18 research outputs found

    Should I stay or should I go? How local-global implicit temporal expectancy shapes proactive motor control: An hdEEG study

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    In this study, we investigated the effect of global temporal prediction on the brain capability to implicitly adjust proactive motor control. We used the Dynamic Temporal Prediction (DTP), in which local and global predictions of an imperative stimulus were manipulated by using different stimulus-onset asynchronies (SOAs), presented with several distribution probabilities. At a behavioural level, the results show a performance adjustment (reaction time decrease) depending on the implicit use of global prediction. At a neurophysiological level, three separate computational steps underlying motor control were investigated. First, the expectancy implementation was associated with global probability-dependent contingent negative variation (CNV) modulation supported by the recruitment of a frontoparietal network involving the anterior cingulate, the left intraparietal sulcus, the occipital, and the premotor areas. Second, the response implementation was modulated by the global prediction fostering stimulus processing (P3 increase) at the motor response level, as suggested by both oscillatory (beta desynchronization), as well as source analysis (frontal cortical network). Third, the expectancy violation lead to a negativity increase (omission-detection potential) time locked to the global rule violation and additionally, to delta and theta power increase interpreted as inhibitory control and rule violation detection, respectively. The expectancy violation further engaged a left lateralized network including the temporal parietal junction (TPJ) and the motor cortex, suggesting involvement of attentional reorienting and a motor adjustment. Finally, these findings provide new insights on the neurocognitive mechanisms underlying proactive motor control, suggesting an overlapping between implicit and explicit processes

    The Effect of Probabilistic Context on Implicit Temporal Expectations in Down Syndrome

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    One of the most important sources of predictability that human beings can exploit to create an internal representation of the external environment is the ability to implicitly build up subjective statistics of events\u2019 temporal structure and, consequently, use this knowledge to prepare for future actions. Stimulus expectancy can be subjectively shaped by hierarchically nested sources of prediction, capitalizing on either local or global probabilistic rules. In order to better understand the nature of local-global proactive motor control in Down Syndrome, in the present study a group of participants with Down Syndrome (DS group; n = 28; mean age 29.5 \ub1 13 years; range 10\u201354) and a group of typically developing participants matched by either gender or mental age (TD-MA group; n = 28; 5.6 \ub1 1 years; range 4\u20138) were administered a novel motor preparation task, defined as the Dynamic Temporal Prediction (DTP) task. In the DTP, the temporal preparation to imperative stimuli is implicitly shaped by the local increase of expectancy. This is manipulated trial-by-trial as a function of the preparatory foreperiod interval (Stimulus-Onset Asynchrony or SOA). In addition, temporal preparation can be also implicitly adjusted as a function of global predictive context, so that a block-wise SOA-distribution bias toward a given preparatory interval might determine a high-order source of expectancy, with functional consequences on proactive motor control adjustment. Results showed that in both groups motor preparation was biased by temporal expectancy when this was locally manipulated within-trials. By contrast, only the TD-MA group was sensitive to global rule changes: only in this cohort was behavioral performance overall impacted by the SOA probabilistic distribution manipulated between-blocks. The evidence of a local-global dissociation in DS suggests that the use of flexible cognitive mechanisms to implicitly extract high-order probabilistic rules in order to build-up an internal model of the temporal properties of events is disrupted in this developmental disorder. Moreover, since the content of the information to be processed in the DTP task was neither verbal nor spatial, we suggest that atypical global processing in Down Syndrome is a domain-general rather than specific aspect characterizing the cognitive profile of this population

    The influence of visual illusion perception on numerosity estimation could be evolutionarily conserved: exploring the numerical Delboeuf illusion in humans (Homo sapiens) and fish (Poecilia reticulata)

