INCREASED PEER-TEACHING WITH GROUP-ORIENTED CONTINGENCIES FOR ARITHMETIC PERFORMANCE IN BEHAVIOR-DISORDERED ADOLESCENTS1

Group-oriented contingencies were applied to increase the arithmetic problem-solving rates of four behavior-disordered adolescent residents in a psychiatric hospital. The experiment followed an ABAC reversal design consisting of baseline conditions (A₁ and A₂), and cumulative (B) and mixed (C) interdependent group-oriented contingency conditions. Under the cumulative arrangement, the subjects earned five cents for every correctly solved multiplication problem. The same conditions were in effect with the mixed contingency, except that each subject was required to work at least three problems before any subject could earn money. The results indicated consistent increases in the subjects' arithmetic computation rates as a function of the group-oriented contingencies. Concurrent observations were made across the four conditions of the experiment on four categories of the subjects' verbalizations: antecedent peer-teaching, consequent peer-teaching, positive statements, and negative statements. The subjects' rates of antecedent peer-teaching verbalizations covaried with the group-contingency-induced increases in their levels of computation behavior. The majority of the verbalization involved answers to number fact questions or redirecting peers to engage in on-task activities. The three other categories of the subjects' verbalizations that were observed—consequent peer-teaching, positive statements, and negative statements—were not found to covary with the subjects' altered rates of computation behavior.     

Predictability of chronic intermittent stress: effects on sympathetic-adrenal medullary responses of laboratory rats

This experiment involved an examination of sympathetic-adrenal medullary responses of laboratory rats following exposure to chronic intermittent stress. Animals were assigned at random to one of three groups: (i) controls, handled briefly each day; (ii) restraint stress (RS), restrained for 30 min per day; or (iii) variable stress (VS), exposure to restraint, cold swim, or intermittent footshock during one of five time periods each day. On the 26th day, rats were prepared with chronic tail artery catheters for remote sampling of blood and direct measurement of mean arterial pressure and heart rate. On Day 28, rats of each group were exposed to 30 min of restraint stress and timed blood samples were collected and later analyzed for content of norepinephrine (NE) and epinephrine (EPI). VS rats gained significantly less body weight compared to control and RS rats. Basal measures of blood pressure and heart rate and of plasma NE and EPI were comparable for rats of the three groups. The plasma catecholamine responses to restraint stress on Day 28 were significantly reduced in RS and VS rats compared to first-time stressed controls. These findings suggest that predictability of the type of stressor and the time of its occurrence does not influence the pattern of diminished sympathetic-adrenal medullary responses of animals exposed to chronic intermittent stress.     

Control-related beliefs and depressive symptoms in clinic-referred children and adolescents: developmental differences and model specificity

The contingency-competence-control (CCC) model links contingency and competence beliefs to perceived control and, in turn, to depression. However, a developmental perspective suggests that noncontingency may be too abstract a concept to be directly tied to depression before adolescence. We tested the CCC model and this developmental notion, using structural equation modeling, with 360 clinic-referred 8- to 17-year-olds. The CCC model fit the data well for the full sample accounting for 46% of the variance in depression. Separate analyses by age group placed perceived contingency in the best-fit model for adolescents (ages 12-17 years) but not for children (8-11 years). This suggests that abstract cause-effect concepts may have more direct affective impact after the cognitive changes of adolescence (e.g., formal operations) than before. Finally, the CCC model accounted for much more variance in depression than conduct problems, suggesting diagnostic specificity.     

Emotional health predictors of substance use initiation during middle school

This study aimed to evaluate whether emotional health factors, including anxiety and depression, stress, and social support, are associated with earlier youth initiation of alcohol and illicit substances during middle school (from the sixth to the eighth grade). Data for this study were from the Developmental Pathways Project, a longitudinal study of 521 youth sampled from the Seattle Public Schools. Discrete time survival analyses were used to assess the effects of depression, anxiety, stress, and support on initiation of substance use, measured every 6 months at five time points between sixth and eighth grade. Youth who had initiated prior to sixth grade had significantly higher levels of depressive symptoms. In multivariate survival analyses controlling for child race/ethnicity, gender, and socioeconomic status, and accounting for conduct problems, youth who reported higher levels of separation anxiety/panic symptoms were at decreased risk for early alcohol initiation. Children with higher levels of perceived teacher support had a significantly lower risk of alcohol initiation during early follow-up periods. Recent stressful life events in Grade 6 were associated with significantly greater risk of initiating an illicit substance by Grade 8. The current findings highlight the role of stress in the initiation of illicit substance use and suggest that teacher support is associated with lower risk for very early alcohol use. Future research examining anxiety as a predictor of substance use should distinguish between subtypes of anxiety.     

Sales Technology Applications: Self-Paced Video Enhanced Training: A Case Study

Video enhanced sales training (VET) is being adopted by a substantial number of firms. The reported advantages of video enhanced programs are lower costs and results-oriented training. The major characteristics and applications of this sales training technology are presented. The application of video enhanced training at Motorola Inc. is described. Results indicate that video enhanced training is a promising technological application that improves sales training effectiveness.     

