186 research outputs found
Better than Expected or as Bad as You Thought? The Neurocognitive Development of Probabilistic Feedback Processing
Learning from feedback lies at the foundation of adaptive behavior. Two prior neuroimaging studies have suggested that there are qualitative differences in how children and adults use feedback by demonstrating that dorsolateral prefrontal cortex (DLPFC) and parietal cortex were more active after negative feedback for adults, but after positive feedback for children. In the current study we used functional magnetic resonance imaging (fMRI) to test whether this difference is related to valence or informative value of the feedback by examining neural responses to negative and positive feedback while applying probabilistic rules. In total, 67 healthy volunteers between ages 8 and 22 participated in the study (8â11âyears, n = 18; 13â16âyears, n = 27; 18â22âyears, n = 22). Behavioral comparisons showed that all participants were able to learn probabilistic rules equally well. DLPFC and dorsal anterior cingulate cortex were more active in younger children following positive feedback and in adults following negative feedback, but only when exploring alternative rules, not when applying the most advantageous rules. These findings suggest that developmental differences in neural responses to feedback are not related to valence per se, but that there is an age-related change in processing learning signals with different informative value
Computational neuroscience across the lifespan: Promises and pitfalls
In recent years, the application of computational modeling in studies on age-related changes in decision making and learning has gained in popularity. One advantage of computational models is that they provide access to latent variables that cannot be directly observed from behavior. In combination with experimental manipulations, these latent variables can help to test hypotheses about age-related changes in behavioral and neurobiological measures at a level of specificity that is not achievable with descriptive analysis approaches alone. This level of specificity can in turn be beneficial to establish the identity of the corresponding behavioral and neurobiological mechanisms. In this paper, we will illustrate applications of computational methods using examples of lifespan research on risk taking, strategy selection and reinforcement learning. We will elaborate on problems that can occur when computational neuroscience methods are applied to data of different age groups. Finally, we will discuss potential targets for future applications and outline general shortcomings of computational neuroscience methods for research on human lifespan development
Social information use in adolescents with conduct problems and varying levels of callousâunemotional traits
BACKGROUND: Adolescents with conduct problems (CP) are characterised by difficulties with social relationships and display atypical social cognition, such as when interpreting emotional expressions or engaging in social problem-solving. One important aspect of social cognition that warrants investigation is the degree to which these adolescents factor others' views into their already held beliefs, and strategies used to do so. Effective social information use enables attunement to social environment, cooperation, and social problem-solving. Difficulties in this regard could contribute to problems in social interactions in adolescents with CP, and may vary with adolescents' high (CP/HCU) versus low levels of callous-unemotional traits (CP/LCU). METHODS: We compared social information use in boys (11â16 years) with CP/HCU (n = 32), CP/LCU (n = 31) and typically developing (TD) peers (n = 45), matched for IQ. Participants provided estimates of numbers of animals on a screen, saw another adolescent's estimate, and could adjust their initial estimate. We compared two aspects of social information use: (1) degree of adjustment of initial estimate towards another's estimate and (2) strategy use when adjusting estimates. RESULTS: Degree of adjustment towards another's estimate did not vary across groups, but strategy use did. Adolescents with CP/LCU compromised less following social information than TD peers. CONCLUSIONS: Findings suggest that while adolescents with CP are able to take social information into account, those with CP/LCU use this information in a way that differs from other groups and could be less efficient. This warrants further systematic investigation as it could represent a target for behaviour management strategies. Overall, this study highlights the need for more research delineating the social-cognitive profile of adolescents with CP/LCU
Social Learning and Preferences in Adolescents With Conduct Problems and Varying Levels of Callous-Unemotional Traits