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    Discriminating between different quantities is an essential ability in daily life that has been demonstrated in a variety of non-human vertebrates. Nonetheless, what drives the estimation of numerosity is not fully understood, as numerosity intrinsically covaries with several other physical characteristics. There is wide debate as to whether the numerical and spatial abilities of vertebrates are processed by a single magnitude system or two different cognitive systems. Adopting a novel approach, we aimed to investigate this issue by assessing the interaction between area size and numerosity, which has never been conceptualized with consideration for subjective experience in non-human animals. We examined whether the same perceptual biases underlying one of the best-known size illusions, the Delboeuf illusion, can be also identified in numerical estimation tasks. We instructed or trained human participants and guppies, small teleost fish, to select a target numerosity (larger or smaller) of squares between two sets that actually differed in their numerosity. Subjects were also presented with illusory trials in which the same numerosity was presented in two different contexts, against a large and a small background, resembling the Delboeuf illusion. In these trials, both humans and fish demonstrated numerical biases in agreement with the perception of the classical version of the Delboeuf illusion, with the array perceived as larger appearing more numerous. Thus, our results support the hypothesis of a single magnitude system, as perceptual biases that influence spatial decisions seem to affect numerosity judgements in the same way

    Should I stay or should I go? How local-global implicit temporal expectancy shapes proactive motor control: An hdEEG study

    No full text
    In this study, we investigated the effect of global temporal prediction on the brain capability to implicitly adjust proactive motor control. We used the Dynamic Temporal Prediction (DTP), in which local and global predictions of an imperative stimulus were manipulated by using different stimulus-onset asynchronies (SOAs), presented with several distribution probabilities. At a behavioural level, the results show a performance adjustment (reaction time decrease) depending on the implicit use of global prediction. At a neurophysiological level, three separate computational steps underlying motor control were investigated. First, the expectancy implementation was associated with global probability-dependent contingent negative variation (CNV) modulation supported by the recruitment of a frontoparietal network involving the anterior cingulate, the left intraparietal sulcus, the occipital, and the premotor areas. Second, the response implementation was modulated by the global prediction fostering stimulus processing (P3 increase) at the motor response level, as suggested by both oscillatory (beta desynchronization), as well as source analysis (frontal cortical network). Third, the expectancy violation lead to a negativity increase (omission-detection potential) time locked to the global rule violation and additionally, to delta and theta power increase interpreted as inhibitory control and rule violation detection, respectively. The expectancy violation further engaged a left lateralized network including the temporal parietal junction (TPJ) and the motor cortex, suggesting involvement of attentional reorienting and a motor adjustment. Finally, these findings provide new insights on the neurocognitive mechanisms underlying proactive motor control, suggesting an overlapping between implicit and explicit processes

    Forgetting curves and testing effect in an adaptive learning and assessment system

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    In the context of an adaptive learning and assessment system, ALEKS, we examine aspects of forgetting and aspects of a \u2018testing effect\u2019 (in which the act of simply being presented a problem in an assessment seems to assist in the learning process). Using a dataset consisting of over six million ALEKS assessments, we first look at the trend of student responses over the course of the assessment, finding little evidence for such a testing effect. We then refine our approach by looking at cases in which a question is repeated in an assessment; repeats are possible because some question is always chosen at random in an assessment for data-collection purposes. We find evidence of a testing effect for higher-performing students; for lower-performing students, we find a decreased willingness to attempt an answer the second time a problem is presented. Then, turning to forgetting, we find that the content representing the \u201chigh points\u201d of a student\u2019s learning sees a more precipitous drop in the student\u2019s memory than does other content (perhaps because the \u201chigh point\u201d skills and concepts may not have been practiced or developed much since the original learning event). Consequences and possible improvements for the ALEKS system, and also a brief comparison to recent work in the modeling of forgetting, are mentioned

    ATS-PD: An Adaptive Testing System for Psychological Disorders

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    The clinical assessment of mental disorders can be a time-consuming and error-prone procedure, consisting of a sequence of diagnostic hypothesis formulation and testing aimed at restricting the set of plausible diagnoses for the patient. In this article, we propose a novel computerized system for the adaptive testing of psychological disorders. The proposed system combines a mathematical representation of psychological disorders, known as the “formal psychological assessment,” with an algorithm designed for the adaptive assessment of an individual’s knowledge. The assessment algorithm is extended and adapted to the new application domain. Testing the system on a real sample of 4,324 healthy individuals, screened for obsessive-compulsive disorder, we demonstrate the system’s ability to support clinical testing, both by identifying the correct critical areas for each individual and by reducing the number of posed questions with respect to a standard written questionnaire

