The Ponzo illusion affects grip-force but not grip-aperture scaling during prehension movements

Contextual cues such as linear perspective and relative size can exert a powerful effect on the perception of objects. This fact is demonstrated by the illusory effects that can be induced by such cues (e.g., the Ponzo railway track and Titchener circles illusions). Several recent studies have reported, however, that visual illusions based on such cues have little or no influence on the visuomotor mechanisms used to guide hand action. Furthermore, evidence of this sort has been cited in support of a distinction between visual perception and the visual control of action. In the current study, the authors investigated the effect of the Ponzo visual illusion on the control of hand action, specifically, the scaling of grip force and grip aperture during prehension movements. The results demonstrate that grip force scaling is significantly influenced by the Ponzo visual illusion, whereas the scaling of grip aperture is unaffected by the illusion.     

The Psychosocial Adjustment to Illness Scale--Self-Report: factor structure and item stability

The Psychosocial Adjustment to Illness Scale--Self-Report (PAIS-SR; Derogatis & Derogatis, 1990), a frequently used measure of adjustment in medically ill adults, was subjected to several exploratory factor analyses, with principal-axes factor extractions and varimax rotation procedures. The sample consisted of kidney, heart, liver, lung, and bone marrow transplant candidates (N = 280). The final analysis yielded a six-factor, 26-item instrument accounting for 59% of the variance. Coefficient alpha for the 26-item measure was .87, and internal consistency estimates for the factors ranged from .50 to .86. Strong correlations with other adjustment measures commonly used in the assessment of adults with chronic physical conditions support the validity of the PAIS-SR.     

Secondary prevention interventions for young drug users: a systematic review of the evidence

This paper reviews the international scientific evidence on the effectiveness of secondary prevention interventions for young drug users. The review provides insight into the effectiveness of interventions that have been evaluated using moderately strong research designs. Most of the studies included are from the United States of America. Some interventions are effective in reducing drug use and associated problems while others have no or mixed effect. Those successful in reducing drug use include behavior therapy, Minnesota 12-step programs, residential care, and general drug treatment. Those with either no effect or mixed effect include schools interventions. Involving parents and other agencies may enhance an intervention's effect. There is a lack of good quality studies outside the USA. Future interventions should focus on either low- or high-risk groups of young drug users. Future research should be conducted on a wider range of services for young people and include non-medical outcomes such as communication skills, schooling, employment, family relations, and economic costs.     

Simple arithmetic processing: the question of automaticity

In adult simple arithmetic performance, it is commonly held that retrieval of solutions occurs automatically from a network of stored facts in memory. However, such an account of performance necessarily predicts a uniform reaction time for solution retrieval and is therefore not consistent with the robust finding that reaction time increases with problem size and difficulty. Additionally, past research into arithmetic performance has relied on tasks that may have actually induced and measured attentional processing, thereby possibly confounding previous results and conclusions pertaining to automaticity. The present study therefore, attempted to more reliably assess the influence of automatic processing in arithmetic performance by utilizing a variant of the well-established semantic word-priming procedure with a target-naming task. The overall results revealed significant facilitation in naming times at SOAs of 240 and 1000 ms for congruent targets i.e., targets that represented the correct solutions to problems presented as primes (e.g., 6+8 and 14). Significant inhibition in comparison to a neutral condition (0+0 and 17) was also observed at 120 and 240 ms SOAs in naming incongruent targets (e.g., 6+8 and 17). Furthermore, response times were found to vary as a function of both arithmetic fluency and problem size. Differences in performance to addition and multiplication operations and implications for cognitive research and education are considered.     

Conjoint developmental trajectories of young adult alcohol and tobacco use

Developmental and etiological advances have set the stage for considering trajectories of problem behavior across the life course, but little work thus far addresses co-occurring problem behavior trajectories. Although recent work characterizes drinking and smoking trajectories, none has explored the course of concurrent drinking and smoking. Using panel data from the Monitoring the Future Project (N=32,087), the authors applied growth mixture modeling to 4 waves of heavy drinking and smoking in a young-adult sample. The authors extracted a single latent group membership factor from heavy drinking and smoking. Associations between trajectory classes and risk factors were relatively unique to the substance being predicted. The association of smoking with alcohol expectancies and delinquency appeared to exist by virtue of smoking's comorbidity with drinking.     

Modeling error variance in job specification ratings: the influence of rater, job, and organization-level factors

The authors modeled sources of error variance in job specification ratings collected from 3 levels of raters across 5 organizations (N=381). Variance components models were used to estimate the variance in ratings attributable to true score (variance between knowledge, skills, abilities, and other characteristics [KSAOs]) and error (KSAO-by-rater and residual variance). Subsequent models partitioned error variance into components related to the organization, position level, and demographic characteristics of the raters. Analyses revealed that the differential ordering of KSAOs by raters was not a function of these characteristics but rather was due to unexplained rating differences among the raters. The implications of these results for job specification and validity transportability are discussed.     

The evolution of domain-general mechanisms in intelligence and learning

For both humans and animals, domain-general mechanisms are fallible but powerful tools for attaining evolutionary goals (e.g., resources) in uncertain, novel environments that were not recurrent features of the environment of evolutionary adaptedness. Domain-general mechanisms interact in complex ways with domain-specific, information-encapsulated modules, most importantly by manipulating information obtained from various modules in attempting to solve novel problems. Mechanisms of general intelligence, particularly the executive functions of working memory, underlie analogical reasoning as well as the decontextualization processes that are central to human thought. Although there is a variety of evolved, special purpose learning devices, learning is also characterized by domain-general mechanisms that are able to achieve evolutionary goals by making novel and serendipitous associations with environmental cues.     

Crystallization of desire and crystallization of discontent in narratives of life-changing decisions

Two studies of adults examined personal narratives of life-changing decisions in relation to personality and well-being. Participants whose decision narratives emphasized a crystallization of desire (i.e., approaching a desired future) rather than a crystallization of discontent (i.e., escaping an undesired past; Baumeister, 1991, 1994) reported higher well-being, fewer avoidance strivings, lower Neuroticism (in Study 1 only), and better decision outcomes (in Study 2). However, neither strivings, traits, nor outcomes accounted for the relationship between crystallization of desire and well-being. The discussion considers the roles of life-changing decisions and personal narratives in research on personality, well-being, and positive personal development.     

Effects of modeling and topic stimulus on self-referent touching

Self-touching is defined as self-directed touches, e.g., scratching or rubbing, that have no apparent conscious motivation. Earlier research on self-touching focused on internal processes associated with self-touching, e.g., mental conflict, while more recent research has considered external motivators, such as an auditory or visual presentation of a provocative stimulus, e.g., leeches. Here, 110 undergraduate psychology students (68 women, 42 men; M age = 18.7 yr., SD = 1.0) were shown a video about chiggers to replicate previous findings, while simultaneously studying the social influence of self-touching modeled by the presenter. A significant interaction was found as modeled self-touching significantly increased participants' self-touching when they were also attending to the video about chiggers. The results are discussed in terms of potential processes underlying this behavior and directions for research.