Objective:
Learning to successfully navigate the social world, in particular when to trust others and how to work together with them, is crucial to well-adjusted social development. This is especially the case during adolescence, when individuals are undergoing significant biological and social changes. Adolescents with conduct problems (CP) tend to have difficulties in social relationships, and display aggressive behaviours as well as reduced cooperation with others. This pattern appears to be particularly pronounced in adolescents with CP and elevated callous-unemotional traits (CP/HCU). However, very little is currently known about the mechanisms which might drive reduced cooperative behaviours in adolescent CP, and whether these differ for those with high vs. low levels of CU traits.//
Method:
We used a series of economic games to assess how adolescents with CP/HCU (n = 46), CP and lower levels of CU traits (CP/LCU) (n = 46), and typically developing adolescents (TD) (n = 59) interacted with social (human) and non-social (computer) partners that varied in their degree of cooperation (trustworthy vs untrustworthy and friendly vs unfriendly), and whether this related to group differences in social preferences (aversion to inequality) and prior beliefs.//
Results:
Adolescents with CP (both HCU and LCU) had more difficulty than TD adolescents in differentiating between trustworthy and untrustworthy social environments in our task. Adolescents with CP/LCU also had more difficulty coordinating with friendly and unfriendly social partners to produce rewarding outcomes than TD adolescents. Surprisingly, we saw no relationship between participantsâ inequality aversion or prior beliefs and social learning in our games.//
Conclusion:
These findings indicate that, under controlled experimental conditions, adolescents with CP have more difficulty learning to differentiate between social environments that vary in cooperation - particularly adolescents with CP/LCU. These findings were not explained by inequality aversion or prior beliefs. Our findings also raise important questions regarding methods used to understand the mechanisms underlying social behaviors in adolescents with CP
Increased susceptibility to proactive interference in adults with dyslexia?
Recent findings show that people with dyslexia have an impairment in serial-order memory. Based on these findings, the present study aimed to test the hypothesis that people with dyslexia have difficulties dealing with proactive interference (PI) in recognition memory. A group of 25 adults with dyslexia and a group of matched controls were subjected to a 2-back recognition task, which required participants to indicate whether an item (mis)matched the item that had been presented 2 trials before. PI was elicited using lure trials in which the item matched the item in the 3-back position instead of the targeted 2-back position. Our results demonstrate that the introduction of lure trials affected 2-back recognition performance more severely in the dyslexic group than in the control group, suggesting greater difficulty in resisting PI in dyslexia.Peer reviewedFinal Accepted Versio
Peer learning and cultural evolution
In this article, we integrate cultural evolutionary theory with empirical research from developmental psychology, cultural anthropology, and primatology to explore the role of peer learning in the development of complex instrumental skills and behavioral norms. We show that instrumental imitation, contingent teaching, generative collaboration, and selective copying contribute to domain-specific transmission of knowledge between peers. Stages of development and characteristics inherent to the learner and model influence how and when children learn from each other. Peer learning is persistent across societies despite cultural beliefs that favor adultâchild transmission in some settings. Comparative research hints at the possibility that children's greater motivation to interact with and learn from each other may set humans apart from other primates. We conclude by outlining avenues for future research, including how individual characteristics and developmental changes in social networks, motivation, and cognition may contribute to cultural evolution.</p
Collaborative roles of Temporoparietal Junction and Dorsolateral Prefrontal Cortex in Different Types of Behavioural Flexibility
