Role of the striatal cholinergic system in the regulation of learned manipulation in rats

The experiments were performed on adult Wistar male rats trained to push with the forepaw on a fixed piston inside a narrow tube. It was found that after localized intracerebral injection of a cholinergic antagonist into the dorso-lateral (but not medial) neostriatum (i.e., the caudato-putamen) the behavioral performance requiring brief innate movements remained unchanged, but the performance requiring a prolonged pushing movement (> 50 msec) became disrupted. Microinjection of carbacholine (0.03-3 μ g/1 μ1) did not affect the performance of the acquired movements, whereas scopolamine (3 μ g/1 μ1) led to the significant decrease in pushing time. We conclude that changes in the state of the dorso-lateral neostriatal cholinergic system result only in disturbances of the sensory-controlled component of a complex instrumental movement. The 1994 Pavlovian Society Young Investigator Awardee was Nadezda Dubrovskaya, first author of this paper, which was presented at the annual meeting of the Pavlovian Society, July 3, 1994, in Prague, Czech Republic.     

Evaluating children's mental health service systems: An analysis of critical behaviors and events

A lack of studies which evaluate system change by tracking client outcomes is noted in the children's mental health area. This deficit may be a result of the inability of researchers to define outcomes and to draw conclusions about which measures reflect the efficacy of services and service delivery systems. This paper reviews five social validation surveys which examined children's mental health outcome measures. Based on the results of the five surveys, a model of critical behaviors and events is presented. This model will assist evaluators and researchers in understanding which critical events and behaviors should be measured to assess the impact of community-based mental health services for children.     

Effects of diagnostic classification systems on clinical hypothesis-generation

In this study it was determined whether (a) classification as opposed to absence of classification has an effect on the quality of clinical hypotheses (b) the DSM-III-R and the CBCL have a different effect on the quality of clinical hypotheses, and (c) the potential difference between the DSM-III-R and the CBCL is moderated by the different number of syndromes identified by these systems. To investigate these questions, an experiment was conducted in which 86 clinicians generated hypotheses for six cases. The clinicians were divided into a DSM-III-R, a CBCL, and a control group. Of the six cases, two were classified by both classification systems as one syndrome, two were classified as one syndrome by the DSM-III-R but as two syndromes by the CBCL, and two were classified as two syndromes by the DSM-III-R but as one syndrome by the CBCL. The quality of the hypotheses was determined by means of four dependent variables selected from an overview of qualitative criteria: explanatory value, redundancy, possibility of operationalization, and specificity. No differences between the CBCL and the control groups were found. The DSM group performed better than the control group regarding explanatory value and redundancy. The DSM-III-R group also scored better than the CBCL group regarding explanatory value, particularly when the number of identified syndromes was two for the CBCL and one for the DSM-III-R.     

Attention demands of movements as a function of their duration and velocity

The attention demands of initiating and controlling discrete movements were examined as a function of their movement time (MT) and average movement velocity. Experiment 1 showed that the attention required to execute a movement decreased as MT decreased, although Experiment 2 through independently manipulating MT and movement velocity, revealed that movement velocity is the key determiner of attention demands rather than MT. The attention demands of preparing a high velocity movement are greater than during its execution with the reverse being the case for relatively slow velocity movements. The results are compatible with the view that it is the initiation of error corrections that are attention demanding (Keele 1973).     

Sensitivity of 5- and 7-month-old infants to pictorial depth information

An Ames (1951, Psychological Monographs, 65(1, Whole No. 324)) static trapezoidal window, under monocular view, was used to test young infants' responsiveness to pictorial depth. When adults view this display monocularly with the smaller side of the window rotated toward them, they report that the orientation of the display becomes ambiguous: When the head is moved, the window may appear to be in the fronto-parallel plane or either side may appear closer. The 7-month-olds we tested appeared to experience a similar ambiguity; they reached to the near side of the rotated trapezoidal window with significantly less consistency or directedness than infants in a control group tested with a rotated object that lacked pictorial depth information. When 5-month-olds were tested, however, they reached with equal consistency to the closer side of the trapezoidal window and of the control display, apparently uninfluenced by the pictorial depth information available in the trapezoidal window. Thus, sensitivity to the pictorial information for depth that is present in the trapezoidal window appears to develop after the age of 22 weeks.     

Tests for stability in linear structural equation systems

Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.     

An observational case study of failure in social problem-solving

An observationally based assessment of social problem-solving skill was contrasted with more traditional testing methods. A preschool child with low social success was chosen for a demonstration profile analysis. The relative frequencies of the social goals, strategies, and targets shown by this child during free play were plotted in relation to that of his same-sex peer group. Parallel profiles of his relative success with specific goals, strategies, and targets were also constructed and compared to relevant group means and standard deviations. Specific social problem-solving strengths and weaknesses were identified from these profiles, using both intra- and interindividual analyses. The benefits and limitations of this approach for measurement and treatment of social problem-solving deficits were discussed.     

Analysis of the elements of attention: A neuropsychological approach

A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.     

The role of the psychologist expert witness: Provider of perspective and input

The definition and role of the expert witness is reviewed. Two conceptual systems for viewing the world, the scientific method and the adversarial system, are compared. The reconciliation and integration of these two discrepant systems are discussed in terms of input versus outcome. The rules of evidence, as well as problems of communication between the systems, are reviewed with the aim of providing expert witnesses with a better understanding of effective testimony. Finally, collaboration between the two systems is called for in order to provide guidelines for both neuropsychologists and attorneys.     

Interpersonal problem solving: An intervention program for preschool children

The purpose of the present study was to evaluate the effectiveness of an intervention program designed to train preschool children in interpersonal problem solving skills. Forty preschool age children were randomly assigned to an experimental or control group. Experimental subjects were trained in interpersonal problem solving skills for ten weeks, four days per week, for a total of 10–13 hours. Problem-solving skills were assessed at pretest, posttest, and three months after training was completed. Seventy-eight percent of the children who participated in pretest and posttest were tested at follow-up. Results indicated that the experimental group, compared to the control group, showed a significant increase in both cognitive—verbal and behavioral interpersonal problem-solving skills from pretest to posttest and that these changes were maintained at follow-up testing. Discussion focuses on suggestions for future research and implications for applied settings.