The schedule dependency of the signaled reinforcement effect

In Experiment 1, rats leverpressed for food reinforcement on either a variable ratio (VR) 30 schedule or a variable interval (VI) 15-s schedule. One group in each condition received a signal filling a 500-ms delay of reinforcement. This treatment enhanced rates on the VR schedule, and attenuated rates on the VI schedule, relative to the rate seen in an unsignaled control condition. In Experiment 2 there was no delay of reinforcement and the signal and food were presented simultaneously. Attenuated rates of responding were observed on VI schedules with a range of mean interval values (15 to 300 s). Experiment 3 used a range of VR schedules (10 to 150) with simultaneous presentations of signal and food. A signal-induced enhancement of response rate was found at all VR values. In Experiment 4, a signal elevated response rates on a tandem VI VR schedule, but depressed rates on a tandem VR VI schedule, compared to control conditions receiving unsignaled delayed reinforcement. These results are taken to show that the effect of a signal accompanying reinforcement depends upon the nature of the behavior that is reinforced during exposure to a given schedule.     

Rorschach assessment of borderline children

Projective testing may provide the clinician with a valuable context in which childhood borderline conditions may be investigated. The purpose of this study was to determine if Rorschach scores could be useful in diagnosing borderline disorders. Rorschach scores from a group of 13 borderline children and 10 conduct disorder children were compared using a step-down discriminate analysis. The results indicated that children in these two groups could be correctly classified beyond chance levels using Rorschach scores. Three variable, content analysis, human movement, and animal movement were the strongest contributors in separating the two groups. The Rorschach measure of form quality (i.e., adequacy of perception) was notable in that it failed to produce any independent discriminatory power in this analysis. As in the case of adult borderline testing using the Rorschach, novel scoring procedures, used in conjunction with standard scoring procedures may lead to further clarification of childhood borderline disorders.     

Visual Reinforcement Signals Interfere with the Effects of Reinforcer Magnitude Manipulations

Three experiments examined the effect of reinforcement magnitude on free-operant response rates. In Experiment 1, rats that received four food pellets responded faster than rats that received one pellet on a variable ratio 30 schedule. However, when the food hopper was illuminated during reinforcer delivery, there was no difference between the rates of response produced by the two magnitudes of reward. In Experiment 2, there was no difference in response rates emitted by rats receiving either one or four pellets of food as reward on a random interval (RI) 60-s schedule. In Experiment 3, rats responding on an RI 30-s schedule did so at a lower rate with four pellets as reinforcement than with one pellet. This effect was abolished by the illumination of the food hopper during reinforcement delivery. These results indicate that the influence of magnitude is obscured by manipulations which signal the delivery of reinforcement.     

Narcissism as a moderator of the relationship between job characteristics and job reactions

A growing body of research has begun to examine the relationship between narcissism and human behavior in organizations. The research to date, however, has been anecdotal and impressionistic. The present research represents the first attempt to use a questionnaire methodology to examine systematically narcissism as an individual difference variable within an organizational context. Using an interactionist perspective, it is posited that narcissism will moderate the relationship between perceived role and job characteristics and work satisfaction. Data are analyzed from a convenience sample of 272 persons who worked full time and who attended college, using subgroup analysis and moderated multiple regression. Only modest evidence of the predicted moderator effects was found. Explanations for the weak results are offered and three possible modifications for future research are recommended.     

The importance of conduct problems and depressive symptoms in predicting adolescent substance use

The current study assessed the relative importance of conduct problems and depressive symptoms, measured at two ages (11 and 15), for predicting substance use at age 15 in an unselected birth cohort of New Zealand adolescents. Among males, when the relative predictive utility of both conduct problems and depressive symptoms was assessed, only pre-adolescent depressive symptoms were found to predict multiple drug use 4 years later. No predictive relation was found between early symptomatology and later substance use among females. The strongest association between predictors and substance use emerged between age 15 multiple drug use and concurrent conduct problems for both males and females. Finally, both conduct problems and depressive symptoms at age 15 were also found to be associated with concurrent self-medication among females.This work was supported by USPHS grants MH-43746 and MH-45070 from the Antisocial and Violent Behavior Branch of the National Institute of Mental Health to Terrie Moffitt. Bill Henry was funded by a Fulbright Travel Award. The Dunedin Multidisciplinary Health and Development Research Unit is supported by the Medical Research Council and Health Research Council of New Zealand. Appreciation is expressed to the interviewers who collected the data, and to the young New Zealanders who were members of the sample.     

Comparing autistic and normal children along the dimensions of reinforcement maximization, stimulus sampling, and responsiveness to extinction

The purpose of this study was to assess autistic children's ability to maximize reinforcement, sample among available stimuli, and respond to extinction. Responding to five concurrent reinforcement schedules (CRF, FR 2, FR 4, FR 7, and FR 11) was monitored and compared to groups of mental age-matched and chronological age-matched normal children. When a given child consistently selected a given schedule of reinforcement, it was then put on extinction, and both perseveration and responding to the remaining (intact) schedules of reinforcement were monitored. The results showed, first, that while normal children selected the richest schedule of reinforcement, autistics did not maximize reinforcement, typically selecting one of the thinner schedules available. Second, the autistic children sampled less, and less efficiently, than the normal children. Third, the autistic children proved to be much less responsive to extinction, perseverating longer than the normal children before switching to a new reinforcement schedule. Fourth, whenever extinction proved to be a problem in the autistics, it was quickly achieved by a simple change in the stimulus conditions. These results are discussed as possible "keystone" deficits, which may be causally related to many of the behavioral deficits of autism and which might be important target behaviors for treatment.