243 research outputs found
Mirror neuron brain regions contribute to identifying actions, but not intentions
Previous studies have struggled to determine the relationship between mirror neuron brain regions and two distinct âaction understandingâ processes: identifying actions and identifying the intentions underlying those actions. This may be because the identification of intentions from others' actions requires an initial action identification process. Disruptive transcranial magnetic stimulation was administered to left inferior frontal gyrus (lIFG) during a novel cognitive task to determine which of these âaction understandingâ processes is subserved by mirror neuron brain regions. Participants identified either the actions performed by observed hand actions or the intentions underlying those actions. The extent to which intention identification was disrupted by lIFG (vs. control site) stimulation was dependent on the level of disruption to action identification. We subsequently performed functional magnetic resonance imaging during the same task. During action identification, responses were widespread within mirror neuron areas including lIFG and inferior parietal lobule. However, no independent responses were found in mirror neuron brain regions during intention identification. Instead, responses occurred in brain regions associated with two distinct mentalizing localizer tasks. This supports an account in which mirror neuron brain regions are involved in an initial action identification process, but the subsequent identification of intentions requires additional processing in mentalizing brain regions
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Robust associations between the 20-item prosopagnosia index and the Cambridge face memory test in the general population
Developmental prosopagnosia (DP) is a neurodevelopmental condition, characterised by lifelong face recognition deficits. Leading research groups diagnose the condition using complementary computer-based tasks and self-report measures. In an attempt to standardise the reporting of self-report evidence, we recently developed the 20-Item Prosopagnosia Index (PI20), a short questionnaire measure of prosopagnosic traits suitable for screening adult samples for DP. Strong correlations between scores on the PI20 and performance on the Cambridge Face Memory Test (CFMT) appeared to confirm that individuals possess sufficient insight into their face recognition ability to complete a self-report measure of prosopagnosic traits. However, the extent to which people have insight into their face recognition abilities remains contentious. A lingering concern is that feedback from formal testing, received prior to administration of the PI20, may have augmented the self-insight of some respondents in the original validation study. To determine whether the significant correlation with the CFMT was an artefact of previously delivered feedback, we sought to replicate the validation study in individuals with no history of formal testing. We report highly significant correlations in two independent samples drawn from the general population, confirming i) that a significant relationship exists between PI20 scores and performance on the CFMT, and ii) that this is not dependent on the inclusion of individuals who have previously received feedback. These findings support the view that people have sufficient insight into their face recognition abilities to complete a self-report measure of prosopagnosic traits
The relationship between heartbeat counting and heartbeat discrimination:a meta-analysis
Interoception concerns the perception of the bodyâs internal state. Despite the importance of this ability for health and aspects of higher-order cognition, its measurement remains problematic. Most studies of interoception employ one of two tasks: the heartbeat counting or heartbeat discrimination task. These tasks are thought to index common abilities, an assertion often used to justify the use of a single measure of cardiac interoception. However, mixed findings regarding the relationship between performance on these tasks raises the question of whether they can be used interchangeably to assess interoceptive accuracy, confidence and awareness (âmetacognitionâ). The present study employed a meta-analytical approach to assess the association between these tasks. Pooled findings from 22 studies revealed a small relationship between accuracy scores on the measures. Additional analyses demonstrated a moderate relationship between confidence ratings but no association between measures of interoceptive awareness. These findings question the interchangeable use of the two tasks
Novel theory of mind task demonstrates representation of minds in mental state inference
Theory of mind (ToM), the ability to represent the mental states of oneself and others, is argued to be central to human social experience, and impairments in this ability are thought to underlie several psychiatric and developmental conditions. To examine the accuracy of mental state inferences, a novel ToM task was developed, requiring inferences to be made about the mental states of âTargetsâ, prior participants who took part in a videoed mock interview. Participants also made estimates of the Targetsâ personality traits. These inferences were compared to ground-truth data, provided by the Targets, of their true traits and mental states. Results from 55 adult participants demonstrated that trait inferences were used to derive mental state inferences, and that the accuracy of trait estimates predicted the accuracy of mental state inferences. Moreover, the size and direction of the association between trait accuracy and mental state accuracy varied according to the traitâmental state combination. The accuracy of trait inferences was predicted by the accuracy of participantsâ understanding of trait covariation at the population level. Findings are in accordance with the Mind-space theory, that representation of the Target mind is used in the inference of their mental states
Neural processing associated with cognitive and affective Theory of Mind in adolescents and adults
