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251.
A video multitracking system for quantification of individual behavior in a large fish shoal: Advantages and limits 总被引:2,自引:0,他引:2
Johann Delcourt Christophe Becco Nicolas Vandewalle Pascal Poncin 《Behavior research methods》2009,41(1):228-235
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
252.
Forrest Toegel August F. Holtyn Shrinidhi Subramaniam Kenneth Silverman 《Journal of applied behavior analysis》2020,53(3):1726-1741
Polydrug use is a common problem among patients in opioid-substitution treatment. Polydrug use has been reduced by administering abstinence-reinforcement contingencies in a sequence, such that a single drug is targeted until abstinence is achieved, and then an additional drug is targeted. The present study examined effects of administering abstinence-reinforcement contingencies sequentially based on time rather than on achieved abstinence. Participants accessed paid work (about $10/hr maximum) in the Therapeutic Workplace by providing urine samples 3 times per week. The urine samples were tested for opiates and cocaine. During an induction period, participants earned maximum pay independent of drug abstinence. Then, maximum pay depended upon urine samples that were negative for opiates. Two weeks later, maximum pay depended upon urine samples that were negative for both opiates and cocaine. Opiate and cocaine abstinence increased following administration of the respective contingencies. The time-based administration of abstinence reinforcement increased opiate and cocaine abstinence. 相似文献
253.
Brandl Christopher Wille Matthias Nelles Jochen Rasche Peter Schäfer Katharina Flemisch Frank O. Frenz Martin Nitsch Verena Mertens Alexander 《Science and engineering ethics》2020,26(2):667-689
Science and Engineering Ethics - The integration of ethics into the day-to-day work of research and innovation (R&I) is an important but difficult challenge. However, with the Aachen method... 相似文献
254.
Recent research has demonstrated that both brain-injured children and children with attention deficit/hyperactivity disorder (ADHD) suffer from response inhibition deficits. To investigate whether these deficits can be influenced by motivational factors, the stop-signal task was performed with and without reward contingencies for successful inhibition. Three groups of children between 8 and 12 years of age, participated in the study: 31 children with ADHD, 37 with traumatic brain injuries (TBI), and 26 normal controls. Results indicated that, although all groups showed comparable learning effects, reward contingencies had different effects on the groups. Whereas the performance of children with ADHD under reward contingencies were brought up to the performance level of normal controls, rewards were found less effective at improving response inhibition in children with TBI. The results further support a motivational/energetic explanation of the inhibitory deficit in children with ADHD, and of a primary response inhibition deficit due to structural brain damage in children with TBI. 相似文献
255.
256.
Dynamic field theory of movement preparation 总被引:7,自引:0,他引:7
A theoretical framework for understanding movement preparation is proposed. Movement parameters are represented by activation fields, distributions of activation defined over metric spaces. The fields evolve under the influence of various sources of localized input, representing information about upcoming movements. Localized patterns of activation self-stabilize through cooperative and competitive interactions within the fields. The task environment is represented by a 2nd class of fields, which preshape the movement parameter representation. The model accounts for a sizable body of empirical findings on movement initiation (continuous and graded nature of movement preparation, dependence on the metrics of the task, stimulus uncertainty effect, stimulus-response compatibility effects, Simon effect, precuing paradigm, and others) and suggests new ways of exploring the structure of motor representations. 相似文献
257.
Emotional prosody is defined as the ability to express emotions through variations of different parameters of the human speech, such as pitch contour, intensity and duration. A recent study has discovered clear differences between men and women in the time course of emotional prosodic processing. There are several interpretations of these intriguing results that hold promise for future studies on language comprehension. 相似文献
258.
Karl Erik Schøllhammer 《Knowledge, Technology, and Policy》2008,21(3):143-148
This essay discusses the performative interventions of the contemporary Belgian artist Francis Alÿs in Mexico City and how they create a critical focus on urban reality in the Latin American mega-cities, and outline ways of intervention and interaction in the modern disassociation of the city’s economical, social, and cultural levels, taking up the challenge to suggest their unity through imagination and art. 相似文献
259.
A wide range of research suggests that the exertion of self-control is a limited resource or constrained by a motivational shift. Less attention, however, has been given to the question how self-control capacity can be restored. This study examined whether this restoration can be achieved by “presence,” the perceptual illusion of non-mediation. We suggest that the adoption of the mediated reference systems creates a “holiday from self” and restores self-control capacity. Depleted participants who saw an immersive video clip performed better in a subsequent self-control task than participants who saw a non-immersive video clip or were in a waiting group. But the concrete mechanism remains open: Self reported presence did not serve as a mediator. 相似文献
260.
Reference-related inhibition produces enhanced position discrimination and fast repulsion near axes of symmetry 总被引:3,自引:0,他引:3
Models proposed to account for reference frame effects in spatial cognition often account for performance in some tasks well, but fail to generalize to other tasks. Here, we demonstrate that a new process account of spatial working memory--the dynamic field theory (DFT)--can bridge the gap between perceptual and memory processes in position discrimination and spatial recall, highlighting that the processes underlying spatial recall also operate in position discrimination. In six experiments, we tested two novel predictions of the DFT: first, that discrimination is enhanced near symmetry axes, especially when the perceptual salience of the axis is increased; and second, that performance far from a reference axis depends on the direction in which the second stimulus is presented. The DFT also predicts the magnitude of this direction-dependent modulation. These effects arise from reference-related inhibition in the theory. We discuss how the processes captured by the DFT relate to existing psychophysical models and operate across a diverse array of spatial tasks. 相似文献