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Objective: To undertake a scoping review to identify methods and diagnostic levels used in determining unintentional, non-fire related carbon monoxide exposure. Design: Online databases and grey literature were searched from 1946 to 2023 identifying 80 papers where carbon monoxide levels were reported. Results: 80 papers were included; 71 research studies and 9 clinical guidelines. Four methods were described: blood carboxyhaemoglobin (arterial or venous blood analysis), carbon monoxide oximetry (SpO2), expired carbon monoxide, and ambient carbon monoxide sampling. Blood analysis methods predominated (60.0% of the papers). Multiple methods of measurement were used in 26 (32.5%) of the papers. Diagnostic levels for carboxyhaemoglobin were described in 54 (67.5%) papers, ranging between 2% and 15%. 26 (32.5%) papers reported diagnostic levels that were adjusted for the smoking status of the patient. Conclusions: Four methods were found for use in different settings. Variability in diagnostic thresholds impairs diagnostic accuracy. Agreement on standardised diagnostic levels is required to enable consistent diagnosis of unintentional, non-fire related carbon monoxide exposure. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. Author summary: In this study, we investigated the computational processes that describe how people derive a sense of confidence in their decisions. In particular, we used computational models to describe how decision confidence is generated from different stimulus features, specifically evidence strength and sensory uncertainty, and determined whether the same computations generalise to both visual and auditory decisions. We tested a range of different computational models from three distinct theoretical classes, where each class of models instantiated different algorithmic hypotheses about the computations that are used to generate confidence. We found that a single class of models, in which confidence is derived from a subjective assessment of the strength of the evidence for a particular choice scaled by an estimate of sensory uncertainty, provided the best account of confidence for both visual and auditory decisions. Our findings suggest that the same type of algorithm is used for evaluating confidence across sensory modalities but that the 'settings' (or parameters) of this process are fine-tuned within each modality. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. 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. 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. 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. 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to investigate perceptions towards a career in psychiatry among medical students and psychiatrists and identify how recruitment into the specialty may be improved.Design/methodology/approach This study locally compares medical student and psychiatric doctor responses to a structured online survey and structured interviews with key managerial figures in the Humber NHS Foundation Trust.Findings Comparison across two main areas (pre-decision exposure to psychiatry and reasons for considering a psychiatric career) found that both students and doctors were influenced to make a choice about a career in psychiatry during medical school. Medical students found compatibility with family life to be more important when considering psychiatry, whereas doctors cited content-based reasons as significant pull factors. Stigma and fear of being harmed deterred some students from choosing a career in psychiatry. Structured interview responses reiterated the importance of pre-medical school and undergraduate mentorship in bolstering future recruitment to psychiatry.Practical implications Medical students perceive certain career issues differently to their postgraduate counterparts. Widening the content-based appeal of psychiatry and optimising the medical school experience of the specialty via varied and high-quality placements may be a key step towards tackling the national shortfall in qualified psychiatrists.Originality/value This is the first published study comparing medical student and psychiatric doctor perceptions of a career in psychiatry. [ABSTRACT FROM AUTHOR]

The article discusses the major international platform for collaboration to agree targets for greenhous gas emissions reductions. Topics discussed include the United Nations Framework Convention on Climate Change in 1992, adoption of the 17 Sustainable Development Goals, and the number of parties that have signed the Paris Agreement as of November 2016.

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 (χ2 = 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: The Coloboma mouse carries a ∼2 cM deletion encompassing the SNAP25 gene and has a hyperactive phenotype similar to that of ADHD. Such mice are 3 fold more active compared to their control littermates. Genetic association studies support a role for allelic variants of the human SNAP25 gene in predisposing to ADHD. Methods/Principal Findings: We performed association analysis across the SNAP25 gene in 1,107 individuals (339 ADHD trios). To assess the functional relevance of the SNAP25-ADHD associated allele, we performed quantitative PCR on post-mortem tissue derived from the inferior frontal gyrus of 89 unaffected adults. Significant associations with the A allele of SNP rs362990 (χ2 = 10, p-corrected = 0.019, OR = 1.5) and three marker haplotypes (rs6108461, rs362990 and rs362998) were observed. Furthermore, a significant additive decrease in the expression of the SNAP25 transcript as a function of the risk allele was also observed. This effect was detected at the haplotype level, where increasing copies of the ADHD-associated haplotype reduced the expression of the transcript. Conclusions: Our data show that DNA variation at SNAP25 confers risk to ADHD and reduces the expression of the transcript in a region of the brain that is critical for the regulation of attention and inhibition. [ABSTRACT FROM AUTHOR]

