningful benefits.

Self-directed speech and self-regulation in childhood neurodevelopmental disorders: Current findings and future directions.

Self-directed speech is considered an important developmental achievement as a self-regulatory mediator of thinking and behavior. Atypical self-directed speech is often implicated in the self-regulatory challenges characteristic of children with neurodevelopmental disorders. A growing body of evidence provides snapshots across age-levels and diagnoses, often presenting conflicting results. This systematic review is undertaken to impose clarity on the nature, extent, and self-regulatory implications of self-directed speech interruption in children with developmental language disorder (DLD), autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD).A rigorous search process of relevant databases (i.e., PsychInfo, PubMed, CINAHL, ERIC) uncovered 19 relevant peer-reviewed articles that investigate self-directed speech in children with neurodevelopmental disorders. Consistent across the research, children with DLD, ASD, and ADHD present with differential development and use of self-directed speech.In its synthesis of findings, this systematic review clearly explicates the differential ontogenesis of self-directed speech in neurodevelopmental disorders and interprets the self-regulatory implications for children with DLD, ASD, and ADHD. Furthermore, the review spotlights important future research directions to better understand the mechanistic relationship between self-directed speech and self-regulation.

Rapid recalibration of temporal order judgements: Response bias accounts for contradictory results.

Recent history influences subsequent perception, decision-making and motor behaviours. In this article, we address a discrepancy in the effects of recent sensory history on the perceived timing of auditory and visual stimuli. In the synchrony judgement (SJ) task, similar timing relationships in consecutive trials seem more synchronous (i.e. less like the repeated temporal order). This effect is known as rapid recalibration and is consistent with a negative perceptual aftereffect. Interestingly, the opposite is found in the temporal order judgement (TOJ) task (positive rapid recalibration). We aimed to determine whether a simple bias to repeat judgements on consecutive trials (choice-repetition bias) could account for the discrepant results in these tasks. Preliminary simulations and analyses indicated that a choice-repetition bias could produce apparently positive rapid recalibration in the TOJ and not the SJ task. Our first experiment revealed no evidence of rapid recalibration of TOJs, but negative rapid recalibration of associated confidence. This suggests that timing perception was rapidly recalibrated, but that the negative recalibration effect was obfuscated by a positive bias effect. In our second experiment, we experimentally mitigated the choice-repetition bias effect and found negative rapid recalibration of TOJs. We therefore conclude that timing perception is negatively rapidly recalibrated, and this is observed consistently across timing tasks. These results contribute to a growing body of evidence that indicates multisensory perception is constantly undergoing recalibration, such that perceptual synchrony is maintained. This work also demonstrates that participants' task responses reflect judgements that are contaminated by independent biases of perception and decision-making.

An evaluation of the behavioral inhibition and behavioral activation system (BIS-BAS) model of pain.

OBJECTIVE: This study evaluated the behavioral inhibition and activation system (BIS-BAS) model of pain. Frontal alpha asymmetry (FAA) as a possible neurophysiological correlate of the BIS-BAS was also explored, as was the role of personality factors. RESEARCH METHOD: A cross-sectional study was completed at the University of (The University of Queensland). The sample was N = 69 adults with chronic low back pain. Self-report and data were collected as a part of a treatment outcome study. Correlational analyses were conducted between theorized BIS-BAS-related measures of cognitions (catastrophizing, control beliefs), emotion (depression, anxiety, happiness), and behavior (avoidance, engagement). Correlations and hierarchical regression were used to explore the association between these measures, pain intensity, personality factors, and FAA. RESULTS: As hypothesized, the correlations between the BIS and BAS measures were all negative and mostly significant (ps < .05). The BIS-related measures were significantly positively associated with each other and Neuroticism (ps <.01). The BAS-related measures were positively correlated with each other and Extraversion, with most of these associations statistically significant. While pain intensity was significantly associated with several BIS and BAS measures (ps < .05), FAA was not significantly associated with pain or any BIS-BAS domain. BAS-related measures were most strongly associated with pain intensity (ΔR² = .13). CONCLUSIONS: Few studies have concurrently investigated the intersection between brain state, pain-related variables and psychosocial factors. This is the first study to test these associations from the perspective of a BIS-BAS model of pain. The findings provide preliminary support for the central tenets of this framework. The clinical implications of the findings are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Scopolamine Reduces Electrophysiological Indices of Distractor Suppression: Evidence from a Contingent Capture Task.

Limited resources for the in-depth processing of external stimuli make it necessary to select only relevant information from our surroundings and to ignore irrelevant stimuli. Attentional mechanisms facilitate this selection via top-down modulation of stimulus representations in the brain. Previous research has indicated that acetylcholine (ACh) modulates this influence of attention on stimulus processing. However, the role of muscarinic receptors as well as the specific mechanism of cholinergic modulation remains unclear. Here we investigated the influence of ACh on feature-based, top-down control of stimulus processing via muscarinic receptors by using a contingent capture paradigm which specifically tests attentional shifts toward uninformative cue stimuli which display one of the target defining features In a double-blind, placebo controlled study we measured the impact of the muscarinic receptor antagonist scopolamine on behavioral and electrophysiological measures of contingent attentional capture. The results demonstrated all the signs of functional contingent capture, i.e., attentional shifts toward cued locations reflected in increased amplitudes of N1 and N2Pc components, under placebo conditions. However, scopolamine did not affect behavioral or electrophysiological measures of contingent capture. Instead, scopolamine reduced the amplitude of the distractor-evoked Pd component which has recently been associated with active suppression of irrelevant distractor information. The findings suggest a general cholinergic modulation of top-down control during distractor processing.

The Effects of Methylphenidate on the Neural Signatures of Sustained Attention.

