Effects of component length and of the transitions among components in multiple schedules

Pigeons received equal variable-interval reinforcement during presentations of two line-orientation stimuli while five other orientations appeared in extinction. Component duration was 30 seconds for all orientations and the sequence was arranged so that each orientation preceded itself and each other orientation equally often. The duration of one component (0°) was shortened to 10 seconds and the other (90°) was lengthened to 50 seconds. All animals showed large increases in response rate in the shortened component and this increase was recoverable after an interpolated condition in which all components were again 30 seconds in duration. This effect was replicated in a second experiment in which component duration was changed from 150 seconds to 50 seconds and 250 seconds. An examination of local contrast effects during the first experiment showed that the shortened component produced local contrast during subsequent presentations of the lengthened component, just as would a component associated with more frequent reinforcement. When the presentation sequence was changed so that the lengthened component was always followed by the shortened component, response rates generally increased during the lengthened component. When the sequence was arranged so that the shortened component always preceded the longer component, response rate decreased in the former. These effects, as well as the increases in response rate following change in component length, seem not to be the product of local contrast effects among components.     

Local contrast and maintained generalization.

Pigeons received variable-interval reinforcement for key pecking during presentations of horizontal and vertical line-orientation stimuli, while pecks during five intermediate orientations were extinguished. Lowest peck rates were observed during presentations of negative stimuli adjacent to the positive orientations while peck rate during 45 degrees (the intermediate negative orientation) was relatively high, i.e., there were negative contrast shoulders. When peck rates were manipulated in the positive orientations, peck rate in neithboring orientations changed in the opposite direction. Contrast shoulders faded after prolonged training. A second type of contrast, local contrast, was correlated with similarity of preceding stimulus and different average peck rates during different stages of the discrimination process. The data suggest that sequential local contrast accompanying the formation of a discrimination contributes to the form of generalization gradients. Blough's model of stimulus control predicts the changes in gradient form described here, but may not accurately depict the underlying process responsible for gradient form.     

The second offspring of General Process Learning Theory: Overt behavior as the ambassador of the mind

Wasserman suggested in a recent book review that the study of intervening cognitive processes represents a current focus of interest in animal learning and that this has led to a revitalization of comparative psychology. An examination of the volume reviewed suggests that he may have overstated the case. Most of the authors to whom he refers expressed dissatisfaction with traditional stimulus-response associationism but few argued for the extreme (information processing) sort of cognitive approach described by Wasserman.     

A comparison of mothers' and fathers' speech to their 3-year-old sons

The language patterns of 10 mothers and 10 fathers with their firstborn 3-year-old sons were compared. Ten-minute mother-son and father-son conversations were recorded independently in the home during a free-play session with standard play mterials. The findings of this study indicate that although mothers and fathers used a similar number of utterances in conversing with their sons over a 10-minute period, their patterns of speech were different on a number of quantitative measures including MLU, MLU of five longest utterances, percent of imperatives, and percent of questions. In general, fathers' communication was viewed as more controlling and involving the child less, while mothers' communication was viewed as more child-centered and involving the child more.     

The effect of school-based kindergarten transition policies and practices on child academic outcomes

This study examined the effect of school-based kindergarten transition policies and practices on child outcomes. The authors followed 17,212 children from 992 schools in the Early Childhood Longitudinal Study-Kindergarten sample (ECLS-K) across the kindergarten school year. Hierarchical linear modeling revealed that the number of school-based transition practices in the fall of kindergarten was associated with more positive academic achievement scores at the end of kindergarten, even controlling for family socioeconomic status (SES) and other demographic factors. This effect was stronger for low- and middle-SES children than high-SES children. For low-SES children, 7 transition practices were associated with a .21 standard deviation increase in predicted achievement scores beyond 0 practices. The effect of transition practices was partially mediated by an intervening effect on parent-initiated involvement in school during the kindergarten year. The findings support education policies to target kindergarten transition efforts to increase parent involvement in low-SES families.     

High-lethality status in patients with borderline personality disorder

Recurrent suicidal behaviors in patients with Borderline Personality Disorder (BPD) are often considered communicative gestures; however, 10% complete suicide. This study seeks to identify risk factors for suicide within a BPD sample by comparing patients with High- and Low-Lethality attempts. BPD attempters (n = 113) were assessed on demographic, diagnostic, and personality variables: clinical symptoms, suicidal behaviors; childhood, family, and treatment histories; social adjustment; and recent life events. Forty-four High-Lethality attempters, defined by a score of 4 or more on Beck's Medical Lethality Scale, were compared to 69 Low-Lethality attempters. Discriminating variables were entered in a multivariate logistic regression model to define predictors of High-Lethality status. High-Lethality attempters were older, with children, less education, and lower socioeconomic class (SES) than Low-Lethality attempters. They were more likely to have Major Depressive Disorder (MDD), co-morbid Antisocial Personality Disorder (ASPD), and family histories of substance abuse. They reported greater intent to die, more lifetime attempts, hospitalizations, and time in the hospital. High-Lethality status was best predicted by low SES, co-morbid ASPD, extensive treatment histories, and greater intent to die. These characteristics resemble profiles of patients who complete suicide, are not specific for BPD, and do not include impulsivity, aggression, or severity of BPD criteria.     

The compensation and capitalization models: A test of two approaches to individualizing the treatment of depression

Despite long-standing calls for the individualization of treatments for depression, modest progress has been made in this effort. The primary objective of this study was to test two competing approaches to personalizing cognitive-behavioral treatment of depression (viz., capitalization and compensation). Thirty-four adults meeting criteria for Major Depressive Disorder (59% female, 85% Caucasian) were randomized to 16-weeks of cognitive-behavioral treatment in which strategies used were selected based on either the capitalization approach (treatment matched to relative strengths) or the compensation approach (treatment matched to relative deficits). Outcome was assessed with a composite measure of both self-report (i.e., Beck Depression Inventory) and observer-rated (i.e., Hamilton Rating Scale for Depression) depressive symptoms. Hierarchical linear modeling revealed a significant treatment approach by time interaction indicating a faster rate of symptom change for the capitalization approach compared to the compensation approach (d = .69, p = .03). Personalizing treatment to patients' relative strengths led to better outcome than treatment personalized to patients' relative deficits. If replicated, these findings would suggest a significant change in thinking about how therapists might best adapt cognitive-behavioral interventions for depression for particular patients.     

EFFECTS OF VIDEO MODELING ON TEACHING BIDS FOR JOINT ATTENTION TO CHILDREN WITH AUTISM

The purpose of this study was to evaluate the effects of video modeling to teach children with autism to initiate bids for joint attention. The video model consisted of a child demonstrating three components of a bid for joint attention with an adult conversational partner: orienting toward the object, emitting a vocal statement, and eye gaze shift toward unique objects in the environment. Results indicated that video modeling alone was effective in teaching all components of joint attention for two of the three children, whereas video modeling plus in vivo prompting was effective for the third participant. Further, bids for joint attention did not generalize across novel items for any of the participants. Results are discussed in terms of the social relevance and validity of the use of video modeling to teach a complex social behavior such as bids for joint attention. Copyright © 2014 John Wiley & Sons, Ltd.     

Around the world,adolescence is a time of heightened sensation seeking and immature self‐regulation

The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries.