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91.
The development of the ability to anticipate—as manifested by preparatory actions and neural activation related to the expectation of an upcoming stimulus—may play a key role in the ontogeny of cognitive skills more broadly. This preregistered study examined anticipatory brain potentials and behavioral responses (reaction time; RT) to anticipated target stimuli in relation to individual differences in the ability to use goals to direct action (as indexed by measures of executive function; EF). A cross-sectional investigation was conducted in 40 adults (aged 18–25 years) and 40 children (aged 6–8 years) to examine the association of changes in the amplitude of modality-specific alpha-range rhythms in the electroencephalogram (EEG) during anticipation of lateralized visual, tactile, or auditory stimuli with inter- and intraindividual variation in RT and EF. Children and adults exhibited contralateral anticipatory reductions in the mu rhythm and the visual alpha rhythm for tactile and visual anticipation, respectively, indicating modality and spatially specific attention allocation. Variability in within-subject anticipatory alpha lateralization (the difference between contralateral and ipsilateral alpha power) was related to single-trial RT. This relation was more prominent in adults than in children, and was not apparent for auditory stimuli. Multilevel models indicated that interindividual differences in anticipatory mu rhythm lateralization contributed to the significant association with variability in EF, but this was not the case for visual or auditory alpha rhythms. Exploratory microstate analyses were undertaken to cluster global field power (GFP) into a distribution-free temporal analysis examining developmental differences across samples and in relation to RT and EF. Anticipation is suggested as a developmental bridge construct connecting neuroscience, behavior, and cognition, with anticipatory EEG oscillations being discussed as quantifiable and potentially malleable indicators of stimulus prediction.  相似文献   
92.
When teaching infants new actions, parents tend to modify their movements. Infants prefer these infant-directed actions (IDAs) over adult-directed actions and learn well from them. Yet, it remains unclear how parents’ action modulations capture infants’ attention. Typically, making movements larger than usual is thought to draw attention. Recent findings, however, suggest that parents might exploit movement variability to highlight actions. We hypothesized that variability in movement amplitude rather than higher amplitude is capturing infants’ attention during IDAs. Using EEG, we measured 15-month-olds’ brain activity while they were observing action demonstrations with normal, high, or variable amplitude movements. Infants’ theta power (4–5 Hz) in fronto-central channels was compared between conditions. Frontal theta was significantly higher, indicating stronger attentional engagement, in the variable compared to the other conditions. Computational modelling showed that infants’ frontal theta power was predicted best by how surprising each movement was. Thus, surprise induced by variability in movements rather than large movements alone engages infants’ attention during IDAs. Infants with higher theta power for variable movements were more likely to perform actions successfully and to explore objects novel in the context of the given goal. This highlights the brain mechanisms by which IDAs enhance infants’ attention, learning, and exploration.  相似文献   
93.
Animal Cognition - The alarm calls of nonhuman primates are occasionally cited as functionally equivalent to lexical word meaning in human language. Recently, however, it has become increasingly...  相似文献   
94.
The COVID-19 pandemic necessitated abrupt and substantial changes in daily life, and public health strategies intended to protect physical health can negatively affect mental health and well-being, especially for individuals with pre-existing mental health challenges. For this study, we surveyed a sample of clients (N = 94) in the summer of 2020 from a community mental health clinic in the northeast United States. A mixed-methods, concurrent triangulation design was used to (a) identify client subgroups on indicators of mental health (i.e. anxious and depressive symptoms) and emotional, psychological, and social well-being using latent profile analysis (LPA), and (b) within these subgroups, examine qualitative, thematic patterns in self-described challenges, benefits and learning related to the pandemic. The LPA revealed five distinct subgroups with various levels of symptoms and well-being, including Stagnant (moderate symptoms/moderate well-being), Languishing (high symptoms/low well-being), Flourishing (low symptoms, high well-being), Fortitudinous (high symptoms, moderate well-being) and Mobilized (moderate symptoms, high well-being). These divergent subgroups support the need to conceptualise mental health symptoms apart from well-being and assess for heterogeneous constellations of such constructs among psychotherapy clients. Thematic analysis offered additional insight into pandemic experiences within each subgroup, including attention to psychological, emotional, behavioural/lifestyle, relational, physical and ecological/contextual dimensions of self-experience, as well as the ways clients had adjusted to the pandemic's circumstances. Findings support nuanced conceptualisations of positive mental health and offer insight into coping and adaptation during this public health crisis.  相似文献   
95.
To date, virtually no studies have examined toddlers' non-response in developmental tasks. This study investigates data from 3667 toddlers to address (1) whether two aspects of non-response (completion and engagement) are separable, (2) how stable these aspects are from ages two to three, (3) how non-response relates to background characteristics, and (4) whether non-response at ages two and three predicts early academic skills at age six. Structural equation modelling shows that completion and engagement are separable constructs, relatively stable across age, and related to several background characteristics. Especially engagement predicts later academic performance. Results show that non-response in behavioural tasks in toddlers is not random, increasing the likelihood of sampling bias and lack of generalizability in developmental studies.  相似文献   
96.
97.
Conspiracy beliefs have been studied mostly through cross-sectional designs. We conducted a five-wave longitudinal study (N = 376; two waves before and three waves after the 2020 American presidential elections) to examine if the election results influenced specific conspiracy beliefs and conspiracy mentality, and whether effects differ between election winners (i.e., Biden voters) versus losers (i.e., Trump voters) at the individual level. Results revealed that conspiracy mentality kept unchanged over 2 months, providing first evidence that this indeed is a relatively stable trait. Specific conspiracy beliefs (outgroup and ingroup conspiracy beliefs) did change over time, however. In terms of group-level change, outgroup conspiracy beliefs decreased over time for Biden voters but increased for Trump voters. Ingroup conspiracy beliefs decreased over time across all voters, although those of Trump voters decreased faster. These findings illuminate how specific conspiracy beliefs are, and conspiracy mentality is not, influenced by an election event.  相似文献   
98.
The social identity theory of leadership is a unique perspective in leadership research in capturing how responses to leadership are informed by how the leader is perceived through the lens of the group identity shared by leaders and followers. I review the theory in broad strokes to make the case that a particularly valuable future development of the theory is to complement the theory's emphasis on group member (follower) perceptions of leader group prototypicality, the extent to which the leader is perceived to embody the group identity, with theory and evidence speaking to leader agency in influencing such perceptions.  相似文献   
99.
A model for the analysis of paired comparison data is presented which combines features of the BTL-model with features of the Unfolding model. The model is metric, mathematically tractable, and has an exact algebraic solution. Since it is multidimensional and allows for individual differences, it is thought to be more realistic for some choice situations than either the Thurstone model or the BTL-model. No claim is made that the present model will be appropriate for all conceivable choice situations. Rather, it is argued that the fact that it is explicitly falsifiable is a point in its favor.This work was supported by a grant of the United States Public Health Service (1 R03 MH19139 01 MSM) and a David Ross (XR) grant of the Purdue Research Foundation (PRF 2132), both of which are gratefully acknowledged. We also owe thanks to Dr. Terry Cooper, whose careful scrutiny of an earlier draft of this paper allowed us to reduce the number of errors from n to n-1.  相似文献   
100.
Some relations between maximum likelihood factor analysis and factor indeterminacy are discussed. Bounds are derived for the minimum average correlation between equivalent sets of correlated factors which depend on the latent roots of the factor intercorrelation matrix . Empirical examples are presented to illustrate some of the theory and indicate the extent to which it can be expected to be relevant in practice.  相似文献   
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