The square search test in connection with acoustic evoked brain stem potentials

A random sample of 15 patients suffering from multiple sclerosis without acute episodes and at least partially able to work, shows to a high degree of statistical certainty that reduction in amplitude of acoustically evoked brain stem potentials (BAEP) is closely linked with beta-weighted performance value of the square search test (QSP).     

Measures of observer agreement when binomial data are collected in free operant situations

This paper examines a model and defines reasonable assumptions underlying different measures of observer agreement for categorical data collected in free operant situations. It is assumed that two or more observers classify operant behaviors of subjects into occurrences and nonoccurrences by recognition by validated response classes (categories) such that the rates of false positives and observer biases are acceptably low. Thus errors are mostly omissions, i.e., failing to observe events that occur. Four alternative cases are derived, together with formulas for calculating significance tests, variances, and standard errors, three of which do not depend on knowledge of the proportion of time points at which the event does not occur.We wish to acknowledge NICHD Grant HD-10570, The Neuropharmacology of Developmental Disorders, George Breese, Ph.D., and C. T. Gualtieri, M.D., Principal Investigators; NIEHS Grant ES-01104; USPHS Grant HD-03110; and MCH Project 916 to the Division for Disorders of Development and Learning.     

Reinforcement of eye movement with concurrent schedules

Human macrosaccadic eye movements to two areas of a four-dial display were conditioned by concurrent variable-interval schedules of signals. Reinforcers (signals) were delivered to the two right-hand dials on one schedule and to the two left-hand dials on another, independent schedule. The use of a changeover delay between crossover eye movements and reinforcement had the effect of changing the pattern of scanning from fixating four dials in succession or in a Z-shaped pattern to scanning vertically the dials on either side with fewer crossovers. In the presence of a changeover delay, subjects matched relative eye-movement rates and relative reinforcement rates on each schedule. Rate of crossover eye movements, with a changeover delay in effect, was also inversely related to the difference in reinforcements arranged by the concurrent schedules. The results suggest that for stimuli whose critical components are arranged spatially, conditioned eye movements play an important part in selective stimulus control.     

Main and interaction effects of metallic toxins on classroom behavior

This study investigated the relationships of metal levels and metal combinations to children's classroom behavior. Hair-metal concentrations of lead, arsenic, mercury, cadmium, and aluminum were determined in 80 randomly selected elementary-age children, who were also rated by their classroom teacher on the Walker Problem Behavior Identification Checklist (WPBIC). Parents were interviewed to control for confounding variables that may have affected behavioral development. Regression analysis indicated that the set of metals was significantly related to increased scores on four of the five WPBIC subscales and on the total scale, with lead being a major contributor to four of the six dependent measures. Metal combinations were significantly related to increased scores on the WPBIC subscales measuring acting-out, disturbed peer relations, and immaturity, and on the total scale. A continuing reexamination of metal poisoning concentrations is needed because metal levels and metal combinations previously thought harmless may be associated with nonadaptive classroom behavior.     

Facilitation of memory for extinction of drug-induced conditioned reward: role of amygdala and acetylcholine

These experiments examined the effects of posttrial peripheral and intra-amygdala injections of the cholinergic muscarinic receptor agonist oxotremorine on memory consolidation underlying extinction of amphetamine conditioned place preference (CPP) behavior. Male Long-Evans rats were initially trained and tested for an amphetamine (2 mg/kg) CPP. Rats were subsequently given limited extinction training, followed by immediate posttrial peripheral or intrabasolateral amygdala injections of oxotremorine. A second CPP test was then administered, and the amount of time spent in the previously amphetamine-paired and saline-paired apparatus compartments was recorded. Peripheral (0.07 or 0.01 mg/kg) or intra-amygdala (10 etag/0.5 microL) postextinction trial injections of oxotremorine facilitated CPP extinction. Oxotremorine injections that were delayed 2 h posttrial training did not enhance CPP extinction, indicating a time-dependent effect of the drug on memory consolidation processes. The findings indicate that memory consolidation for extinction of approach behavior to environmental stimuli previously paired with drug reward can be facilitated by posttrial peripheral or intrabasolateral amygdala administration of a cholinergic agonist.     

Young adults with intellectual and other developmental disabilities acquire vocational skills with video prompting

Students with intellectual and other developmental disabilities often require substantial support to acquire the skills needed to secure work experience and paid employment. Prior findings suggest that video prompting is likely to be an effective and feasible strategy for establishing such skills. To evaluate this possibility in a special education transition program, we examined the effectiveness of a video prompting procedure in teaching 8 young adults with developmental disabilities to perform job-related tasks (doing laundry, checking in to work, vacuuming, stripping bed). The intervention was effective with all participants. The skills maintained over 3 months, and the participants performed the tasks accurately in a new setting with different materials. Participants were reportedly satisfied with the intervention and deemed it easy to use.     

Ultimate, provisional, and personal meaning of life: differences and common ground

Building on Viktor Frankl's clinical approach of Logotherapy and the works of subsequent theoreticians, three types of meaning of life were theoretically derived and empirically investigated, Ultimate, Provisional, and Personal meaning. These types were characterized, first, by the amount of agreement of subjects, second, by sources of Life Meaning, which were assessed by content analyses, third, by correlations, and fourth by prediction with ratings of important life concepts from the domains of Well-being, Religiosity, and Prosocial Behavior. 192 German adults, 45 men and 147 women, whose M age was 31.6 yr. (SD = 11.9), participated. Analysis indicated different sources for the Ultimate meaning compared with the other meaning types, which seem to display more similarities with each other. Other important life concepts, such as Belief, Harmony, Happiness, and Human Goodness were related to the investigated types of meaning of life. Some implications for clinical applications, research perspectives, and Positive Psychology are discussed.     

Getting groups to develop good strategies: Effects of reflexivity interventions on team process,team performance,and shared mental models

This study examines the effect of guided reflection on team processes and performance, based on West’s (1996, 2000) concept of reflexivity. Communicating via e-mail, 49 hierarchically structured teams (one commander and two specialists) performed seven 15 min shifts of a simulated team-based military air-surveillance task (TAST) in two meetings, a week apart. At the beginning of the second meeting, teams were assigned either to a reflexivity (individual or group) or to a control condition. Results show that reflexivity enhanced performance, the link between reflexivity and team performance being mediated by communication and implementation of strategies as well as by similarity of mental models. Contrary to expectations, individual reflexivity was superior to group reflexivity. Additional analyses suggested that group reflexivity decreased the commanders’ active behavior and increased discussion of strategies that were too general to be helpful. Results point to the usefulness of reflexivity as a generic intervention but underscore the importance of focusing on strategies that are task-specific.