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261.
This study describes infants’ behaviors with objects in relation to age, body position, and object properties. Object behaviors were assessed longitudinally in 22 healthy infants supine, prone, and sitting from birth through 2 years. Results reveal: (1) infants learn to become intense and sophisticated explorers within the first 6 months of life; (2) young infants dynamically and rapidly shift among a variety of behavioral combinations to gather information; (3) behaviors on objects develop along different trajectories so that behavioral profiles vary across time; (4) object behaviors are generally similar in supine and sitting but diminished in prone; and (5) infants begin matching certain behaviors to object properties as newborns. These data demonstrate how infants learn to match their emerging behaviors with changing positional constraints and object affordances.  相似文献   
262.
Multi-store models of working memory (WM) have given way to more dynamic approaches that conceive WM as an activated subset of long-term memory (LTM). The resulting framework considers that memory representations are governed by a hierarchy of accessibility. The activated part of LTM holds representations in a heightened state of activation, some of which can reach a state of immediate accessibility according to task demands. Recent neuroimaging studies have studied the neural basis of retrieval information with different states of accessibility. It was found that the medial temporal lobe (MTL) was involved in retrieving information within immediate access store and outside this privileged zone. In the current study we further explored the contribution of MTL to WM retrieval by analyzing the consequences of MTL damage to this process considering the state of accessibility of memory representations. The performance of a group of epilepsy patients with left hippocampal sclerosis in a 12-item recognition task was compared with that of a healthy control group. We adopted an embedded model of WM that distinguishes three components: the activated LTM, the region of direct access, and a single-item focus of attention. Groups did not differ when retrieving information from single-item focus, but patients were less accurate retrieving information outside focal attention, either items from LTM or items expected to be in the WM range. Analyses focused on items held in the direct access buffer showed that consequences of MTL damage were modulated by the level of accessibility of memory representations, producing a reduced capacity.  相似文献   
263.
To date, cognitive intervention research has provided mixed but nevertheless promising evidence with respect to the effects of cognitive training on untrained tasks (transfer). However, the mechanisms behind learning, training effects and their predictors are not fully understood. Moreover, individual differences, which may constitute an important factor impacting training outcome, are usually neglected. We suggest investigating individual training performance across training sessions in order to gain finer-grained knowledge of training gains, on the one hand, and assessing the potential impact of predictors such as age and fluid intelligence on learning rate, on the other hand. To this aim, we propose to model individual learning curves to examine the intra-individual change in training as well as inter-individual differences in intra-individual change. We recommend introducing a latent growth curve model (LGCM) analysis, a method frequently applied to learning data but rarely used in cognitive training research. Such advanced analyses of the training phase allow identifying factors to be respected when designing effective tailor-made training interventions. To illustrate the proposed approach, a LGCM analysis using data of a 10-day working memory training study in younger and older adults is reported.  相似文献   
264.
A lack of perceived control over anxiety-related situations is theorized to be characteristic of anxiety disorders in children and adolescents. In the current study we tested several theoretical predictions and developmental variation with the Dutch translation of the Anxiety Control Questionnaire for Children (ACQ-C). The theoretical factor structure of anxiety control was tested using Confirmatory Factor Analysis (CFA) in 548 non-referred children (8–18 years old, M?=?12.5 years; 50.7 % girls). The incremental predictive validity of perceived control for anxiety status was assessed using logistic regression in 141 clinically anxious children (age M?=?12.6 years; 56.7 % girls) and 298 non-referred non-anxious children (age M?=?12.6 years; 52.7 % girls). CFA showed that both a one-factor model and two-factor model (perceived control over internal reactions and external events) fit well. The one-factor model proved invariant across age and gender. Internal consistency was excellent (Cronbach’s α?=?.93). Two-month test-retest reliability was adequate. The ACQ-C was able to incrementally predict diagnostic status, even after controlling for age, gender and self-reported anxiety symptoms. Finally, both younger children and girls reported less perceived control, independent of anxiety level. Findings advance the understanding of the psychometric properties of the ACQ-C, the role of control in childhood anxiety and point to the potential utility of the ACQ-C in both clinical and community samples. The Dutch translation of the ACQ-C demonstrated sound psychometric properties.  相似文献   
265.
