Dissociative patterns of foreperiod effects in temporal discrimination and reaction time tasks

This study examined whether the process of temporal preparation for a target stimulus is the same regardless of the task required by the target stimulus. To this end, the same variable-foreperiod design was used in a temporal discrimination task (Experiment 1) and a reaction time task (Experiment 2). In Experiment 1, both temporal sensitivity and perceived duration increased as a function of foreperiod, whereas in Experiment 2, foreperiod did not influence reaction time. Furthermore, both temporal sensitivity and perceived duration revealed an asymmetric sequential effect of foreperiod, but the pattern of this effect was opposite to the pattern observed in the reaction time task. Together these dissociative patterns of foreperiod effects suggest that the mechanism of temporal preparation depends on the task required by the target stimulus.     

Timing inter-reward intervals

Rats judged inter-reward intervals (IRIs) in a two-alternative, forced-choice task. The IRI was either short (S) or long (L). At the end of each IRI, two response levers were inserted into the box. A press to the lever designated as correct or incorrect produced a large (3-5 food pellets) or small (1 pellet) reward, respectively. Psychophysical functions were obtained by testing intermediate IRIs, which were followed by the small reward, independent of the response location. S and L intervals were manipulated across groups, as specified (in seconds) by the group name, S-L: 3-12 (n=12), 25-100 (n=12), and 50-200 (n=7). The psychophysical functions (p[L] vs. IRI) were ogival in shape and had bisection points (p[S]=p[L]=0.5) near the geometric mean of S and L intervals. The psychophysical functions did not superimpose in relative time (IRI/L). Instead, 3-12 was timed with greater relative sensitivity than were 25-100 and 50-200.     

运动视觉中计时行为的控制操作理论

运动视觉中的计时行为分为两类 :拦截行为和制动行为。“环境—活动者系统”(EAS)中的信息决定着计量行为的控制操作。本文阐明了信息和EAS的特性 ,通过对 tau-margin在拦截行为中的作用以及视觉变量τ对于制动操作重要性的分析 ,论述了运动视觉中计时行为的控制操作理论。     

Matching of numerical symbols with number of responses by pigeons

Pigeons were trained to peck a certain number of times on a key that displayed one of several possible numerical symbols. The particular symbol displayed indicated the number of times that the key had to be pecked. The pigeons signalled the completion of the requirement by operating a separate key. They received a food reward for correct response sequences and time-out penalties for incorrect response sequences. In the first experiment nine pigeons learned to allocate 1, 2, 3 or 4 pecks to the corresponding numerosity symbols s ₁, s ₂, s ₃ and s ₄ with levels of accuracy well above chance. The second experiment explored the maximum set of numerosities that the pigeons were capable of handling concurrently. Six of the pigeons coped with an s ₁–s ₅ task and four pigeons even managed an s ₁–s ₆ task with performances that were significantly above chance. Analysis of response times suggested that the pigeons were mainly relying on a number-based rather than on a time-based strategy. Received: 11 October 1999 / Accepted after revision: 27 January 2000     

Movement Speed and Accuracy in Space and Time: The Complementarity of Error Distributions

Movement speed-accuracy trade-off is a function of the space-time constraints of the task. We investigated the space-time account of Hancock and Newell (1985) and the hypothesis of complementarity between the four moments of the error distribution in space and time. Twelve participants performed 15 conditions in a line drawing task composed of different spatial (10, 20, and 30 cm) and temporal (250 to 2,500 ms) criteria. The results showed that all moments of distributions changed systematically between conditions but there were some departures from the Hancock and Newell predictions. In contrast, individual analysis revealed the complementarity of the spatial and temporal error including a trade-off between the four moments of error. These findings support a complementary space-time account of movement speed and accuracy.     