Food deprivation: Effects on the predatory behavior of southern grasshopper mice (Onychomys torridus)

The southern grasshopper mouse (Onychomys torridus) is a predatory and aggressive rodent native to the semi-arid scrub deserts of the southwestern United States and northern Mexico. Its natural diet consists primarily of arthropods and small vertebrates. In this study, we have evaluated the effects of food deprivation on the predatory behavior of adult male and female grasshopper mice to crickets (Acheta domesticus) and laboratory mice (Mus musculus). Subjects that were food-deprived for 48 hours spent more time eating dead but not living crickets than did controls that were provided free access to laboratory chow. There were no sex differences in the predatory behavior of grasshopper mice to living or dead crickets. Food deprivation also influenced the predatory behavior of grasshopper mice toward laboratory mice. With laboratory chow available ad lib, 6 of 43 (14%) male and 22 of 45 (49%) female grasshopper mice killed and ate laboratory mice within 48 hours of pairing. When deprived of food for 48 hours, 16 of 36 (44%) males and 15 of 19 (79%) females that did not kill in the previous experiment killed and ate laboratory mice. We concluded that food deprivation and type of prey are two variables which influence the frequency and intensity of predatory behaviors of grasshopper mice.     

Regulation of Peripheral Catecholamine Responses to Acute Stress in Young Adult and Aged F-344 Rats

Young adult (3-month-old) and aged (24-month-old) Fischer-344 male rats received i.v. infusions of 3H-labeled norepinephrine (NE) and epinephrine (EPI) to examine the effects of aging on the neuronal uptake of NE and sympathoadrenal release of NE and EPI. Spillovers of NE and EPI into plasma and their clearance from the circulation were estimated from plasma concentrations of endogenous and 3H-labeled NE and EPI. The efficiency of neuronal uptake was assessed from changes in plasma clearance of NE and concentrations of its intraneuronal metabolite, dihydroxyphenylglycol (DHPG), during immobilization stress or neuronal uptake blockade with desipramine. Stress-induced increases in plasma NE and higher plasma NE concentrations in aged compared to young adult rats were due to both decreases in NE clearance and increases in NE spillover. EPI spillover and clearance were reduced in aged compared to young adult rats, so that plasma EPI levels did not differ between groups. Young adult and aged rats had similar desipramine-induced decreases in NE clearance, whereas desipramine-sensitive decreases and stress-induced increases in plasma DHPG were larger in aged rats. This indicates that neuronal uptake is intact and that increased NE spillover at rest and during stress in aged rats reflects increased NE release from sympathetic nerves. The results show that aging is associated with divergent decreases in EPI release from the adrenal medulla and increases in NE release from sympathetic nerves. Increased plasma concentrations of NE in aged compared to young adult rats also result from decreased circulatory clearance of NE, but this does not reflect any age-related impairment of NE reuptake.     

Shared maternal influences in the development of high blood pressure in the spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rat strains.

The influence of maternal environment on the development of high blood pressure in spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rats was examined using the technique of reciprocal cross-fostering. Previous experiments from this laboratory demonstrated that adult blood pressures of the SHR and SS/Jr strains were significantly attenuated when hypertensive-strain pups were fostered to a dam of the respective normotensive control strain during the preweaning period. In this study, SHR and SS/Jr pups were assigned to either a cross-fostered (fostered to a dam of the opposite hypertensive strain) or control-reared condition within 24 h of birth. Adult resting blood pressures were similar in control and cross-fostered SHR rats and in control and cross-fostered SS/Jr rats. Heart rates and heart, adrenal, and kidney weights were also similar in control and cross-fostered rats of each strain. However, body weights of SHR rats reared by an SS/Jr dam were somewhat lower compared to control-reared SHR rats. These data indicate that the maternal environments provided by SHR and SS/Jr mothers are similar in some way such that they permit the development and full expression of the hypertensive phenotype in both same-strain and opposite-strain pups.     

Can we trust parent reports in research on cultural and ethnic differences in child psychopathology? Using the bicultural family design to test parental culture effects

Research comparing cultural and ethnic groups on child psychopathology has relied heavily on parent reports. But don't parents' own cultural backgrounds bias their reports, undermining valid assessment of actual child behavior? The question is hard to address because parent and child culture tend to be confounded. To solve this problem, we assembled an unusual but heuristically valuable sample: 50 bicultural families, each with an ethnic Thai parent reared in Thailand and a Caucasian parent reared in the U.S. Parents in each pair independently completed standardized problem checklists on the same child in their family. Across all 10 empirically derived problem syndromes, no parental culture effect was either significant or larger than "small," by Cohen's (1988) standards; across all 140 specific problems, the mean percent of variance accounted for by parent culture was less than 1%. Results do not point to a biasing effect of parental culture.     

Alcoholism, drug abuse, and the homeless.

Credible estimates of the prevalence of alcohol and drug abuse suggest that alcohol abuse affects 30% to 40% and drug abuse 10% to 15% of homeless persons. A review of policies that address substance abuse among the homeless finds that interventions alternate between control and rehabilitation. However, the unique needs of a changing homeless population require an integration of alcoholism and drug abuse recovery services with programs for women, adolescents, and the mentally ill. Alcohol- and drug-free housing is essential to support and maintain recovery. Psychology can contribute in the development of effective programs for homeless individuals struggling with addiction and alcoholism.