A comparison of the effects of partial reinforcement schedules using a within-subject serial autoshaping procedure

Three experiments, each using a single group of pigeons, are reported. In Experiment 1 subjects were initially trained with two stimuli, one of which was always followed by food, the other being reinforced according to a 50% partial reinforcement schedule. Subsequently a serial procedure was adopted in which an additional stimulus, C, was consistently followed by the partially reinforced CS. A second additional stimulus, A, was followed on half of its occurrences by the continuously reinforced CS, its remaining presentations being followed by nothing. The rate of autoshaped keypecking was substantially greater during A than during C. In the remaining experiments subjects received first-order conditioning with a single stimulus that was either partially (Experiment 2) or continuously (Experiment 3) reinforced. The stimuli A and C were then again introduced for serial autoshaping. Stimulus A was occasionally paired with the CS and occasionally followed by nothing, whereas stimulus C was always followed by the CS. As in Experiment 1, the rate of responding during A was greater than during C. It is proposed that one influence on the rate of autoshaped keypecking during a CS is the accuracy with which the immediate consequences of that CS are predicted.     

Information Load: A Test of an Inverted-U Hypothesis with Hourly and Salaried Employees

We surveyed 714 hourly and 516 salaried employees of a midwestern telephone company to test the effects of information load on work-related outcomes. Using curvilinear regression analyses, we found support for our hypothesis that employees are less satisfied with outcomes as the load of information deviates positively or negatively from some level. We also predicted, and found, that this quadratic function was more prevalent in the hourly group than in the salaried group. Implications, future research directions, and limitations of the present study are discussed.     

CLINICAL BEHAVIORAL PHARMACOLOGY: METHODS FOR EVALUATING MEDICATIONS AND CONTINGENCY MANAGEMENT

We evaluated methods for comparing the effects of dextroamphetamine (Dexedrine), thioridazine (Mellaril), and contingency management in the control of severe behavior problems. A reversal design was used in which medications were systematically titrated and assessed in unstructured as well as structured settings with three clients. Subsequently, behavioral procedures including timeout, differential reinforcement of other behavior, and visual screening, were used in a multiple-baseline design across settings. The assessment and design methods were useful in comparing the interventions. Dextroamphetamine decreased inappropriate behaviors and improved academic behaviors in one client, but no reliable effects were observed in the other two clients. Thioridazine was variable across clients, settings, behaviors, and dosages. Contingency management produced consistent decreases in inappropriate behaviors and small improvements in academic performance.     

Ear asymmetries in dichotic listening tasks which increase in difficulty

Accuracy and laterality of ear preference in repeating 2, 3 and 4 word pairs (WP) of dichotic stimuli in English and French were determined in 80 right-handed subjects (anglophone/francophone, male/female), who were tested in both their native language (L1) and nonnative language (L2). Relative performance accuracy decreased as a function of word pairs per trial (from 2 to 4) as well as language (from L1 to L2). Right-lateral preference in turn increased as a function of WP (from 2 to 4) as well as language (L1 to L2). Right-ear advantage (REA) in L2 decreased as a function of language proficiency (low to high). REA was observed in over 90% of subjects. A rationale for greater lateralization of L2 performance is offered.     

On the longevity of behavioral interventions for challenging behavior

The capacity for a treatment to maintain its effects over time may be the most critical component of behavioral interventions for challenging behavior as treatments that fail to persist are likely to be of little value to society. We reviewed the quality and quantity of different types of post-intervention data for the treatment of challenging behavior in studies published over the last 7 years. We found that for the majority of participants at least one measure of maintenance, fading, or follow-up was reported but with limited information regarding the quality of those measures. Reports of secondary variables related to post-intervention data (e.g., latency to measurement) were also uncommon. We discuss possible explanations for the paucity of post-intervention data, barriers to obtaining post-intervention data, strategies for obtaining these data, and implications for the external validity of behavioral interventions for challenging behavior. We provide recommendations for increasing the probability that post-intervention data are included in applied research on challenging behavior.