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71.
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   
72.
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   
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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   
75.
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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Judgments of the acceptability of correct, word order reversed, and semantically anomalous sentences were elicited from 2- and 3-year-old children in a game played with hand puppets. All of the sentences used were simple imperatives and each child was asked to correct those he called wrong. Performance on the judgment task was correlated with each child's mean length of utterance and with his comprehension of reversible active and passive sentences. Only the linguistically most advanced children were able to make a significant number of appropriate judgments and corrections of reversed word order imperatives. Less developed children could appropriately judge and correct semantically anomalous but not incorrect word order imperatives. The importance of semantic as opposed to syntactic factors in children's judgments of the acceptability of sentences is stressed.This research was supported in part by PHS Grant HD-02908 from the National Institute of Child Health and Development. Roger Brown is the principal investigator.  相似文献   
78.
In the first of two experiments, it was demonstrated that an air puff elicited a reliable startle reflex in rats which showed no habituation over 50 trials. In the second study an attempt was made to measure an emotional response by recording startle reactions to the air puff during presentation of a presumed fear-eliciting CS. It was concluded that the air-puff-elicited startle reflex can be employed as an indirect measure of a hypothetical emotional response.  相似文献   
79.
The generation of satisfactory artificial speech involves a great variety of semantic, linguistic, and articulatory factors. Many of these complex elements are as yet unknown, and computers are used extensively for their investigation. An account of an on-line, interactive computer facility used for such research at Bell Laboratories is given. The use of this facility for exploring the duration and pitch correlates of stress in English sentences is described.  相似文献   
80.
Summary This paper expands a new hypothesis on the causal mechanisms underlying irrelevant behaviour. It begins with a critical summary of earlier theories which attempted to explain displacement activities, but failed to predict the consistency with which certain types of behaviour are shown in stressful situations by a variety of species. Behavioural and physiological studies suggest that these behaviour patterns are closely associated with the incipient activation of sleep. The functional significance of this link and some of the causal processes which may be responsible for it are discussed. Paradoxically, however, displacement activities occur when animals are in a state of high arousal. The concept of arousal is reconsidered in the light of information theory and assumed to be closely correlated with the information processing rate in the nervous system. The relationships between neural and autonomic arousal are considered in this context. It is argued that over-arousal may occur when information handling exceeds the limited channel capacity of the system, with a consequent loss of efficiency. It is pointed out that there are mechanisms capable of controlling the information influx into the brain, and it is hypothesized that they are tied up in a feedback mechanism which regulates arousal and which involves the activation of a de-arousal system, corresponding to the neurological sleep mechanism. Displacement activities are viewed as consequences of this regulatory activation of the sleep system. This hypothesis is then compared with existing theories of displacement and its relationship with them is discussed.
Zusammenfassung Die Arbeit erweitert eine neue Hypothese über die kausalen Mechanismen, die dem übersprungverhalten zugrunde liegen. Sie beginnt mit einer kritischen Übersicht der früher vorgeschlagenen Theorien und zeigt auf, daß diese nicht die Beständigkeit, mit der gewisse Verhaltensweisen von einer Anzahl von Tierarten in Stress-Situationen gezeigt werden, erklären. Verhaltens- und physiologische Studien deuten an, daß diese Verhaltensweisen in einem engen Zusammenhang mit einer partiellen Schlafaktivierung stehen. Die funktionelle Bedeutung dieses Zusammenhanges und die möglichen physiologischen Mechanismen, die dafür verantwortlich sein könnten, werden diskutiert. Paradoxerweise werden aber Übersprungsverhalten dann gezeigt, wenn sich Tiere in einem gesteigerten Wachzustand befinden. In diesem Zusammenhang wird das Arousal-Konzept im Lichte der Informationstheorie neu beleuchtet und es wird angenommen, daß der Arousal-Zustand eines Tieres im engen Zusammenhang mit der jeweiligen Informationsverarbeitungsrate im Nervensystem steht. Die Verhältnisse zwischen neuralem und autonomischen Arousal werden diskutiert. Es wird vorgeschlagen, daß sich Überarousal dann einstellt, wenn die Informationsverarbeitungsrate die Kanalkapazität des Systems übersteigt mit einem sich daraus ergebenen Wirkungsgradverlust. Es wird darauf hingewiesen, daß es Mechanismen gibt, die den Informationsfluß in das Gehirn regeln und angenommen, daß diese innerhalb eines Rückkopplungssystems funktionieren, welches Arousal reguliert. Diese Regelung benötigt die Aktivierung eines Arousal herabsetzenden Systems, das in den neurologischen Schlafmechanismen besteht. Das Auftreten von Übersprungsverhalten wird als eine Konsequenz dieser regulatorischen Aktivierung des Schlafsystems angesehen. Die Hypothese wird dann mit den vorhandenen Übersprungsverhaltenstheorien verglichen.


The research underlying this paper has been supported by grants from the U.S. Air Force Office of Scientific Research through the European Office of Aerospace Research, the Science Research Council and the Royal Society to Professor N. Tinbergen, F. R. S. and myself. It was partly carried out at the Department of Zoology, Oxford. I am grateful to Dr. S. A. Hillyard who by revising an earlier version contributed much to whatever merits this paper has.  相似文献   
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