Stimulus control and delayed reinforcement

Pigeons were tested for generalization along the line-orientation dimension, after being trained on various two-component multiple schedules. The first component contained either a variable-interval 1-min schedule of immediate reinforcement or an extinction schedule and was associated with a plain white key (S1). The second component contained a variable-interval 1-min schedule of delayed reinforcement and was associated with a black line on a white background (S2). The major results showed that (a) decremental gradients were obtained around the stimulus associated with the delayed reinforcement component when S1 was associated with extinction, but that incremental gradients were obtained when S1 was associated with immediate reinforcement, (b) the subjects' pretraining did not affect the generalization gradients if sufficient training on the terminal multiple schedule was provided, and (c) changing the S1 schedule from immediate reinforcement to extinction produced behavioral contrast if reinforcement was delayed for 10 sec during S2, but not if it was delayed for 20 sec.     

Control theories in motor behavior

The goal of contemporary motor control theorist is the delineation of the “language” of movements. That is, in what unambiguous code are the parameters of movement specified, given the composition of the human body? In this pursuit not only are the elements of the language of movement sought, but the rules of combination or syntax of movement are also to be derived. This paper compares a number of motor control theories according to the form of control they exhibit and according to their ability to address issues in the area. Recurring theoretical trends in motor control are examined and the evidence for each is reviewed, emphasizing their explanatory power in the classical problems of control: motor equivalence (Hebb 1949), complexity (Bernstein 1967), and variability (Glencross 1980; Schmidt 1975, 1976).     

Reliability of upper extremity kinematics while performing different tasks in individuals with stroke

Assessments of upper extremity performance typically include qualitative rather than quantitative measures of functional ability. Kinematic analysis is an objective, discriminative measure that quantifies movement biomechanics; however, the use within the poststroke impaired upper extremity is not well established. The purpose of this study was to examine the reliability of upper extremity kinematics in 18 individuals with stroke and 9 healthy controls. Participants performed reaching and grasping tasks over 2 separate days and metrics included movement time, peak velocity, index of curvature, trunk displacement, maximum aperture, and percentage of the movement cycle where maximum aperture occurred. The results showed moderate to high intraclass correlation and low standard error of measurement values for most variables, demonstrating that kinematic analysis may be a feasible and useful tool to quantify upper extremity movement after stroke.     

A comparative analysis of North American adolescent and adult mass murderers

Thirty adult mass murderers and 34 adolescent mass murderers in North America are compared on both offender and offense variables to delineate similarities and differences. Findings indicate a plethora of psychiatric disturbances and odd/reclusive and acting-out personality traits. Predisposing factors include a fascination with weapons and war among many of the adolescents and the development of a "warrior mentality" in most of the adults. Precipitating factors indicate a major rejection or loss in the hours or days preceding the mass murder. Results are interpreted through the lens of threat assessment for targeted violence (Borum, Fein, Vossekuil, & Bergland 1999), recognizing that a fact-based, dynamic behavioral approach is most useful for mitigating risk of such an extremely low-base-rate violent crime.     

WOMEN AND THE AMERICAN PSYCHOLOGICAL ASSOCIATION

Women have been active in the American Psychological Association (APA) almost from the beginning. In general, however, they did not attain high-level office, editorships, and significant committee posts at the same level as their male counterparts. During one 51-year period, for example, no women were elected to the APA presidency. Despite protests, little changed. Finally, in the 1970s, the climate in the APA shifted. The Committee on Women in Psychology was formed, as was the APA Division of the Psychology of Women. From then on, women's issues have remained an important concern of the association.     

Treatment Foster Care in a System of Care: Sequences and Correlates of Residential Placements

We examined Treatment Foster Care (TFC) in residential trajectories for youth with psychiatric disorders and aggressive behavior. We analyzed residential placements of a statewide sample of youth during the 12 months preceding and following admission to TFC. Prior to TFC, the majority of youth were residing in more restrictive settings (group homes or residential treatment). Two-thirds of youth remained in TFC throughout the follow-up year. Of those who left, nearly half returned home, and slightly fewer were discharged to group homes. By the end of the 12-month follow-up period, rates of group home use were similar to those seen in the pre-TFC period. Movement out of TFC during the year was associated with being older at placement and with increased problem behavior (particularly externalizing behaviors). TFC serves as a step-down placement for a substantial number of youth. However, this is not the only way it is used, and models based on short-term transitioning or reunification with families may not be widely implemented or relevant in practice. Additional research is needed to understand current functions of TFC in residential trajectories and to maximize its utility in systems of care.     

Auditory temporal processing deficits in children with periventricular brain injury

The present study investigated whether auditory temporal processing deficits are related to the presence and/or the severity of periventricular brain injury and the reading difficulties experienced by extremely low birthweight (ELBW: birthweight <1000 g) children. Results indicate that ELBW children with mild or severe brain lesions obtained significantly lower scores on a test requiring auditory temporal order judgments than ELBW children without periventricular brain injury or children who were full-term. Structural equation modeling indicated that a model in which auditory temporal processing deficits predicted speech sound discrimination and phonological processing ability provided a better fit for the data than did a second model, which hypothesized that auditory temporal processing deficits are associated with poor reading abilities through a working memory deficit. These findings suggest that an impairment in auditory temporal processing may contribute to the reading difficulties experienced by ELBW children.     

Specific language impairment in children: A cross-linguistic study

A common profile in English-speaking specifically language-impaired children is a moderate deficit across a broad range of linguistic features and a more marked, selective impairment in using bound morphemes and components of the verb system. To gain a clearer understanding of the nature of these more serious problems, we examined the speech of monolingual Italian-speaking as well as English-speaking children with specific language impairment. The evidence suggested that phonological factors contributed significantly to these children's extraordinary problems with particular linguistic features. Contrary to expectations, other marked deficits seemed more related to the opacity of the rules involved and homonymity with other morphemes than to problems with formal grammatical devices in general or components of the verb system in particular.     

Theory of Mind in Infants and Young Children: A Review

Theory of mind, or mindreading, refers to our uniquely human capacity to infer what is in other people's minds. Recent research suggests that “implicit” elements of this ability can be seen as early as the second year of life, in infants’ spontaneous helping, communicative, and eye‐gaze behaviours. More “explicit” verbally mediated mindreading skills emerge in the preschool period, and these are positively linked to social competence. Research with typically developing children as well as those with autism spectrum disorders suggests that exposure to conversation about mental states promotes theory of mind development.