Challenge point: a framework for conceptualizing the effects of various practice conditions in motor learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

A six-factor structure of personality-descriptive adjectives: solutions from psycholexical studies in seven languages

Standard psycholexical studies of personality structure have produced a similar 6-factor solution in 7 languages (Dutch, French, German, Hungarian, Italian, Korean, Polish). The authors report the content of these personality dimensions and interpret them as follows: (a) a variant of Extraversion, defined by sociability and liveliness (though not by bravery and toughness); (b) a variant of Agreeableness, defined by gentleness, patience, and agreeableness (but also including anger and ill temper at its negative pole); (c) Conscientiousness (emphasizing organization and discipline rather than moral conscience); (d) Emotionality (containing anxiety, vulnerability, sentimentality, lack of bravery, and lack of toughness, but not anger or ill temper); (e) Honesty-Humility; (f) Intellect/Imagination/Unconventionality. A potential reorganization of the Big Five factor structure is discussed.     

Inhibition of response mode in task switching

Task inhibition was explored in two experiments that employed a paradigm in which participants switched among three tasks. Two tasks required manual choice responses based on numerical judgment (parity or magnitude), whereas a third task required an unconditional double-press of both response keys. Both experiments showed that switching to a just-abandoned task (n-2 task repetition) generally leads to a performance cost relative to switching to another task. Specifically, this task inhibition effect also occurred for the double-press task, suggesting inhibition of response mode. Prolonging the task-cuing interval showed that advance task preparation reduced only inhibition of the double-press task but not of the choice tasks (Experiment 1). Prolonging the response-cue interval led to a decrease of the inhibition effect in all tasks (Experiment 2), suggesting a time-based release of task inhibition. Together, the experiments support the notion of a response-related component of task inhibition.     

A paradoxical dissociation in the effects of midazolam on recollection and automatic processes in the process dissociation procedure

This study used midazolam-induced amnesia to explore the plausibility of the estimates provided by the process dissociation procedure (PDP), which is designed to estimate the contributions of recollection (R) and automatic (A) processes to implicit memory performance. In a double-blind, placebo-controlled, within-subject design with 24 participants, single midazolam doses were administered intravenously, and word stem completion performance was used to calculate PDP estimates. A dissociation was observed such that midazolam decreased R but increased A estimates relative to placebo. Given that a manipulation that induces amnesia would not be expected to facilitate a memory process, these results add to the accumulating body of evidence suggesting that PDP estimates are not always theoretically plausible. Such evidence raises important questions about the use of the PDP.     

Personality and the goal-striving process: the influence of achievement goal patterns,goal level,and mental focus on performance and enjoyment

The purpose of this study is to examine the mechanisms by which personality traits influence performance and satisfaction. Specifically, the authors examined how 3 personality characteristics derived from self-determination theory (autonomy, control, and amotivated orientations) influence performance and enjoyment through achievement goal patterns, goal level, and mental focus. Data were collected from 284 students at 5 points in time. In particular, mental focus emerged as an important aspect of the self-regulation process. The results suggest that global personality traits can help researchers to understand and predict the motivational strategies that people use while working toward goals in achievement settings.     

How are social identities linked to self-conception and intergroup orientation? The moderating effect of implicit theories

Social identity approaches assume that social identification affects both self-conception and intergroup orientation. The authors contend that such social identification effects are accentuated when people hold a fixed view of human character and attribute immutable dispositions to social groups. To these individuals, social identities are immutable, concrete entities capable of guiding self-conception and intergroup orientation. Social identification effects are attenuated when people hold a malleable view of human character and thus do not view social identities as fixed, concrete entities. The authors tested and found support for this contention in three studies that were conducted in the context of the Hong Kong 1997 political transition, and discussed the findings in terms of their implications for self-conceptions and the meaning of social identification.     

Development and validation of an altruism scale for adults

A new self-report scale, the Altruism Scale for Adults, of 28 items was developed. 14 items were from the Altruism subscale of Wrightsman's Philosophies of Human Nature Scale, and the other 14 items were newly constructed. The scale, anchored by 1: true or 2: false, was administered to 592 Korean men and women in eight subgroups. Cronbach alpha internal consistency was .89, and test-retest reliabilities (n = 52) over 1 and 5 wk. were .90 and .80, respectively. Campbell and Fiske's 1959 multitrait-multimethod analysis showed satisfactory convergent and discriminant validities. Overall results were promising for use of the scale in research and for practical purposes.     

Cognitive Testing Battery: differences among groups with dementia, Huntington's disease, and controls

This study evaluated a new test for dementia, the Cognitive Testing Battery, used for over six years in outpatient clinics for aging-related disorders. This battery was developed to be brief, easy to administer, and to provide useful feedback as a cognitive profile for clinicians, patients, and caregivers. 489 participants were tested during a 5-yr. period. Multidisicplinary teams diagnosed these patients with dementia, depression, or Huntington's Disease. A control group was also included. Groups were then compared on the 10 key subscales that subserve dementia populations. Analysis showed there were significant differences among the groups on all measures and that selected scales differentiated the groups. The total score maximally differentiated the groups, and the dementia group was most different from the other groups.     

The perception of minimal structures: performance on open and closed versions of visually presented Euclidean travelling salesperson problems

The planar Euclidean version of the travelling salesperson problem (TSP) requires finding a tour of minimal length through a two-dimensional set of nodes. Despite the computational intractability of the TSP, people can produce rapid, near-optimal solutions to visually presented versions of such problems. To explain this, MacGregor et al (1999, Perception 28 1417-1428) have suggested that people use a global-to-local process, based on a perceptual tendency to organise stimuli into convex figures. We review the evidence for this idea and propose an alternative, local-to-global hypothesis, based on the detection of least distances between the nodes in an array. We present the results of an experiment in which we examined the relationships between three objective measures and performance measures of optimality and response uncertainty in tasks requiring participants to construct a closed tour or an open path. The data are not well accounted for by a process based on the convex hull. In contrast, results are generally consistent with a locally focused process based initially on the detection of nearest-neighbour clusters. Individual differences are interpreted in terms of a hierarchical process of constructing solutions, and the findings are related to a more general analysis of the role of nearest neighbours in the perception of structure and motion.