Fractal properties and short-term correlations in motor control in cycling: influence of a cognitive challenge

Fluctuations in cyclic tasks periods is a known characteristic of human motor control. Specifically, long-range fractal fluctuations have been evidenced in the temporal structure of these variations in human locomotion and thought to be the outcome of a multicomponent physiologic system in which control is distributed across intricate cortical, spinal and neuromuscular regulation loops.Combined with long-range correlation analyses, short-range autocorrelations have proven their use to describe control distribution across central and motor components.We used relevant tools to characterize long- and short-range correlations in revolution time series during cycling on an ergometer in 19 healthy young adults. We evaluated the impact of introducing a cognitive task (PASAT) to assess the role of central structures in control organization.Autocorrelation function and detrending fluctuation analysis (DFA) demonstrated the presence of fractal scaling. PSD in the short range revealed a singular behavior which cannot be explained by the usual models of even-based and emergent timing.The main outcomes are that (1) timing in cycling is a fractal process, (2) this long-range fractal behavior increases in persistence with dual-task condition, which has not been previously observed, (3) short-range behavior is highly persistent and unaffected by dual-task.Relying on the inertia of the oscillator may be a way to distribute more control to the periphery, thereby allocating less resources to central process and better managing additional cognitive demands. This original behavior in cycling may explain the high short-range persistence unaffected by dual-task, and the increase in long-range persistence with dual-task.     

Perceived control effects on religiosity and quality of life among young adults

The study investigated the mediating role of perceived control in the association between religiosity and quality of life among young adults in south-west Nigeria. Data were collected from a sample of 1 050 young adults (mean age = 29.8, SD = 4.61; female = 38.7%). Regression analysis was utilised to predict quality of life from religiosity, partialling out perceived control. Findings suggest internal religiosity to predict an environmental domain of quality of life through perceived control. Perceived constraints appear to explain the association between internal religiosity and the environmental domain of quality of life.     

Uncertainty,Indeterminacy, and Agent-Centred Constraints

Common-sense morality includes various agent-centred constraints, including ones against killing unnecessarily and breaking a promise. However, it's not always clear whether, had an agent ?-ed, she would have violated a constraint. And sometimes the reason for this is not that we lack knowledge of the relevant facts, but that there is no fact about whether her ?-ing would have constituted a constraint-violation. What, then, is a constraint-accepting theory (that is, a theory that includes such constraints) to say about whether it would have been permissible for her to have ?-ed? In this paper, I canvass various possible approaches to answering this question and I argue that teleology offers the most plausible approach—teleology being the view that every act has its deontic status in virtue of how its outcome (or prospect) ranks, relative to those of its alternatives. So although, until recently, it had been thought that only deontological theories can accommodate constraints, it turns out that teleological theories not only can accommodate constraints, but can do so more plausibly than deontological theories can.     

Integrative problem-centered metaframeworks therapy I: core concepts and hypothesizing

Over the last 20 years psychotherapy and family therapy have been inundated with a plethora of empirically validated treatments for particular disorders. That trend will increase. Psychotherapists will increasingly be exhorted and ultimately required to integrate empirical data and multicultural competence into their practice. Additionally, individual psychotherapy's default dominance of psychotherapeutic discourse needs to integrate and come to theoretical and clinical terms with the implications of the growing body of research demonstrating the validity and value of a multisystemic perspective. This article (and its companion article) presents a comprehensive, integrative, multisystemic, and empirically informed psychotherapeutic perspective to help therapists and psychotherapy trainers successfully address these challenges-Integrative Problem Centered Metaframeworks (IPCM) Therapy. This first article presents and illustrates IPCM's theoretical foundation, core concepts, and "case formulating" components. It delineates a Blueprint for the practice and teaching of 21st century psychotherapists who can meld science and art into best practice.     

青春期开始时间早晚对初中女生自我概念的影响

目的:探讨青春期开始时间早晚对初中女生自我概念发展的影响。方法:整群抽取初一至初三年龄12-14岁的女生共658人,采用青春期发育量表、田纳西自我概念量表进行测量。结果:①绝大多数12至14岁的女生青春期发育状态处于青春期中和青春期晚期（二者合占90%）;②年龄×青春期发育水平的方差分析显示,在自我概念各因子分及总分上,年龄和青春期发育水平的主效应均不显著;③在家庭自我、社会自我、自我认同、自我行动以及自我概念总分上年龄与青春期发育水平交互效应显著,高年龄低青春期发展水平和低年龄高青春期发展水平的初中女生的得分均较低。结论:青春期开始时间早晚可能对初中女生的自我概念的发展有一定影响,青春期开始时间晚或早均不利于女生自我概念的发展。