Substitution effects in a generalized token economy with pigeons

Pigeons made repeated choices between earning and exchanging reinforcer‐specific tokens (green tokens exchangeable for food, red tokens exchangeable for water) and reinforcer‐general tokens (white tokens exchangeable for food or water) in a closed token economy. Food and green food tokens could be earned on one panel; water and red water tokens could be earned on a second panel; white generalized tokens could be earned on either panel. Responses on one key produced tokens according to a fixed‐ratio schedule, whereas responses on a second key produced exchange periods, during which all previously earned tokens could be exchanged for the appropriate commodity. Most conditions were conducted in a closed economy, and pigeons distributed their token allocation in ways that permitted food and water consumption. When the price of all tokens was equal and low, most pigeons preferred the generalized tokens. When token‐production prices were manipulated, pigeons reduced production of the tokens that increased in price while increasing production of the generalized tokens that remained at a fixed price. The latter is consistent with a substitution effect: Generalized tokens increased and were exchanged for the more expensive reinforcer. When food and water were made freely available outside the session, token production and exchange was sharply reduced but was not eliminated, even in conditions when it no longer produced tokens. The results join with other recent data in showing sustained generalized functions of token reinforcers, and demonstrate the utility of token‐economic methods for assessing demand for and substitution among multiple commodities in a laboratory context.     

Effects of Intensive Behavioral Treatment for Children With Varying Levels of Conduct Problems and Callous-Unemotional Traits

The purpose of this study was to examine whether callous–unemotional (CU) traits moderated the effects of intensive behavior therapy in elementary school-age children with varying levels of conduct problems (CP). Both treatment response (magnitude of change between pre- and posttreatment) and treatment outcomes (likelihood of normalization from treatment) were examined. Participants were 67 children (n = 49 boys, M_age = 9.6 years) with varying levels of CP and CU who participated in an intensive 8-week summer treatment program (STP) in which behavior therapy was delivered to children in recreational and classroom settings and to parents via weekly parent training sessions. Effects of treatment were measured using parent and teacher ratings of oppositional defiant disorder (ODD), conduct disorder (CD), callous behavior, and impairment. Results showed that CU moderated treatment effects for CD and callous behavior but not ODD or impairment. The moderating effects showed some evidence that participants with high CP and high CU before treatment had better treatment responses (larger change between pre- and posttreatment) but worse treatment outcomes (lower likelihood of normalization after treatment). These results suggest that intensive treatment, such as the STP, may be necessary but not sufficient for children with CP and CU traits.     

Ethnicity and adolescent substance use

This study focuses on diverse ethnic differences among adolescent substance use, utilizing selected items from the Substance Abuse Subtle Screening Inventory-Adolescent version (SASSI-A). Data were gathered from a large-scale, cross-sequential study of adolescents during the 1993-1996 school years. Exploratory analyses were conducted for 3,711 students on the basis of their responses to a self-administered survey. Results indicated significant ethnic and gender differences for specific SASSI-A items and factor scores, with Hawaiian, "Other," and Caucasian students reporting higher scores than Japanese students and greater scores for female than male students. These findings suggest the need to develop culturally sensitive substance use prevention and treatment strategies that should also take gender differences into consideration for adolescents in Hawai'i.     

Cognitive colonialism: Nationality bias in Brazilian academic philosophy

This paper presents the results of an experiment designed to test for nationality bias among members of the Brazilian philosophical community. Faculty members and postgraduate students from philosophy departments at seven Brazilian universities evaluated texts attributed to authors of European and Latin American nationalities. Results showed a clear preference for French nationality over Brazilian. They were inconclusive, however, when contrasting other Latin American nationalities with European nationalities, which likely relates to the academic background of the participants. These overall results support the claim that Brazilian academic philosophers are highly critical of Brazilians who produce theories of their own. The paper calls on philosophers to carefully consider the ways in which Eurocentrism impacts their very ability to reason.     

