Major alternatives to the Classic Experimental Design

In summary, giving up any of the three defining features of the Classic Experimental Design has (at least) two important effects. Each concession creates a significant threat to our confidence that any improvements observed were actually attributable to the treatment we are studying. At the same time, each concession opens a door by enhancing, sometimes greatly, the feasibility of conducting work in settings that are the most true to everyday clinical practice. When the work is thoughtfully and responsibly conducted, the alternative designs can contribute to clinical knowledge in a way that is equally important to the contributions made by work that conforms to the stringent requirements of the "Classic" design. In the next article, we will discuss single-time-point designs, along with the important dictum, memorized by most everyone who has taken a course called "Introduction to Research" or "Introduction to Statistics" that correlation is not causation.     

Understanding the relations among gender,disinhibition, and disruptive behavior in adolescents

This study examined whether disinhibition shows similar relations with attention-deficit/hyperactivity disorder (ADHD) and conduct disorder (CD) symptomatology among male and female adolescents. The mixed-incentive or punishment condition of Newman's go/no-go task was administered to 172 adolescents. As expected, ADHD symptoms in boys and girls were predictive of disinhibition (i.e., commission errors) in the mixed-incentive but not punishment condition. Also consistent with expectations, CD symptoms in boys were predictive of disinhibition in the mixed-incentive but not punishment condition. In contrast, CD symptoms in girls were not predictive of disinhibition in either condition. These findings are discussed in terms of implications for understanding sex differences in the etiology of ADHD and CD.     

Positive and negative symptoms of schizotypy and the Five-factor model: a domain and facet level analysis

In this study, we investigated the Five-factor model in the concurrent prediction of positive symptom schizotypy as measured by the Magical Ideation (Eckblad & Chapman, 1983) and Perceptual Aberration (Chapman, Chapman, & Raulin, 1978) scales and negative symptom schizotypy as measured by the Physical Anhedonia (Chapman, Chapman, & Raulin, 1976) and Revised Social Anhedonia (Eckblad, Chapman, Chapman, & Mishlove, 1982; Mishlove & Chapman, 1985) scales. Previous studies suggest that these measures reflect the core symptoms found in schizotypal and schizoid personality disorder (Bailey, West, Widiger, & Freiman, 1993). Negative symptoms were significantly predicted by Neuroticism (+), Extraversion (-), Openness (-), and Agreeableness (-) domains of the Revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae, 1992). Additionally, positive symptoms were significantly predicted by Neuroticism (+), Openness (+), and Agreeableness (-). In addition, we examined the validity of lower order traits in de- scribing these symptoms of character pathology. These findings lend further support for the use of domain and facet scales of the NEO-PI-R in the identification of personality pathology.     

Configural face processing develops more slowly than featural face processing

Expertise in face processing takes many years to develop. To determine the contribution of different face-processing skills to this slow development, we altered a single face so as to create sets of faces designed to measure featural, configural, and contour processing. Within each set, faces differed only in the shape of the eyes and mouth (featural set), only in the spacing of the eyes and mouth (spacing set), or only in the shape of the external contour (contour set). We presented adults, and children aged 6, 8, and 10 years, with pairs of upright and inverted faces and instructed them to indicate whether the two faces were the same or different. Adults showed a larger inversion effect for the spacing set than for the featural and external contour sets, confirming that the spacing set taps configural processing. On the spacing set, all groups of children made more errors than adults. In contrast, on the external contour and featural sets, children at all ages were almost as accurate as adults, with no significant difference beginning at age 6 on the external contour set and beginning at age 10 on the featural set. Overall, the results indicate that adult expertise in configural processing is especially slow to develop.     

Action-based and vision-based selection of input: Two sources of control

In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.     

Win-shift and win-stay learning in the short-beaked echidna (<Emphasis Type="Italic">Tachyglossus aculeatus</Emphasis>)

Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication     

Relations of Tripartite Dimensions of Emotion to Childhood Anxiety and Mood Disorders

This study examined preliminary higher-order models relating tripartite dimensions of emotion to severity of anxiety and depressive disorders in 100 clinically referred children and adolescents. In light of the accumulating support for multifactor models of vulnerability and negative emotion in children, the present investigation was designed to establish preliminary estimates of the structure and magnitude of the relations of three emotion factors with dimensions of social anxiety, depression, panic, generalized anxiety, obsessions/compulsions, and separation anxiety. Results were consistent with structures that minimally specified two higher-order emotion factors, yet only some parameter estimates were consistent with theory regarding the tripartite model. Problems with the measurement of tripartite factors and possibilities for further research are outlined.     

Seeds of discontent: Expert opinion, mass media messages, and the public image of agricultural biotechnology

Survey data are presented on opinions about agricultural biotechnology and its applications held by agricultural science faculty at highly ranked programs in the United States with and without personal involvement in biotechnology-oriented research. Respondents believed biotech holds much promise, but policy positions vary. These results underscore the relationship between opinion and stakeholder interests in this research, even among scientific experts. Media accounts are often seen as causes, rather than artifacts, of the existence of public controversy; European and now U.S. opposition to food biotechnology is often explained away in terms of such a relationship. The authors argue that where even experts are divided, public opposition cannot reasonably be attributed to poor public understanding or sensationalistic media accounts. Ethical implications for communicating science are explored.     

The Factor Structure of the Beavers Interactional Scales

Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly.