396 research outputs found

    Theory of mind and decision science: Towards a typology of tasks and computational models

    Get PDF
    The ability to form a Theory of Mind (ToM), i.e., to theorize about others’ mental states to explain and predict behavior in relation to attributed intentional states, constitutes a hallmark of human cognition. These abilities are multi-faceted and include a variety of different cognitive sub-functions. Here, we focus on decision processes in social contexts and review a number of experimental and computational modeling approaches in this field. We provide an overview of experimental accounts and formal computational models with respect to two dimensions: interactivity and uncertainty. Thereby, we aim at capturing the nuances of ToM functions in the context of social decision processes. We suggest there to be an increase in ToM engagement and multiplexing as social cognitive decision-making tasks become more interactive and uncertain. We propose that representing others as intentional and goal directed agents who perform consequential actions is elicited only at the edges of these two dimensions. Further, we argue that computational models of valuation and beliefs follow these dimensions to best allow researchers to effectively model sophisticated ToM-processes. Finally, we relate this typology to neuroimaging findings in neurotypical (NT) humans, studies of persons with autism spectrum (AS), and studies of nonhuman primates

    The effect of virtual mindfulness-based interventions on sleep quality: A systematic review of randomized controlled trials

    Get PDF
    PURPOSE OF REVIEW: We summarized peer-reviewed literature investigating the effect of virtual mindfulness-based interventions (MBIs) on sleep quality. We aimed to examine the following three questions: (1) do virtual MBIs improve sleep quality when compared with control groups; (2) does the effect persist long-term; and (3) is the virtual delivery method equally feasible compared to the in-person delivery method? RECENT FINDINGS: Findings suggest that virtual MBIs are equivalent to evidence-based treatments, and to a limited extent, more effective than non-specific active controls at reducing some aspects of sleep disturbance. Overall, virtual MBIs are more effective at improving sleep quality than usual care controls and waitlist controls. Studies provide preliminary evidence that virtual MBIs have a long-term effect on sleep quality. Moreover, while virtual MBI attrition rates are comparable to in-person MBI attrition rates, intervention adherence may be compromised in the virtual delivery method. This review highlights virtual MBIs as a potentially effective alternative to managing sleep disturbance during pandemic-related quarantine and stay-at-home periods. This is especially relevant due to barriers of accessing in-person interventions during the pandemic. Future studies are needed to explore factors that influence adherence and access to virtual MBIs, with a particular focus on diverse populations

    How does over-squashing affect the power of GNNs?

    Get PDF
    Graph Neural Networks (GNNs) are the state-of-the-art model for machine learning on graph-structured data. The most popular class of GNNs operate by exchanging information between adjacent nodes, and are known as Message Passing Neural Networks (MPNNs). While understanding the expressive power of MPNNs is a key question, existing results typically consider settings with uninformative node features. In this paper, we provide a rigorous analysis to determine which function classes of node features can be learned by an MPNN of a given capacity. We do so by measuring the level of pairwise interactions between nodes that MPNNs allow for. This measure provides a novel quantitative characterization of the so-called over-squashing effect, which is observed to occur when a large volume of messages is aggregated into fixed-size vectors. Using our measure, we prove that, to guarantee sufficient communication between pairs of nodes, the capacity of the MPNN must be large enough, depending on properties of the input graph structure, such as commute times. For many relevant scenarios, our analysis results in impossibility statements in practice, showing that over-squashing hinders the expressive power of MPNNs. Our theory also holds for geometric graphs and hence extends to equivariant MPNNs on point clouds. We validate our analysis through extensive controlled experiments and ablation studies

    How does over-squashing affect the power of GNNs?

    Full text link
    Graph Neural Networks (GNNs) are the state-of-the-art model for machine learning on graph-structured data. The most popular class of GNNs operate by exchanging information between adjacent nodes, and are known as Message Passing Neural Networks (MPNNs). Given their widespread use, understanding the expressive power of MPNNs is a key question. However, existing results typically consider settings with uninformative node features. In this paper, we provide a rigorous analysis to determine which function classes of node features can be learned by an MPNN of a given capacity. We do so by measuring the level of pairwise interactions between nodes that MPNNs allow for. This measure provides a novel quantitative characterization of the so-called over-squashing effect, which is observed to occur when a large volume of messages is aggregated into fixed-size vectors. Using our measure, we prove that, to guarantee sufficient communication between pairs of nodes, the capacity of the MPNN must be large enough, depending on properties of the input graph structure, such as commute times. For many relevant scenarios, our analysis results in impossibility statements in practice, showing that over-squashing hinders the expressive power of MPNNs. We validate our theoretical findings through extensive controlled experiments and ablation studies

    Vascular smooth muscle TRPC3 channels facilitate the inverse hemodynamic response during status epilepticus

    Get PDF
    Human status epilepticus (SE) is associated with a pathological reduction in cerebral blood flow termed the inverse hemodynamic response (IHR). Canonical transient receptor potential 3 (TRPC3) channels are integral to the propagation of seizures in SE, and vascular smooth muscle cell (VSMC) TRPC3 channels participate in vasoconstriction. Therefore, we hypothesize that cerebrovascular TRPC3 channels may contribute to seizure-induced IHR. To examine this possibility, we developed a smooth muscle-specific TRPC3 knockout (TRPC3smcKO) mouse. To quantify changes in neurovascular coupling, we combined laser speckle contrast imaging with simultaneous electroencephalogram recordings. Control mice exhibited multiple IHRs, and a limited increase in cerebral blood flow during SE with a high degree of moment-to-moment variability in which blood flow was not correlated with neuronal activity. In contrast, TRPC3smcKO mice showed a greater increase in blood flow that was less variable and was positively correlated with neuronal activity. Genetic ablation of smooth muscle TRPC3 channels shortened the duration of SE by eliminating a secondary phase of intense seizures, which was evident in littermate controls. Our results are consistent with the idea that TRPC3 channels expressed by cerebral VSMCs contribute to the IHR during SE, which is a critical factor in the progression of SE.Fil: Cozart, Michael A.. University of Arkansas for Medical Sciences; Estados UnidosFil: Phelan, Kevin D.. University of Arkansas for Medical Sciences; Estados UnidosFil: Wu, Hong. University of Arkansas for Medical Sciences; Estados UnidosFil: Mu, Shengyu. University of Arkansas for Medical Sciences; Estados UnidosFil: Birnbaumer, Lutz. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Rusch, Nancy J.. University of Arkansas for Medical Sciences; Estados UnidosFil: Zheng, Fang. University of Arkansas for Medical Sciences; Estados Unido

    ASAP: a resource for annotating, curating, comparing, and disseminating genomic data

    Get PDF
    ASAP is a comprehensive web-based system for community genome annotation and analysis. ASAP is being used for a large-scale effort to augment and curate annotations for genomes of enterobacterial pathogens and for additional genome sequences. New tools, such as the genome alignment program Mauve, have been incorporated into ASAP in order to improve display and analysis of related genomes. Recent improvements to the database and challenges for future development of the system are discussed. ASAP is available on the web at

    Predictors of survival in malignant tumors of the sternum

    Get PDF
    AbstractFrom 1930 to 1994, 54 patients with primary malignant tumors of the sternum were seen. Fifty patients were first seen with a mass, and one half of them also had pain in the sternal region. Two patients had no symptoms at presentation. Among 39 solid tumors were 26 chondrosarcomas, 10 osteosarcomas, 1 fibrosarcoma, 1 angiosarcoma, and 1 malignant fibrous histiocytoma. Of these, 25 were low-grade and 14 were high-grade tumors. Among 15 small cell tumors were 8 plasmacytomas, 6 malignant lymphomas, and 1 Ewing's sarcoma. Partial or subtotal sternectomy was done in 37 patients and total sternectomy in 3. Of the remaining 14 patients, 3 had local excision; 10 had external radiation or chemotherapy without operation, or both; and 1 had no treatment. All but one patient treated by wide resection ( N = 40) had some form of skeletal reconstruction of the chest wall defect. Thirty-one (78%) underwent repair with Marlex mesh, and in 25 this was combined with methyl methacrylate. The skin edges were closed per primum in 32 patients; 8 required muscle, omentum, or skin flaps. Resection in chondrosarcomas yielded a 5-year survival (Kaplan-Meier) of 80% (median follow-up, 17 years). The 5-year survival in osteosarcomas was 14%. Resection was curative in 64% of low-grade sarcomas but in only 7% of high-grade sarcomas. In small cell tumors, resection and radiation were helpful for local control; all failures were a result of distant metastases. We conclude that primary sarcomas of the sternum though uncommon are potentially curable by wide surgical excision. With rigid prostheses to repair the skeletal defects, the surgical complication rates are low. Overall survival after complete surgical resection is related to tumor histologic type and grade. (J THORAC CARDIOVASC SURG 1996;111:96-106
    • …
    corecore