Effects of Socioeconomic Status (SES) Information on Cognitive Ability Inferences: When Low-SES Students Make Use of a Self-Threatening Stereotype

Two studies tested whether students' socioeconomic status (SES) and academic achievement level moderate their use of the SES stereotype (i.e., the belief that the low-SES individuals are intellectually inferior to their high-SES counterparts). In Study 1, low versus high achievers with a low versus a high SES were given social class information (derived from a pilot study) about several targets and were then asked to infer these targets' memory ability. In Study 2, participants were given memory performance information about several targets and were then asked to infer these targets' possessions and cultural activities (i.e., SES indicators). In both studies, only the low-SES students generated stereotype-consistent inferences.     

Does the radial arm maze necessarily test spatial memory?

Since its design 25 years ago (Olton & Samuelson, 1976), the eight-arm radial maze has become very popular and is now widely used to assess spatial memory in rodents. Two versions of the full-baited maze protocol are present in the literature: with or without confinement between the visit of each arm. The confinement was introduced by Olton himself as early as 1977 (Olton, Collison, & Werz, 1977) to eliminate stereotypic behaviors that he had previously observed. It is widely regarded that the confinement prevents rodents from developing these response patterns, and as such it is considered an improved procedure to test spatial memory. Surprisingly, to the best of our knowledge, no study has been especially designed to demonstrate the efficacy of the confinement in blocking the stereotypic behaviors of the animals. The present study compares the strategies of rats trained with or without a confinement procedure. The results show that, after nine days of training, rats submitted to a 5- or a 10-s confinement reach the same level of performance as rats without confinement. The confinement totally prevents stereotypic behaviors like clockwise serial searching strategies which are often observed without confinement. Even a 0-s confinement is sufficient to prevent clockwise strategies, but rats seem to develop other stratagems which do not imply spatial memory. Furthermore, rats previously trained without confinement are unable to perform the task when confinement is introduced on a test day. In contrast, rats previously trained with confinement perform the task correctly when the confinement is no longer present. Thus, without confinement, good levels of performance can be achieved without precise spatial representations.     

Neural representations during sleep: from sensory processing to memory traces

In the course of a day, the brain undergoes large-scale changes in functional modes, from attentive wakefulness to the deepest stage of sleep. The present paper evaluates how these state changes affect the neural bases of sensory and cognitive representations. Are organized neural representations still maintained during sleep? In other words, despite the absence of conscious awareness, do neuronal signals emitted during sleep contain information and have a functional relevance? Through a critical evaluation of the animal and human literature, neural representations at different levels of integration (from the most elementary sensory level to the most cognitive one) are reviewed. Recordings of neuronal activity in animals at presentation of neutral or significant stimuli show that some analysis of the external word remains possible during sleep, allowing recognition of behaviorally relevant stimuli. Event-related brain potentials in humans confirm the preservation of some sensory integration and discriminative capacity. Behavioral and neuroimaging studies in humans substantiate the notion that memory representations are reactivated and are reorganized during post-learning sleep; these reorganisations may account for the beneficial effects of sleep on behavioral performance. Electrophysiological results showing replay of neuronal sequences in animals are presented, and their relevance as neuronal correlates of memory reactivation is discussed. The reviewed literature provides converging evidence that structured neural representations can be activated during sleep. Which reorganizations unique to sleep benefit memory representations, and to what extent the operations still efficient in processing environmental information during sleep are similar to those underlying the non-conscious, automatic processing continually at work in wakefulness, are challenging questions open to investigation.     