    The mediating role of scientifical-medical satisfaction between COVID-19 conspiracy beliefs and vaccine confidence: a two-waves structural equation model

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    Vaccine confidence has emerged as one of the most relevant psychological factors implied in the worldwide affecting the fight against COVID-19—as well as public trust in doctors, medicine, and science. Indeed, the vaccine confidence is crucial to maximize the trust in vaccines and their use for prevention, with several implications for public health. This study aimed to analyse the relationships among between vaccine confidence, conspiracy beliefs about COVID-19, and satisfaction with science and medicine in handling the COVID-19 pandemic. A longitudinal observational survey was administered to a convenience sample (n = 544; mean age 52.76 y.o., SD = 15.11; females 46.69%) from the Italian general population. A two-waves mediation model—a structural equation model technique—was used. The survey was part of a larger international project (https://osf.io/qy65b/). The model highlighted that the conspiracy beliefs about COVID-19 had a negative effect on the satisfaction with medicine and science (ÎČ = − 0.13, se = 0.03, p <.001). The latter, in turn, had a positive effect on vaccine confidence (ÎČ = 0.10, se =.05, p <.001). Interestingly, the effect of conspiracy beliefs on vaccine confidence was completely mediated by the scientifical-medical satisfaction (ÎČ = − 0.02, se = 0.01, p <.05). These results highlight how the scientifical-medical satisfaction can fully mediate the relationship between conspiracy beliefs about COVID-19 and vaccine confidence. These findings about vaccine hesitancy and confidence and disclose have implications for psychological and social interventions that could promote vaccine confidence by targeting the satisfaction with science and medicine

    Emergency department and early detection of adolescents and young adults at risk of developing mental disorders: An exploratory study

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    The objective of this study is to assess the potential role of Emergency Department (ED) for early detection of mental disorders. Two cohorts (6,759 subjects aged 14 to 24 accessing ED, 165 subjects with mental disorders) were matched by ID and merged. Primary outcome was the proportion of individuals accessing ED before receiving a diagnosis of mental disorder in Mental Health Service (MHS). Secondary outcomes were age of first access to ED in subjects later accessing to MHS, and time from first ED access to receiving a diagnosis of mental disorder at MHS. We assessed whether gender, severity of ED presentation, and number of ED accesses predicted primary outcome. Almost half of individuals who later developed mental disorders (49.7%) accessed ED before access to MHS. Mean age of first ED contact among those later accessing to MHS was 17.34 (2.1), and ED access preceded access to MHS by 3.68 (2.11) years. Gender and severity of ED presentation were not associated with the access to MHS, while higher number of ED accesses was associated with later access to MHS (OR range: 1.17-1.36, p<0.05). Despite its limitations, the present study suggests ED might represent a contact point for individuals who later access to MHS. Future early detection programs should involve ED in their outreach and screening approaches. Additional studies are needed to assess if subjects earlier accessing to ED are at risk-of-developing or already suffer from a mental disorder, and to validate screening instruments specifically designed for ED

    Moral Orientation Guilt Scale (MOGS): Development and validation of a novel guilt measurement

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    Guilt emerges as the emotional result of a conflict between our behavior and internalized morality. Since morality is best conceptualized as a multidimensional construct, guilt results in different phenomena depending on the moral values internalized by the "guilty". Indeed, mounting evidence supports the distinction between guilt feelings emerging from deontological morality and guilt feelings emerging from altruistic morality. Most measures fail to consider moral orientation when assessing guilt. Our aim was to develop a reliable and valid tool, able to independently measure different types of guilt feelings. We presented the 17-items Moral Orientation Guilt Scale (MOGS) to a large subclinical sample, along with other questionnaires. Analyses included measures of classical test theory and innovative techniques of network analysis. This cross-validation approach pointed at four factors: "Moral Norm Violation", "Moral Dirtiness", "Empathy" and "Harm". Results suggested MOGS good reliability and a strong construct and convergent validity. Importantly, "Moral Norm Violation" and "Moral Dirtiness" scores were positively correlated with disgust sensitivity, supporting the link between disgust and deontological guilt. Differently, "Harm" scores were negatively correlated with disgust sensitivity scores, in line with the notion that altruism and disgust possibly evolved as part of contrasting motivational systems
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