Theory of Mind (ToM) is the ability to attribute thoughts, intentions and beliefs to others. This involves component processes, including cognitive perspective taking (cognitive ToM) and understanding emotions (affective ToM). This study assessed the distinction and overlap of neural processes involved in these respective components, and also investigated their development between adolescence and adulthood. While data suggest that ToM develops between adolescence and adulthood, these populations have not been compared on cognitive and affective ToM domains. Using fMRI with 15 adolescent (aged 11â16 years) and 15 adult (aged 24â40 years) males, we assessed neural responses during cartoon vignettes requiring cognitive ToM, affective ToM or physical causality comprehension (control). An additional aim was to explore relationships between fMRI data and self-reported empathy. Both cognitive and affective ToM conditions were associated with neural responses in the classic ToM network across both groups, although only affective ToM recruited medial/ventromedial PFC (mPFC/vmPFC). Adolescents add- itionally activated vmPFC more than did adults during affective ToM. The specificity of the mPFC/vmPFC response during affective ToM supports evidence from lesion studies suggesting that vmPFC may integrate affective information during ToM. Furthermore, the differential neural response in vmPFC between adult and adolescent groups indicates developmental changes in affective ToM processing
A contemporary comparison of the effect of shunt type in hypoplastic left heart syndrome on the hemodynamics and outcome at stage 2 reconstruction
ObjectiveWe compare the hemodynamics and perioperative course of shunt type in hypoplastic left heart syndrome at the time of stage 2 reconstruction and longer-term survival.MethodsWe retrospectively reviewed the echocardiograms, catheterizations, and hospital records of all patients who had a stage 1 reconstruction between January 2002 and May 2005 and performed a cross-sectional analysis of hospital survivors.ResultsOne hundred seventy-six patients with hypoplastic left heart syndrome and variants underwent a stage 1 reconstruction with either a right ventricleâpulmonary artery conduit (n = 62) or a modified BlalockâTaussig shunt (n = 114). The median duration of follow-up is 29.1 months (range, 0-57 months). By means of KaplanâMeier analysis, there is no difference in survival at 3 years (right ventricleâpulmonary artery conduit: 73% [95% confidence limit, 59%â83%] vs modified BlalockâTaussig shunt: 69% [95% confidence limit, 59%â77%]; P = .6). One hundred twenty-four patients have undergone stage 2 reconstruction (78 modified BlalockâTaussig shunts and 46 right ventricleâpulmonary artery conduits). At the time of the stage 2 reconstruction, patients with right ventricleâpulmonary artery conduits were younger (153 days [range, 108â340 days]; modified BlalockâTaussig shunt, 176 days [range, 80â318 days]; P = .03), had lower systemic oxygen saturation (73% [range, 58%â85%] vs 77% [range, 57%â89%], P < .01), and had higher preoperative hemoglobin levels (15.8 g/dL [range, 13â21 g/dL] vs 14.8 g/dL [range, 12â19 g/dL], P < .01) compared with those of the modified BlalockâTaussig shunt group. By means of echocardiographic evaluation, there was a higher incidence of qualitative ventricular dysfunction in patients with right ventricleâpulmonary artery conduits (14/46 [31%] vs 9/73 [12%], P = .02). However, no difference was observed in common atrial pressure or the arteriovenous oxygen difference.ConclusionInterim analyses suggest no advantage of one shunt type over another. This report raises concern of late ventricular dysfunction and outcome in patients with a right ventricleâpulmonary artery conduit
Effectiveness of biologics in Australian patients with rheumatoid arthritis: a large observational study: REAL
Background: The comparative effectiveness of biologic treatment regimens in a real world Australian population is unknown. Aim: To assess the effectiveness of biological disease-modifying anti-rheumatic drugs (bDMARD) as monotherapy or in combination with methotrexate and/or other conventional DMARD (cDMARD) for the treatment of rheumatoid arthritis (RA). Methods: A retrospective, non-interventional study was conducted that investigated the use of bDMARD in adult patients with RA in routine clinical practice. Data were extracted from the Optimising Patient Outcomes in Australian Rheumatology â Quality Use of Medicines Initiative database. Real-world effectiveness was measured using the 28-joint disease activity score (DAS28) and clinical disease activity index (CDAI) by treatment group at baseline, weeks 12 and 24. Results: A total of 2970 patients was included with a median (minâmax) age of 60.0 (19.0â94.0) years and median (minâmax) duration of RA before first bDMARD treatment of 6.0 (0.2â58.3) years. A total of 1177 patients received more than one bDMARD during the analysis period of 1 January 1997 to 15 August 2015. Patients had 4922 treatment âepisodesâ (defined as a cycle of continuous individual bDMARD prescribing in a single patient). Patients received a mean (SD) of 1.7 (1.0) episodes of treatment with median (minâmax) treatment duration of 0.7 (0â11.8) years; median treatment duration was higher with the first treatment episode. bDMARD were most commonly initiated in combination with methotrexate (73.9% of episodes) and least commonly as monotherapy (9.9% of episodes). Median (minâmax) baseline DAS28 decreased from 5.3 (0â8.7) with the first bDMARD to 3.7 (0â8.8) with the second. Median baseline CDAI similarly decreased. Conclusions: Patients tended to persist longer on their first bDMARD treatment. bDMARD as monotherapy or in combination appear to be accepted treatment strategies in the real worl
The CEDAR Study: A longitudinal study of the clinical effects of conventional DMARDs and biologic DMARDs in Australian rheumatology practice
Objectives. To observe the choices of conventional disease modifying antirheumatic drugs (cDMARDs) and biologic DMARDs (bDMARDs) in the management of rheumatoid arthritis (RA) in Australian routine clinical practice, to assess treatment survival and determine the effect of cDMARDs/bDMARDs on disease activity. Methods. Routinely collected, deidentified clinical data was sourced from 20 Australian rheumatology practices. RA patients aged â„18 years, who had received cDMARDs/bDMARDs and a recorded subsequent visit, were included. A linear mixed model was used to determine the change over time and the percentage reduction in disease activity was summarized. Results. 12,526 RA patients were included: 72% females, mean age 62 years. cDMARDs and bDMARDs were used in 92% and 30% of patients, respectively. The most commonly prescribed cDMARD was methotrexate (76% patients); median time to stopping treatment was 337 months [95% CI: 279âND]. Etanercept was the most commonly prescribed bDMARD (12% patients); median time to stopping treatment was 79 months [95% CI: 57â93]. Of 5,341 patients with a first change in medication (cDMARD or bDMARD), 87% had therapy escalation and 13% deescalation. Reduction in DAS28-ESR, 6-month post-DMARDs initiation ranged from 3%, adalimumab, to 14%, leflunomide and tocilizumab. Conclusions. In this large Australian cohort of unselected community RA patients, the choices of cDMARDs/bDMARDs are aligned with current international guidelinesThis work was supported by Roche Products Pty Limited
(Australia)
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