In this cross-sectional study, the mediating role of inhibition relative to speed in age-related working memory decline on different tasks was investigated. It was hypothesized that the role of inhibition is marginal or absent in a relatively "passive" or simple working memory task, but present in a relatively "active" or complex task in which the processing, rather than the storage capacity of working memory, is addressed. This hypothesis was tested with a structural equation model that was fitted on a subsample (N = 213) of the Maastricht Aging Study (MAAS). The first trial of the Verbal Learning Test (VLT) served as the passive test and the Self-Paced Auditory Serial Addition Task (SPASAT) as the active test. Results showed that the role of inhibition was absent in predicting VLT performance, whereas it was comparable to the role of speed in predicting SPASAT performance. These findings suggest a relative, task-dependent role of inhibition in explaining age-related memory decline. 相似文献
The capability of a new multitracking system to track a large number of unmarked fish (up to 100) is evaluated. This system
extrapolates a trajectory from each individual and analyzes recorded sequences that are several minutes long. This system
is very efficient in statistical individual tracking, where the individual’s identity is important for a short period of time
in comparison with the duration of the track. Individual identification is typically greater than 99%. Identification is largely
efficient (more than 99%) when the fish images do not cross the image of a neighbor fish. When the images of two fish merge
(occlusion), we consider that the spot on the screen has a double identity. Consequently, there are no identification errors during
occlusions, even though the measurement of the positions of each individual is imprecise. When the images of these two merged
fish separate (separation), individual identification errors are more frequent, but their effect is very low in statistical individual tracking. On
the other hand, in complete individual tracking, where individual fish identity is important for the entire trajectory, each identification error invalidates the results.
In such cases, the experimenter must observe whether the program assigns the correct identification, and, when an error is
made, must edit the results. This work is not too costly in time because it is limited to the separation events, accounting
for fewer than 0.1% of individual identifications. Consequently, in both statistical and rigorous individual tracking, this
system allows the experimenter to gain time by measuring the individual position automatically. It can also analyze the structural
and dynamic properties of an animal group with a very large sample, with precision and sampling that are impossible to obtain
with manual measures. 相似文献
Although complex hallucinations are extremely vivid, painful symptoms in schizophrenia, little is known about the underlying mechanisms of multisensory integration in such a phenomenon. We investigated the neural basis of these altered states of consciousness in a patient with schizophrenia, by combining state of the art neuroscientific exploratory methods like functional MRI, diffusion tensor imaging, cortical thickness analysis, electrical source reconstruction and trans-cranial magnetic stimulation. The results shed light on the functional architecture of the hallucinatory processes, in which unimodal information from different modalities is strongly functionally connected to higher-order integrative areas. 相似文献
The threat of being negatively stereotyped in math impairs performance of highly qualified females on difficult math tests, a phenomenon known as “stereotype threat”—ST. Perhaps more alarmingly, recent studies based on unselective samples of elementary-, middle-, and high-school students show that ST also operates in girls from the general population. Here we offer first evidence that ST does operate (with large effect sizes) even in middle-school girls who deny the negative gender stereotype. Children’s beliefs about the two genders math ability, therefore, do not necessarily moderate their susceptibility to ST, an important issue that remained unclear so far. This new finding is also of great practical significance: School girls’ counter-stereotypic beliefs cannot be taken as sufficient evidence for deciding whether the struggle against ST is or is not needed. Appropriate interventions should be the default option when aiming for true gender equality in math and science achievements. 相似文献
We investigated whether the moment at which an event is perceived depends on its temporal context. Participants learned a mapping between time and space by watching the hand of a clock rotating a full revolution in a fixed duration. Then the hand was removed, and a target disc was flashed within a fixed-interval duration. Participants were to indicate where the hand would have been at the time of the target. In three separate experiments, we estimated the disruption from a distractor disc that was presented before or after the target disc, with a variable time between them. The target was either revealed at the end of the trial or cued beforehand, and in the latter case, was cued by either color or temporal order. We found an attraction to the presentation time of the distractor when both events were attended equally (target revealed at the end). When the target was cued beforehand, the reported time was under- or overestimated, depending on whether the nature of distractor had to be decoded (precued by color) or not (precued by order). In summary, the perceived time of an event is always affected by other events in temporal proximity, but the nature of this effect depends on how each event is attended.
The goal of the current study is to assess the temporal dynamics of vision and action to evaluate the underlying word representations that guide infants' responses. Sixteen‐month‐old infants participated in a two‐alternative forced‐choice word–picture matching task. We conducted a moment‐by‐moment analysis of looking and reaching behaviors as they occurred in tandem to assess the speed with which a prompted word was processed (visual reaction time) as a function of the type of haptic response: Target, Distractor, or No Touch. Visual reaction times (visual RTs) were significantly slower during No Touches compared to Distractor and Target Touches, which were statistically indistinguishable. The finding that visual RTs were significantly faster during Distractor Touches compared to No Touches suggests that incorrect and absent haptic responses appear to index distinct knowledge states: incorrect responses are associated with partial knowledge whereas absent responses appear to reflect a true failure to map lexical items to their target referents. Further, we found that those children who were faster at processing words were also those children who exhibited better haptic performance. This research provides a methodological clarification on knowledge measured by the visual and haptic modalities and new evidence for a continuum of word knowledge in the second year of life. 相似文献
This paper proposes a semiparametric Bayesian framework for the analysis of associations among multivariate longitudinal categorical variables in high-dimensional data settings. This type of data is frequent, especially in the social and behavioral sciences. A semiparametric hierarchical factor analysis model is developed in which the distributions of the factors are modeled nonparametrically through a dynamic hierarchical Dirichlet process prior. A Markov chain Monte Carlo algorithm is developed for fitting the model, and the methodology is exemplified through a study of the dynamics of public attitudes toward science and technology in the United States over the period 1992?C2001. 相似文献
The human voice is the carrier of speech, but also an "auditory face" that conveys important affective and identity information. Little is known about the neural bases of our abilities to perceive such paralinguistic information in voice. Results from recent neuroimaging studies suggest that the different types of vocal information could be processed in partially dissociated functional pathways, and support a neurocognitive model of voice perception largely similar to that proposed for face perception. 相似文献