It has long been known that eye movements are functionally involved in the generation and maintenance of mental images. Indeed, a number of studies demonstrated that voluntary eye movements interfere with mental imagery tasks (e.g., Laeng and Teodorescu in Cogn Sci 26:207–231, 2002). However, mental imagery is conceived as a multifarious cognitive function with at least two components, a spatial component and a visual component. The present study investigated the question of whether eye movements disrupt mental imagery in general or only its spatial component. We present data on healthy young adults, who performed visual and spatial imagery tasks concurrently with a smooth pursuit. In line with previous literature, results revealed that eye movements had a strong disruptive effect on spatial imagery. Moreover, we crucially demonstrated that eye movements had no disruptive effect when participants visualized the depictive aspects of an object. Therefore, we suggest that eye movements serve to a greater extent the spatial than the visual component of mental imagery.  相似文献   
266.
Free association is a task that requires a subject to express the first word to come to their mind when presented with a certain cue. It is a task which can be used to expose the basic mechanisms by which humans connect memories. In this work, we have made use of a publicly available database of free associations to model the exploration of the averaged network of associations using a statistical and the adaptive control of thought–rational (ACT-R) model. We performed, in addition, an online experiment asking participants to navigate the averaged network using their individual preferences for word associations. We have investigated the statistics of word repetitions in this guided association task. We find that the considered models mimic some of the statistical properties, viz the probability of word repetitions, the distance between repetitions and the distribution of association chain lengths, of the experiment, with the ACT-R model showing a particularly good fit to the experimental data for the more intricate properties as, for instance, the ratio of repetitions per length of association chains.  相似文献   
267.
268.
The ability to recognize and label emotional facial expressions is an important aspect of social cognition. However, existing paradigms to examine this ability present only static facial expressions, suffer from ceiling effects or have limited or no norms. A computerized test, the Emotion Recognition Task (ERT), was developed to overcome these difficulties. In this study, we examined the effects of age, sex, and intellectual ability on emotion perception using the ERT. In this test, emotional facial expressions are presented as morphs gradually expressing one of the six basic emotions from neutral to four levels of intensity (40%, 60%, 80%, and 100%). The task was administered in 373 healthy participants aged 8–75. In children aged 8–17, only small developmental effects were found for the emotions anger and happiness, in contrast to adults who showed age‐related decline on anger, fear, happiness, and sadness. Sex differences were present predominantly in the adult participants. IQ only minimally affected the perception of disgust in the children, while years of education were correlated with all emotions but surprise and disgust in the adult participants. A regression‐based approach was adopted to present age‐ and education‐ or IQ‐adjusted normative data for use in clinical practice. Previous studies using the ERT have demonstrated selective impairments on specific emotions in a variety of psychiatric, neurologic, or neurodegenerative patient groups, making the ERT a valuable addition to existing paradigms for the assessment of emotion perception.  相似文献   
269.
This study analyzes the differences in job satisfaction of older European people (aged 50-64), with or without disabilities, who are employed in either the public or the private sector. Using the data taken from the Survey of Health, Ageing and Retirement in Europe (SHARE) for the years 2004, 2007 and 2011, job satisfaction equations are estimated for workers from both the public and private sectors, with panel data techniques that include variables related to the worker's degree of disability (nondisabled, non-limited disabled, and limited disabled), among others. The results show that the disabled workers who are limited in their everyday activities are less satisfied in both the public and private sectors than those who are non-disabled and non-limited. In addition, the levels of job satisfaction for non-limited disabled people are higher than their non-disabled counterparts but only in the public sector. From a point of view of public policies, it is necessary to design and undertake measures and actions that would contribute to improving the levels of job satisfaction of older workers with disabilities, especially among those who are limited in their everyday activities.  相似文献   
270.
In my book, Cities and Immigration, I suggest shifting responsibilities for the integration of immigrants from the state to the city level. The articles in this issue challenge some of my suggestions. I discuss these challenges with regard to three questions: should a city enjoy greater autonomy to decide who, and how many, immigrants should settle within its borders? Should immigrants enjoy local voting rights even before naturalization? And is there a morally preferable model for integrating immigrants into the city?  相似文献   
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