Pharmacological evidence suggests the importance of noradrenergic and other monoaminergic neurotransmitters in the aetiology and treatment of attention deficit hyperactivity disorder (ADHD). Until recently, the genes of the noradrenergic pathway were not intensively investigated in ADHD compared to dopaminergic and serotonergic candidates. In this study, 91 SNP markers of 14 noradrenergic genes (an average density of one SNP per 4.5 kbp) were examined in ADHD samples from Ireland and Australia. Although suggestive evidence of association (nominal p ≤ 0.05) with the genes SLC6A2, ADRA1A, ADRA1B and ADRA2B was observed, none remained significant after permutation adjustments. In contrast, haplotype analyses demonstrated a significant association between ADHD and a SLC6A2 haplotype comprising the markers rs36009, rs1800887, rs8049681, rs2242447 and rs9930182 (χ = 9.39, p-corrected = 0.019, OR = 1.51). A rare ADRA1B haplotype made of six SNPs (rs2030373, rs6884105, rs756275, rs6892282, rs6888306 and rs13162302) was also associated (χ = 7.79, p-corrected = 0.042 OR = 2.74) with the disorder. These findings provide evidence of a contribution of the noradrenaline system to the genetic aetiology of ADHD. The observed haplotype association signals may be driven by as yet unidentified functional risk variants in or around the associated regions. Functional genomic analysis is warranted to determine the biological mechanism of the observed association. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that individuals with schizophrenia (SZ) are impaired in their ability to imitate gestures and movements generated by others. This impairment in imitation may be linked to difficulties in generating and maintaining internal representations in working memory (WM). We used a novel quantitative technique to investigate the relationship between WM and imitation ability. SZ outpatients and demographically matched healthy control (HC) participants imitated hand gestures. In Experiment 1, participants imitated single gestures. In Experiment 2, they imitated sequences of 2 gestures, either while viewing the gesture online or after a short delay that forced the use of WM. In Experiment 1, imitation errors were increased in SZ compared with HC. Experiment 2 revealed a significant interaction between imitation ability and WM. SZ produced more errors and required more time to imitate when that imitation depended upon WM compared with HC. Moreover, impaired imitation from WM was significantly correlated with the severity of negative symptoms but not with positive symptoms. In sum, gesture imitation was impaired in schizophrenia, especially when the production of an imitation depended upon WM and when an imitation entailed multiple actions. Such a deficit may have downstream consequences for new skill learning. [ABSTRACT FROM PUBLISHER]

Background: This study explored the association between three measures of working memory ability and genetic variation in a range of catecholamine genes in a sample of children with ADHD. Methods: One hundred and eighteen children with ADHD performed three working memory measures taken from the CANTAB battery (Spatial Span, Delayed-match-to-sample, and Spatial Working Memory). Associations between performance on working memory measures and allelic variation in catecholamine genes (including those for the noradrenaline transporter [NET1], the dopamine D4 and D2 receptor genes [DRD4; DRD2], the gene encoding dopamine beta hydroxylase [DBH] and catechol-O-methyl transferase [COMT]) were investigated using regression models that controlled for age, IQ, gender and medication status on the day of test. Results: Significant associations were found between performance on the delayed-match-to-sample task and COMT genotype. More specifically, val/val homozygotes produced significantly more errors than did children who carried a least one met allele. There were no further associations between allelic variants and performance across the other working memory tasks. Conclusions: The working memory measures employed in the present study differed in the degree to which accurate task performance depended upon either the dynamic updating and/or manipulation of items in working memory, as in the spatial span and spatial working memory tasks, or upon the stable maintenance of representations, as in the delay-match-to-sample task. The results are interpreted as evidence of a relationship between tonic dopamine levels associated with the met COMT allele and the maintenance of stable working memory representations required to perform the delayed-match-to-sample-task. [ABSTRACT FROM AUTHOR]

Olfactory identification deficit appears to be an enduring feature of schizophrenia, but it is unclear whether it is specific to schizophrenia or present in psychotic disorders in general. The aim of the present study was to compare olfactory identification and olfactory preference in schizophrenia and bipolar disorder. Individuals with schizophrenia or bipolar disorder and demographically matched healthy participants were given the University of Pennsylvania Smell Identification Test (UPSIT) to assess olfactory identification ability. To examine olfactory hedonic judgment, participants were also asked to indicate their preference for each UPSIT item on a 5-point rating scale, immediately after odor identification. Clinical symptoms and social competence were also assessed. Both schizophrenic and bipolar groups showed olfactory identification deficits compared with the healthy controls, but schizophrenic patients were more impaired than bipolar patients on the UPSIT accuracy. Interestingly, both bipolar and schizophrenic patients rated odors to be more pleasant than did healthy controls, but all groups preferred odors that they could correctly identify to unidentified smells. Restricted range of preference ratings was associated with the severity of negative symptoms in schizophrenia, and with mania in bipolar disorder. Social competence was associated with better olfactory identification performance. These findings suggest that olfactory identification and preference are compromised in bipolar disorder as well as in schizophrenia, but the precise nature of these abnormalities needs to be further elucidated. [ABSTRACT FROM AUTHOR]