Behavioural flexibility is essential for everyday life. This involves shifting attention between different perspectives. Previous studies suggest that flexibility is mainly subserved by the dorsolateral prefrontal cortex (DLPFC). However, although rarely emphasized, the temporoparietal junction (TPJ) is frequently recruited during flexible behaviour. A crucial question is whether TPJ plays a role in different types of flexibility, compared to its limited role in perceptual flexibility. We hypothesized that TPJ activity during diverse flexibility tasks plays a common role in stimulus-driven attention-shifting, thereby contributing to different types of flexibility, and thus the collaboration between DLPFC and TPJ might serve as a more appropriate mechanism than DLPFC alone. We used fMRI to measure DLPFC/TPJ activity recruited during moral flexibility, and examined its effect on other domains of flexibility (economic/perceptual). Here, we show the additional, yet crucial role of TPJ: a combined DLPFC/TPJ activity predicted flexibility, regardless of domain. Different types of flexibility might rely on more basic attention-shifting, which highlights the behavioural significance of alternatives.Peer reviewe
Reporting road traffic serious injuries in Europe. Guidelines from the SafetyCube project (H2020)
Reporting road traffic serious injuries in Europe. Guidelines from the SafetyCube project (H2020
Late onset cardiomyopathy as presenting sign of ATTR A45G amyloidosis caused by a novel TTR mutation (p.A65G)
Objective: The clinical description of a novel TTR genemutation characterized by a late onset amyloid cardiomyopathy.Methods and Results: A 78-year-old man of Dutch origin with recent surgeryforbilateral carpal tunnel syndrome(CTS) was admitted to our hospital because of heart failure with preserved ejection fraction (55%). Cardiac ultrasound showed thickened biventricular walls, and cardiac magnetic resonance imaging also showed late gadolinium enhancement. Early signs of a polyneuropathy were found by neurophysiological testing. A few months later, his 72year- old sister was admitted to an affiliated hospital because of heart failure caused by a restrictive cardiomyopathy. In both patients, a subcutaneous abdominal fat aspirate was stained with Congo red and DNA was analyzed by direct sequencing of exons 1 to 4 of the transthyretin (TTR) gene. Both fat aspirates revealed transthyretin-derived (ATTR) amyloid. Tc-99m-diphosphonate scintigraphy further confirmed cardiac ATTR amyloidosis in the male patient. DNA analysis of both patients showed a novel TTR mutation c.194C>G that encodes for the gene product TTR (p.A65G) ending up as themature protein TTR A45G. The 56-year-old daughter of themale patient had the same TTR mutation. A full diagnostic workup did not reveal any signs of amyloidosis yet.Conclusions: A novel amyloidogenic TTRmutation was found in a Dutch family. The clinical presentation of ATTR A45G amyloidosis in the affected family members was heart failure due to a late-onset cardiomyopathy. The systemic nature of this disease was reflected by bilateral CTS and by early signs of a polyneuropathy in the index patient.</p
Underlying molecular mechanisms of DIO2 susceptibility in symptomatic osteoarthritis
Objectives: To investigate how the genetic susceptibility gene DIO2 confers risk to osteoarthritis (OA) onset in humans and to explore whether counteracting the deleterious effect could contribute to novel therapeutic approaches. Methods: Epigenetically regulated expression of DIO2 was explored by assessing methylation of positional CpG-dinucleotides and the respective DIO2 expression in OA-affected and macroscopically preserved articular cartilage from end-stage OA patients. In a human in vitro chondrogenesis model, we measured the effects when thyroid signalling during culturing was either enhanced (excess T3 or lentiviral induced DIO2 overexpression) or decreased (iopanoic acid). Results: OA-related changes in methylation at a specific CpG dinucleotide upstream of DIO2 caused significant upregulation of its expression (Ă=4.96; p=0.0016). This effect was enhanced and appeared driven specifically by DIO2 rs225014 risk allele carriers (Ă=5.58, p=0.0006). During in vitro chondrogenesis, DIO2 overexpression resulted in a significant reduced capacity of chondrocytes to deposit extracellular matrix (ECM) components, concurrent with significant induction of ECM degrading enzymes (ADAMTS5, MMP13) and markers of mineralisation (ALPL, COL1A1). Given their concurrent and significant upregulation of expression, this process is likely mediated via HIF-2a/RUNX2 signalling. In contrast, we showed that inhibiting deiodinases during in vitro chondrogenesis contributed to prolonged cartilage homeostasis as reflected by significant increased deposition of ECM components and attenuated upregulation of matrix degrading enzymes. Conclusions: Our findings show how genetic variation at DIO2 could confer risk to OA and raised the possibility that counteracting thyroid signalling may be a novel therapeutic approach
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