Effect of sex education on the sexual and contraceptive practices of female teenagers in Mexico City

After reviewing the literature on the relationship between sex education and sexual and contraceptive behavior, the National Research Council (1987) recently concluded that the existing evaluation of the effects of sex education on sexual and contraceptive practice is helpful but not sufficient. 1 possible explanation for the different results obtained are the diverse sociodemographic characteristics of the sample(s) of teens under consideration. Another aspect which might account for the differences seen in the literature focuses on the areas covered in the course. In Mexico, no studies have been undertaken which deal with the relationship between sex education and sexual and contraceptive behaviors. A study carried out with 392 adolescent females ages 16-17 of lower and middle lower socioeconomic status showed that merely attending a sex education course did not affect the initiation or continuation of sexual activity, contraceptive behavior, or even the perception of accessibility to contraception. Providing information on sexuality, partner relationships, and where contraception can be obtained does not appear to have any effect on sexual activity. Receiving information on pregnancy prevention and obtaining contraceptives was found to be related to contraceptive use. Although less dramatic, information about partner relationships and sexuality produced increases in contraceptive use.     

Weight status misperception among Mexican young adults

Individuals who misperceive their body size are at risk for eating disorders, unhealthy weight control practices, and obesity-related diseases. This study assessed the prevalence and demographic, behavioral, and psychosocial correlates of agreement between perceived (self-reported) and actual (measured) body mass index categories in a sample of Mexican college applicants aged 18-20 years (N=3622; 52% female). Under two thirds (63.1%) accurately reported their weight status categories. Reporting accuracy was lower among overweight and obese participants. In multivariate analyses, overestimating was associated with female gender, younger age, lower level of parent education, and more hours of daily TV viewing; underestimating was associated with male gender and older age. In within-gender analyses, overestimating was associated with hours of TV among men and underestimating was positively associated with depressive symptoms among women. This study adds to a growing international literature on body weight status misperception among adolescents and young adults.     

Effect of Nonspecific Chronic Low Back Pain on Walking Economy: An Observational Study

The authors investigated the effects of chronic low back pain (LBP) and walking speed (WS) on metabolic power and cost of transport (CT). Subjects with chronic nonspecific LBP (LBP group [LG]; n = 9) and healthy (control group [CG]; n = 9) were included. The test battery was divided into 3 blocks according to WS as follows: preferred self-selected speed (PS), and lower and higher than the PS. In each block, the volunteers walked 5 min, during which oxygen consumption was measured. Although without differences between groups, the LG had CT lower in slower speeds than in faster speeds. Walking speed affected CT only in the LG, which the group had the greatest walking economy at slower speeds.     

What does doodling do?

Doodling is a way of passing the time when bored by a lecture or telephone call. Does it improve or hinder attention to the primary task? To answer this question, 40 participants monitored a monotonous mock telephone message for the names of people coming to a party. Half of the group was randomly assigned to a ‘doodling’ condition where they shaded printed shapes while listening to the telephone call. The doodling group performed better on the monitoring task and recalled 29% more information on a surprise memory test. Unlike many dual task situations, doodling while working can be beneficial. Future research could test whether doodling aids cognitive performance by reducing daydreaming. Copyright © 2009 John Wiley & Sons, Ltd.     

Mood state indicators for adolescent athletes based on POMS multidimensional model

In this paper, we offer a short version of the POMS, with only 33 items, designed to apply to young Spanish athletes. One hundred and six male soccer players, aged 14 and 15 years, participated in the study. In order to select the proposed items, we tried to maximize three criteria: (1) items should be understood by subjects, (2) items should be perceived as conceptually similar as possible to the meaning of their respective factors, and (3) every factor should contain at least 4 items. To meet the second criterion, PROXSCAL scaling procedure was used, which allowed retaining the items closest to the meaning of each factor. All goodness-of-fit indexes were satisfactory in all the proximity analyses performed. In the proposed POMS version, the 33 items refer to seven mood factors, as follows: Tension (4 items), Depression (9 items), Anger (4 items), Vigour (4 items), Fatigue (4 items), Confusion (4 items), and Friendliness (4 items).