BACKGROUND: Although it is well established that methylphenidate (MPH) enhances sustained attention, the neural mechanisms underpinning this improvement remain unclear. We examined how MPH influenced known electrophysiological precursors of lapsing attention over different time scales. METHODS: We measured the impact of MPH, compared with placebo, on behavioral and electrocortical markers while healthy adults (n = 40) performed a continuous monitoring paradigm designed to elicit attentional lapses. RESULTS: MPH led to increased rates of target detection, and electrophysiological analyses were conducted to identify the mechanisms underlying these improvements. Lapses of attention were reliably preceded by progressive increases in alpha activity that emerged over periods of several seconds. MPH led to an overall suppression of alpha activity across the entire task but also diminished the frequency of these maladaptive pretarget increases through a reduction of alpha variability. A drug-related linear increase in the amplitude of the frontal P3 event-related component was also observed in the pretarget timeframe (3 or 4 seconds). Furthermore, during immediate target processing, there was a significant increase in the parietal P3 amplitude with MPH, indicative of enhanced perceptual evidence accumulation underpinning target detection. MPH-related enhancements occurred without significant changes to early visual processing (visual P1 and 25-Hz steady-state visual evoked potential). CONCLUSIONS: MPH serves to reduce maladaptive electrophysiological precursors of lapsing attention by acting selectively on top-down endogenous mechanisms that support sustained attention and target detection with no significant effect on bottom-up sensory excitability. These findings offer candidate markers to monitor the therapeutic efficacy of psychostimulants or to predict therapeutic responses.

Transferability of Training Benefits Differs across Neural Events: Evidence from ERPs.

Humans can show striking capacity limitations in sensorimotor processing. Fortunately, these limitations can be attenuated with training. However, less fortunately, training benefits often remain limited to trained tasks. Recent behavioral observations suggest that the extent to which training transfers may depend on the specific stage of information processing that is being executed. Training benefits for a task that taps the consolidation of sensory information (sensory encoding) transfer to new stimulus-response mappings, whereas benefits for selecting an appropriate action (decision-making/response selection) remain specific to the trained mappings. Therefore, training may have dissociable influences on the neural events underlying subsequent sensorimotor processing stages. Here, we used EEG to investigate this possibility. In a pretraining baseline session, participants completed two four-alternative-choice response time tasks, presented both as a single task and as part of a dual task (with another task). The training group completed a further 3,000 training trials on one of the four-alternative-choice tasks. Hence, one task became trained, whereas the other remained untrained. At test, a negative-going component that is sensitive to sensory-encoding demands (N2) showed increased amplitudes and reduced latencies for trained and untrained mappings relative to a no-train control group. In contrast, the onset of the stimulus-locked lateralized readiness potential, a component that reflects the activation of motor plans, was reduced only for tasks that employed trained stimulus-response mappings, relative to untrained stimulus-response mappings and controls. Collectively, these results show that training benefits are dissociable for the brain events that reflect distinct sensorimotor processing stages.

Identification and functional characterisation of a novel dopamine beta hydroxylase gene variant associated with attention deficit hyperactivity disorder.

OBJECTIVES: Dysregulation in neurotransmitter signalling has been implicated in the aetiology of attention deficit hyperactivity disorder (ADHD). Polymorphisms of the gene encoding dopamine beta hydroxylase (DBH) have been reported to be associated with ADHD; however, small sample sizes have led to inconsistency. METHODS: We conducted transmission disequilibrium test analysis in 794 nuclear families to examine the relationship between DBH and ADHD. The effects of the ADHD-associated polymorphisms on gene expression were assessed by luciferase reporter assays in a human neuroblastoma cell line, SH-SY5Y. RESULTS: A SNP within the 3' untranslated region of DBH rs129882 showed a significant association with ADHD (χ(2) = 9.71, p = 0.0018, OR = 1.37). This association remained significant after Bonferroni correction for multiple testing (p = 0.02). Further, allelic variation in rs129882 significantly impacted luciferase expression. Specifically, the C allele of the ADHD-associated rs129882 SNP produced a 2-fold decrease (p < 0.001) in luciferase activity. CONCLUSIONS: These data demonstrate for the first time that a DBH gene variant, rs129882, which confers risk to ADHD is also associated with reduced in vitro gene expression. Reduced DBH expression would be consistent with decreased conversion of dopamine to noradrenaline and thus with a relative hypo-noradrenergic state in ADHD.

Visuospatial imagery and working memory in schizophrenia.

INTRODUCTION: The ability to form mental images that reconstruct former perceptual experiences is closely related to working memory (WM) ability. However, whereas WM deficits are established as a core feature of schizophrenia, an independent body of work suggests that mental imagery ability is enhanced in the disorder. Across two experiments we investigated mental imagery in schizophrenia and its relationship with WM. METHODS: In Experiment 1, individuals with schizophrenia (SZ: n=15) and matched controls (CO: n=14) completed a mental imagery generation and inspection task and a spatial delayed-response WM task. In Experiment 2, SZ (n=16) and CO (n=16) completed a novel version of the mental imagery task modified to increase WM maintenance demand. RESULTS: In Experiment 1, SZ demonstrated enhanced mental imagery performance, as evidenced by faster response times relative to CO, with preserved accuracy. However, enhanced mental imagery in SZ was accompanied by impaired WM as assessed by the delayed-response task. In Experiment 2, when WM maintenance load was increased, SZ no longer showed superior imagery performance. CONCLUSIONS: We found evidence for enhanced imagery manipulation in SZ despite their WM maintenance deficit. However, this imagery enhancement was abolished when WM maintenance demands were increased. This profile of enhanced imagery manipulation but impaired maintenance could be used to implement novel remediation strategies in the disorder.