Stimulation cognitive chez les personnes âgées : effets d’une méthode de stimulation cognitive par les jeux sur les fonctions cognitives et l’estime de soi

The purpose of this study was to examine the effects of a cognitive stimulation program with games on scores to cognitive tests (processing speed, mental flexibility, working memory, inhibition) and how this program can benefit to a psycho-affective measure, self-esteem in older adults. Forty-eight participants over 60 years old took part in the experiment. They were divided into two groups: 1 group followed a program of cognitive stimulation using leisure activities with games and 1 control group in which people gathered every week. There were 8 sessions of cognitive stimulation using leisure activities like games, one-hour session a week. Measures have focused on speed of processing and executive functions (shifting, updating and inhibition). They have been evaluated before and after the training program. Results show that the cognitive stimulation program using leisure activities with games is effective on speed of processing, memory span, inhibition and self-esteem but shows no benefits on shifting and updating. These results indicate that it seems to be possible to enhance cognitive resources, inhibition and self-esteem using leisure activities with games as a tool for cognitive stimulation.     

Bilateral Transcranial Direct Stimulation Over the Primary Motor Cortex Alters Motor Modularity of Multiple Muscles

Abstract

Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has been demonstrated to modulate the motor performance of both healthy individuals and patients with neuromuscular disorders. However, the effect of tDCS on motor control of multiple muscles, which is a prerequisite to change in motor performance, is currently unknown. Using dimensionality reduction analysis, we investigated whether bilateral tDCS over M1 modulates the coordinated activity of 12 muscles. Fifteen healthy men participated in this randomized, double-blind crossover study. Each participant received a 20-min sham and 2-mA stimulation bilaterally over M1 (anode on the right M1 and cathode on the left M1), with a minimum washout period of 4?days. Muscle activation and end-point kinematics were evaluated during a task where participants reached out to a marked target with non-dominant hand as fast as possible, before and immediately after tDCS application. We found decreased similarity in motor modularity and significant changes in muscle activation in a specific motor module, particularly when reaching out to a target placed within arm’s length and improved smoothness index of movement only following 2-mA stimulation. These findings indicate that clinicians and researchers need to consider the simultaneous effect of bilateral tDCS over M1 on multiple muscles when they establish tDCS protocol to change in motor performance of patients with neuromuscular deficits.     

Evidence for a motor mechanism of pain-induced aggression instigation in humans

The automatic skeletal motor responses of 20 male and 20 female student subjects (aged 20–36) receiving a painful stimulation (electric shock) were studied by examining voluntary concomitant extensions and flexions of the arm. These movements were either of long duration, allowing for an on-line control of their execution or, of short duration, requiring extensive pre-programming. Subjects were instructed either to push or to pull a lever upon receipt of an acoustic signal, which was paired or unpaired with an electric shock. Latencies for long duration movements (regardless of direction) were reduced by reception of painful stimulation. Latencies of short duration extensions and flexions were respectively reduced and increased by painful stimulation. Latencies of short duration movements were larger for females than males, regardless of movement direction. These data suggest that painful stimulation elicits automatic movements which affect programming of the termination of simultaneous voluntary movements. Implications of these findings for the study of aggressive behavior are discussed. © 1994 Wiley-Liss, Inc.     

Canonical analysis of two convex polyhedral cones and applications

Canonical analysis of two convex polyhedral cones consists in looking for two vectors (one in each cone) whose square cosine is a maximum. This paper presents new results about the properties of the optimal solution to this problem, and also discusses in detail the convergence of an alternating least squares algorithm. The set of scalings of an ordinal variable is a convex polyhedral cone, which thus plays an important role in optimal scaling methods for the analysis of ordinal data. Monotone analysis of variance, and correspondence analysis subject to an ordinal constraint on one of the factors are both canonical analyses of a convex polyhedral cone and a subspace. Optimal multiple regression of a dependent ordinal variable on a set of independent ordinal variables is a canonical analysis of two convex polyhedral cones as long as the signs of the regression coefficients are given. We discuss these three situations and illustrate them by examples.     

时间距离、自我差异的自动激活与价值偏好

本研究对时间距离对自我差异的自动激活假说进行了检验。研究首先启动个体不同的时间自我知觉,然后利用评价性条件反射使先前激活的自我知觉中止,以检验对价值偏好的影响。结果证实了本研究的假设,当消极情绪词语和自我词语同时启动时,先前激活的自我知觉回落到未激活前的基线水平,并使得远期时间距离所引发的可能自我差异或近期时间距离所引发的当前自我差异减弱,从而导致价值偏好不再随时间线索发生系统改变。研究最后讨论了这一发现对自我调节研究的意义。     

今本《子夏易传》即唐张弧伪本考论

《经义考》和《四库》皆认为,今本《子夏易传》非但不是唐以前流传的古本《子夏易传》,也不是唐代张弧所假托伪撰的《子夏易传》,而是宋以后伪撰的另一新伪本,而唐张弧伪本已亡佚。这一观点得到了大多数学者的认可。但本文通过详细考证,认为今本《子夏易传》即宋代流传的唐张弧伪本,易学史上并不存在张弧伪本之后的新伪本《子夏易传》。考证清楚此问题,对我们更好地理解、利用今本《子夏易传》,以及对古本《子夏易传》的辑佚都有重要意义。     

The role of the human extrastriate visual cortex in mirror symmetry discrimination: a TMS-adaptation study

The human visual system is able to efficiently extract symmetry information from the visual environment. Prior neuroimaging evidence has revealed symmetry-preferring neuronal representations in the dorsolateral extrastriate visual cortex; the objective of the present study was to investigate the necessity of these representations in symmetry discrimination. This was accomplished by the use of state-dependent transcranial magnetic stimulation, which combines the fine resolution of adaptation paradigms with the assessment of causality. Subjects were presented with adapters and targets consisting of dot configurations that could be symmetric along either the vertical or horizontal axis (or they could be non-symmetric), and they were asked to perform a symmetry discrimination task on the targets while fixating the center of the screen. TMS was applied during the delay between the adapter and the test stimulus over one of four different sites: Left or Right V1/V2, or left or right dorsolateral extrastriate cortex (DLO). TMS over both Left and Right DLO reduced the adaptation effect in detecting vertical and horizontal symmetry, although the Left DLO effect on horizontal symmetry and the Right DLO effect on both vertical and horizontal symmetry were present only when considering subjects who showed a behavioral adaptation effect in the baseline No-TMS condition. Application of TMS over the Left or Right V1/V2 did not modulate the adaptation effect. Overall, these data suggest that both the Left and Right DLO contain neuronal representations tuned to mirror symmetry which play a causal role in symmetry discrimination.     

对肾移植输血问题的思考

就肾移植受者输血的几个问题进行了回顾和探讨。提出肾移植受者输血应该考虑的问题有：如何权衡输血对肾移植受者的有益作用与输血风险,输血医学的发展如何为肾移植提供更有力的保障,应该深入探讨输血有益于肾移植的机制,推进供者特异性输血在我国的应用。