Background: While much is known about the role of prefrontal cortex (PFC) in working memory (WM) deficits of schizophrenia, the nature of the relationship between cognitive components of WM and brain activation patterns remains unclear. We aimed to elucidate the neural correlates of the maintenance component of verbal WM by examining correct and error trials with event-related fMRI. Methodology/Findings: Twelve schizophrenia patients (SZ) and thirteen healthy control participants (CO) performed a phonological delayed-matching-to-sample-task in which a memory set of three nonsense words was presented, followed by a 6-seconds delay after which a probe nonsense word appeared. Participants decided whether the probe matched one of the targets, and rated the confidence of their decision. Blood-oxygen-level-dependent (BOLD) activity during WM maintenance was analyzed in relation to performance (correct/error) and confidence ratings. Frontal and parietal regions exhibited increased activation on correct trials for both groups. Correct and error trials were further segregated into true memory, false memory, guess, and true error trials. True memory trials were associated with increased bilateral activation of frontal and parietal regions in both groups but only CO showed deactivation in PFC. There was very little maintenancerelated cortical activity during guess trials. False memory was associated with increased left frontal and parietal activation in both groups. Conclusion: These findings suggest that a wider network of frontal and parietal regions support WM maintenance in correct trials compared with error trials in both groups. Furthermore, a more extensive and dynamic pattern of recruitment of the frontal and parietal networks for true memory was observed in healthy controls compared with schizophrenia patients. These results underscore the value of parsing the sources of memory errors in fMRI studies because of the non-linear nature of the brain-behavior relationship, and suggest that group comparisons need to be interpreted in more specific behavioral contexts. [ABSTRACT FROM AUTHOR]

The social significance of imitation is that it provides internal tools for understanding the actions of others by simulating or forming internal representations of these actions. Imitation plays a central role in human social behavior by mediating diverse forms of social learning. However, imitation and simulation ability in schizophrenia has not been adequately addressed. The major aim of the present study was to investigate imitation ability in schizophrenia patients and healthy individuals by examining simple motor imitation that involved the replication of meaningless manual and oral gestures, and the imitation of emotional facial expressions, which has implications for mentalizing. A secondary aim of the present study was to investigate the relationships among imitation ability, social functioning, and working memory. Subjects were asked to mimic hand gestures, mouth movements, and facial expressions of others, online. Clinical symptoms, social competence, and working memory were also assessed. Patients with schizophrenia were significantly impaired on all imitation tasks. Imitation errors were significantly correlated with reduced social competence and increased negative symptoms. However, imitation ability was only weakly associated with working memory. To summarize, the present study examined the ability of patients with schizophrenia to imitate the behaviors demonstrated by others. The results indicate a fundamental impairment in imitation ability in schizophrenia and implicate a possible difficulty in simulation. Further research to determine the neural and developmental origins of this difficulty could be extremely helpful in elucidating the role of simulation in schizophrenia and to establish the complex relationships among mental representation, imitation, and social cognition. [ABSTRACT FROM PUBLISHER]

HIV vaccine testing in primates is an important method for determining the possibility of vaccine benefit in humans. Goals of HIV-1 vaccination include establishing neutralizing antibodies and a strong CD8+ T-cell response. We tested a novel vaccine conjugate for its ability to elicit relevant immune responses to HIV proteins and peptides in rhesus macaques. A neutralizing epitope, V3 loop peptide from HIV-1 envelope, was coupled to heat-inactivated Brucella abortus (V3-HKBA). Rhesus macaques were immunized with this conjugate in the anterior thigh. After two immunizations V3-specific antibodies were found in the sera and at mucosal sites. Neutralizing activity of these antibodies was demonstrated by syncytia inhibition assays. Cellular immune recall responses were demonstrated by antigen-specific induction of interferon-gamma and Regulation on Activation Noraml T Cell Expressed and Secreted (RANTES) secretion in vitro. These results confirm and extend preliminary studies in mice that suggest HKBA is an effective carrier that promotes neutralizing antibody secretion at relevant mucosal sites, as well as cellular immune responses that are correlated with viral protection. [ABSTRACT FROM AUTHOR]

We argue that autism and psychosis spectrum disorders cannot be conceptualized as polar extremes of mentalizing ability. We raise two main objections: (1) the autistic-psychotic continuum, as conceptualized by the authors, excludes defining features of schizophrenia spectrum: negative symptoms, which correlate more strongly with mentalizing impairments; and (2) little evidence exists for a relationship between mentalizing ability and positive symptoms. [ABSTRACT FROM AUTHOR]