Investigating the Granularity of the Undo Function in Human-Computer Interfaces

Cet article présente trois expériences sur la granularité de la fonction défaire dans les interfaces humain-ordinateur. Les deux premières identifient et analysent les attentes des utilisateurs à propos de la granularité de la fonction défaire dans une tâche de traitement de texte et dans une tâche de dessin. La troisième est plus spécifique et porte sur les attentes des utilisateurs quant à la façon de défaire différentes catégories d'actions dans une tâche de dessin. Les résultats montrent qu'il existe des différences individuelles majeures dans les stratégies utilsées pour défaire, que I'on doit tenir compte des catégories d'actions dans la définition de la granularité de défaire et que les utilisateurs s'attendent à ce que presque toutes les sortes d'actions soient défaisables.
This paper presents three experiments on the granularity of the undo function in user-computer interfaces. The first two identify and analyse user expectations about the grain of undo in a word processing task and in a graphics task. The third one is more specific and tests how users expect different categories of actions to be undone in a graphics task. The results show that there are major individual differences in undo strategies, that action categories must be taken into account when defining undo granularity, and that users expect almost all kinds of actions to be undoable.     

Repeated Effects of Vigorous Interval Training in Basketball,Running-Biking,and Boxing on the Physical Self-Perceptions of Obese Adolescents

This study aims to examine the repeated effects of three sessions of vigorous interval training (VIT) in basketball, running-biking, and boxing on the physical self-perceptions (PSP) of obese adolescents participating in a dietary program. A sample of 24 obese adolescents performed the consecutive VIT sessions every week for 5 weeks. PSP were measured immediately after each training session. Analyses of covariance were used to examine changes in PSP. The results showed rapid and constant increases in PSP with significant differences according to sex, time, type of VIT, and an interaction of sex by time by type of VIT, mainly for basketball.     

Remaking memories: reconsolidation updates positively motivated spatial memory in rats

There is strong evidence that reactivation of a memory returns it to a labile state, initiating a restabilization process termed reconsolidation, which allows for updating of the memory. In this study we investigated reactivation-dependent updating using a new positively motivated spatial task in rodents that was designed specifically to model a human list-learning paradigm. On Day 1, rats were trained to run to three feeders (List 1) for rewards. On Day 2, rats were trained to run to three different feeders (List 2) in either the same (Reminder condition) or a different (No Reminder condition) experimental context than on Day 1. On Day 3, rats were cued to recall List 1. Rats in the Reminder condition made significantly more visits to List 2 feeders (intrusions) during List 1 recall than rats in the No Reminder condition, indicating that the reminder triggered reactivation and allowed integration of List 2 items into List 1. This reminder effect was selective for the reactivated List 1 memory, as no intrusions occurred when List 2 was recalled on Day 3. No intrusions occurred when retrieval took place in a different context from the one used at encoding, indicating that the expression of the updated memory is dependent upon the retrieval context. Finally, the level of intrusions was highest when retrieval took place immediately after List 2 learning, and generally declined when retrieval occurred 1-4 h later, indicating that the List 2 memory competed with short-term retrieval of List 1. These results demonstrate the dynamic nature of memory over time and the impact of environmental context at different stages of memory processing.     

The expression of uncertainty: Two contextual effects

Abstract

Since Foley (1959), the technique of evaluating common expressions of uncertainty on a numerical scale has often been used in an attempt to define such expressions more accurately. Two contextual factors - (1) the composition of the set of expressions and (2) the definition of the scale - were studied in the present experiment to determine their effect on bow such expressions are encoded. Psychophysical theories on series effects and, in particular, the range-frequency model (Parducci, 1983), predict that the composition of a set is one of the determining factors of contrast effects. The scale definition factor determines the lower limit of the rating scale, which represents either uncertainty or negative certainty. The effect of this factor is assumed to depend upon the reference universe outlined in the problem statement and, in particular, upon whether that universe is strictly limited or not. An experiment was conducted to contrast two sets of expressions, two scale definitions and two ways of presenting the problem (the doubt was applied either to a choice of two events or to the occurrence of an event in an unspecified universe). The results provide evidence of a set composition effect and an interaction between the scale definition and the presentation of the problem. This is consistent with the proposed model, which accounts for the specific effects of the judgement task while eliminating the need to consider the variability of the meanings themselves. Proposals for developing this line of research are presented in the discussion.