Secobarbital and perceptual processing

An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated.     

On becoming a school psychologist: A semiautobiographical account

As an example of the development of an early school psychology program in the Southwest, the beginning of Child Study and Consultation Service is described. The unique aspect of this program undoubtedly had to do with its relationship to a demonstration mental health center and a consultation program started in several elementary school districts in the area. Beginning with a consortium of five school districts, it was later expanded to include 16 school districts with a staff of 15 doctoral-level school psychologists. This account also describes the author's involvement with the Division of School Psychology and some of the major issues facing the division in the late 1950s and 1960s. An attempt is made to show how the author's educational and work experiences contributed to the philosophy, policies, and practices of school psychology.     

Selective attention and rehearsal in the auditory short-term memory task performance of poor and normal readers

The performance of poor and normal sixth-grade readers was compared on an auditory short-term memory task in two studies. In the first study, the effects of distraction, list length, and speed of stimulus presentation were investigated to test the hypothesis that the performance of the poor readers is affected by deficits in selective attention. Group differences in performance, however, were obtained for both distraction and no-distraction conditions. The second experiment examined the hypothesis that group differences may reflect differences in the use of rehearsal. In the second experiment, half the reading-disabled children and half the controls were provided with rehearsal training prior to completing the same short-term memory task a second time. Rehearsal training resulted in improved performance relative to children who were not trained; however, there was no rehearsal training x reading group interaction. The poor readers continued to show deficits in performance relative to the performance of control children. The results of these two studies suggest that deficits observed for poor readers on short-term memory tasks may reflect processing difficulties in some area that precedes rehearsal and affects performance under both distraction and no-distraction conditions.The authors wish to express their thanks to the Sachem School District and Betty Gould, Nicholas Opinanate, and Guy Barber for their unlimited cooperation, and to John Neale for very helpful discussions of a number of issues in this paper.     

Development of differences in response latencies to right and left visual fields

Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.     

Representation of linear orders

Two binary classification tasks were used to explore the associative structure of linear orders. In Experiment 1, college students classified English letters as targets or nontargets, the targets being consecutive letters of the alphabet. The time to reject nontargets was a decreasing function of the distance from the target set, suggesting response interference mediated by automatic associations from the target to the nontarget letters. The way in which this interference effect depended on the placement of the boundaries between the target and nontarget sets revealed the relative strengths of individual interletter associations. In Experiment 2, students were assigned novel linear orders composed of letterlike symbols and asked to classify pairs of symbols as being adjacent or nonadjacent in the assigned sequence. Reaction time was found to be a joint function of the distance between any pair of symbols and the relative positions of those symbols within the sequence. The effects of both distance and position decreased systematically over 6 days of practice with a particular order, beginning at a level typical of unfamiliar orders and converging on a level characteristic of familiar orders such as letters and digits. These results provide an empirical unification of two previously disparate sets of findings in the literature on linear orders, those concerning familiar and unfamiliar orders, and the systematic transition between the two patterns of results suggests the gradual integration of a new associative structure.     

Cognitive dysfunction in compulsive checkers: Further explorations

Recent evidence suggests a relationship between certain memory deficits and compulsive-checking behavior. The present study explores this relationship in the context of several additional memory capacities not yet investigated. Using the Maudsley Obsessional-Compulsive Inventory and the Everyday Checking Behavior Scale four groups of Ss were identified: (1) frequent checkers, (2) occasional checkers, (3) infrequent checkers and (4) noncheckers. Consistent with previous research, a memory-for-actions task indicated a deficit among compulsive checkers. Furthermore, checking status was found to be negatively related to memory functioning as measured by the Wechsler Memory Scale (WMS) and the Cognitive Failures Questionnaire (CFQ). This memory deficit was most pronounced on the Logical Memory subtest of the WMS. Checkers appear to have difficulty recalling details of meaningfully linked sequences, either presented in narrative form or engaged in personally. Although the reasons for these checking-related deficits are not clear, a complete understanding of checking phenomena will involve an appreciation of the role played by memory deficits.     

THE IMPACT OF PSYCHOLOGICAL TESTING ON EDUCATIONAL AND PERSONNEL SELECTION IN AFRICA

Psychological testing for Education and Personnel selection is of great importance in the efforts by many African countries to ensure that suitable candidates are selected for education beyond the primary school level and for training for different employment. Major investigations directed to this need have been in the area of adapting tests already available in Western countries and determining the reliability and predictive validity of battery of tests so adapted and their tryout in African schools to determine their efficiency as tools for selection.     

Reactivity and unreliability of husbands as participant observers

This study examined the reliability and reactivity of participant observation. Twelve couples engaged in two discussions in a laboratory, one on a conflict topic and one on a consensus topic. For the eight couples in the experimental sequences, a baseline discussion was followed by participant observation in which the husband recorded his wife's use of I while continuing to converse. The four couples in the control sequences conversed without participant observation. Compared to observations made by a trained observer, the husbands were unreliable observers, underestimating their wives' use of I. Participant observation was reactive (P<.01), with more wives decreasing their use of I in the experimental sequences than in the control sequences (p<.094). The topic of discussion did not differentially influence reliability or reactivity.This research was conducted as the first author's independent doctoral research project. We extend gratitude to the Research Council of the University of North Carolina at Greensboro for Grant 0-2-110-218-XXXXX-7548; the Statistical Consulting Center of the University of North Carolina at Greensboro; two anonymous reviewers; and our research assistants, Suzanne Brannon, Ben Hardie, Kathy Lindamood, Amy Mitchem, Regina Pierce, and Elga Wulfert. Portions of this paper were presented at the meeting of the Association for Advancement of Behavior Therapy, Washington, D.C., December 1983.     

Least squares metric,unidimensional unfolding

The partial derivatives of the squared error loss function for the metric unfolding problem have a unique geometry which can be exploited to produce unfolding methods with very desirable properties. This paper details a simple unidimensional unfolding method which uses the geometry of the partial derivatives to find conditional global minima; i.e., one set of points is held fixed and the global minimum is found for the other set. The two sets are then interchanged. The procedure is very robust. It converges to a minimum very quickly from a random or non-random starting configuration and is particularly useful for the analysis of large data sets with missing entries.This paper benefits from many conversations with and suggestions from Howard Rosenthal.