Methylphenidate slows reactions of children with attention deficit disorder during and after an error

A Sternberg memory search task was administered under placebo and methylphenidate to 42 children with cross-situational attention deficit disorder (ADD), 31 children with cross-situational ADD plus oppositional features, and 25 patients with marginal ADD. Overall, stimulant medication enhanced accuracy and speed. In addition, patients reacted faster on correct responses not preceded by an error than on errors (especially false alarms) or on correct responses following an error. The slowness during error reactions may reflect decreased confidence or confusion during stimulus classification. This uncertainty may also lead subjects to respond with greater caution, hence more slowly, on correct responses following errors. Notably, methylphenidate increased the slowing of reactions on error trials as well as on correct reactions following an error. Stimulant medication may augment subjects' persistence when they are uncertain or confused, thereby heightening caution and promoting accuracy on succeeding trials. Consistent with previous reports of the generality of enhancement of performance by stimulant medication, the impact of methylphenidate was comparable for the three subtypes of ADD studied.Jaine Strauss is at Macalester College.This research was supported by National Institute of Mental Health Grants MH32103 and MH38118. We thank Rachel Avery, Christine Carriuolo, Lawrence Ota, the late Helen Pollock, and the University of Rochester's Strong Memorial Hospital Pharmacy for their assistance.     

Ist Die Limes-Theorie Der Wahrscheinlichkeit Eine Sinnvolle Idealisation?

Ohne Zusammenfassung     

Simulation of motor-neuronal networks

This research develops a theoretical connectionist-type model of the operation of the human motor system. The model includes the operation of the cerebral cortex, pons, spinal cord, and muscles. It emphasizes the parallel passage of neuronal signals, the integration of multiple signals within nuclei, and the modulation of signals as a result of sensory input. A redundant Fast Fourier Transform (FFT) procedure that analyzes EEG signals by a method similar to the one used by pontine nuclei is described.     

学校资源与早期青少年心理社会适应的关系：一项潜在转变分析

以1012名初一学生为被试进行3年的追踪研究, 采用潜在剖面分析与潜在转变分析考察了早期青少年心理社会适应的亚组分化与转变情况, 以及学校资源与性别在青少年发展适应中的作用。结果发现：(1)初一时青少年的心理社会适应分化成2个亚组：适应良好组与内化问题组, 初二与初三时青少年分化成4个适应亚组：适应良好组、内化问题组、外化问题组和同伴拒绝组; (2)从初二到初三, 适应良好组和内化问题组的青少年保持了较高的稳定性, 同伴拒绝组和外化问题组的青少年向适应良好组转变的概率最高; (3)拥有更多学校资源的青少年更可能处于或保留在适应良好组, 同时在初二时拥有更多学校资源的外化问题组和同伴拒绝组的青少年在初三时更可能向适应良好组转变; (4)初二时女生更大概率地进入内化问题组。研究结果有助于深化对早期青少年心理社会适应发展模式多样性的理解, 并提示教育人员有必要对青少年适应状况进行全面筛查和动态监测, 以便针对适应亚组和性别特点制定更为复杂的预防和干预方案。     

Within-Person Variability in Response Speed as an Indicator of Cognitive Impairment in Older Adults

ABSTRACT

Within-person variability may be an important indicator of central nervous system compromise. In this study, within-person variability in response speed was examined in community-dwelling older adults, ages 64–92 years, using a new framework that takes into account both the extent (single versus multiple domains affected) and nature (amnestic versus non-amnestic) of the cognitive impairment. Those with multiple domains of impairment were more variable than those who showed an isolated area of impairment, regardless of whether memory was one of the domains affected. Further, for those with difficulties in two or more non-memory domains, increased variability was most evident in more cognitively demanding situations, when individuals had to manipulate information held briefly in mind, switch cognitive set or inhibit an automatic response. Finally, group differentiation was better achieved when within-person variability as opposed to mean speed of performance was considered.     

Can Empathy Promote Cooperation When Status and Money Matter?

Abstract

In the present study we ask, Does empathy also support cooperative behaviors when the status (high, low) of an individual differs relative to other group members and is determined by either chance or effort? In response to this unexplored question, the present study involved a series of 4 experiments using a linear public goods game (Experiment 1–3, 4-player; Experiment 4, 2-player). Regardless of the way in which status was achieved (chance, effort), those with low status cooperated more compared with their high-status counterparts. Empathy in and of itself revealed very small overall increases in cooperative behavior. Overall, status and monetary incentives appear to be more salient than empathy in guiding behaviors in a social dilemma task.     

Primitive terms and the limits of conceptual understanding

Ignoring primitive terms leads to an infinite regress. The alternative is to account for an intuitive understanding (immediate insight) into the meaning of such terms. The current investigation proceeds on the basis of an idea of the structure of the various modes of being (modi/modalities) within which concrete (natural and social) entities function. Examples of primtive terms are given from disciplines such as mathematics, physics and logic and they are related to the general idea of a modal aspect. It is argued that primitive terms are not isolated but reveal their meaning only through their interconnections with other primitive terms that are embedded in other modal aspects. However, although primitive terms are found within the various aspects, the meaning of an aspect only comes to expression through its coherence with other aspects, evinced in modal analogies that are qualified by the core meaning of an aspect. There appears to be two options, either reduce what is irreducible or merely provide (partial) synonymous terms for given primitives. The former happens when other unique (primitive) terms are used to define a specific one and the latter when the attempted ‘definitions’ revert to terms with which the original terms could be meaningfully replaced. It is been pointed out that the coherence between primitives invites every academic discipline to account for the meaning attached to the analogies of primitive terms it is employing, without exploring this additional theme any further.