Maladjustment in statistical minorities within ethnically unbalanced classrooms

Ascertained if being a member of a statistical minority influences children's adjustment in school, as measured by the AML, a teacher-administered adjustment rating scale. Teachers from a southwest school district evaluated elementary students on aggressive, acting-out behaviors, moody-internalized behaviors, and learning difficulties. Analyses conducted on 376 students revealed significant effects of statistical minority status on certain dimensions of adjustment ratings for both Hispanic and Anglo students. Hispanic students in the statistical minority received poorer ratings on the moodiness dimension of the AML than nonminority Hispanic students. Anglo students in the statistical minority received poorer ratings on the aggression dimension of the AML than nonminority Anglo students. These results were interpreted in terms of cultural differences in coping with statistical minority status. Traits commonly exhibited within a culture may intensify and be perceived as maladaptive when stress resulting from being a minority occurs. Implications of the finding that statistical minority status within the school environment influences adjustment are discussed.     

A componential analysis of pacemaker-counter timing systems

Why does counting improve the accuracy of temporal judgments? Killeen and Weiss (1987) provided a formal answer to this question, and this article provides tests of their analysis. In Experiments 1 and 2, subjects responded on a telegraph key as they reproduced different intervals. Individual response rates remained constant for different target times, as predicted. The variance of reproductions was recovered from the weighted sum of the first and second moments of the component timing and counting processes. Variance in timing long intervals was mainly due to counting error, as predicted. In Experiments 3-5, unconstrained response rate was measured and subjects responded at (a) their unconstrained rate, (b) faster, or (c) slower. When subjects responded at the preferred rate, the accuracy of time judgment improved. Deviations in rates tended to increase the variability of temporal estimates. Implications for pacemaker-counter models of timing are discussed.     

On the relation between metacontrast masking and suppression of visible persistence

Does the introduction of additional contours in a display sequence (an operation known to reduce the strength of suppression in metacontrast) also reduce suppression of visible persistence? In three experiments, duration of visible persistence was estimated by a method in which successful performance depends on the temporal integration of a pattern whose elements are displayed in two successive frames. In this procedure, the arrival of the trailing frame is known to exert a suppressive influence on the visible persistence of the leading frame. Embedding the elements of the leading frame within additional contours (a line grid) reduced the degree of suppression exerted by the trailing frame. This did not occur when the grid was part of the trailing display. We conclude that suppression of visible persistence and metacontrast masking belong to the same class of events.     

On the intricacies involved in the study of similarity judgments: comment on Ritov, Gati, and Tversky

The purpose of this comment is to point out some potential pitfalls in the study of similarity judgments, particularly with regard to comparison of similarity judgments between modalities. These are discussed in the context of the article by Ritov, Gati, and Tversky (1990).     

Retraction of Ross and LoLordo findings concerning blocking in serial feature-positive discriminations.

Findings concerning the effectiveness of stimuli from various conditioning procedures in blocking conditioned excitation and occasion-setting functions of an added stimulus in a serial feature-postive discrimination training procedure (LoLordo & Ross, 1987; Ross & LoLordo, 1986, 1987) are retracted. Videotapes on which the published data were based were rescored by 2-5 people, most of whom were uninformed about group memberships of the subjects. In no case did the rescoring confirm any of the orginal findings of blocking. Possible factors contributing to the discrepancies are discussed. The experiments should be repeated with feature stimuli that are less similar to each other and with several scorers, at least one of whom is unaware of the group assignment of the subjects.     

Discriminative properties of morphine that modulate associations between tastes and lithium chloride

Wistar rats learned to withhold consumption of a target solution when morphine preceded presentation of the target solution and lithium chloride (LiCl) and to consume the same target solution when saline preceded the presentation of the solution. After this serial feature discrimination training, morphine did not block the formation of a Pavlovian association between saccharin and LiCl but did suppress consumption of familiar tap water. After Pavlovian conditioning, morphine blocked the formation of an association between saccharin and LiCl but did not suppress consumption of a familiar tap water solution. The roles of morphine and saline can be interchanged. It appears that the morphine discriminative stimulus is calling up a representation of neither the conditioned stimulus nor the unconditional stimulus alone, but rather a modified representation of some aspect of their association.     

Typicality effects in artificial categories: is there a hemisphere difference?

In category classification tasks, typicality effects are usually found: accuracy and reaction time depend upon distance from a prototype. In this study, subjects learned either verbal or nonverbal dot pattern categories, followed by a lateralized classification task. Comparable typicality effects were found in both reaction time and accuracy across visual fields for both verbal and nonverbal categories. Both hemispheres appeared to use a similarity-to-prototype matching strategy in classification. This indicates that merely having a verbal label does not differentiate classification in the two hemispheres.     

How to study the kinetic depth effect experimentally

Sperling, Landy, Dosher, and Perkins (1989) proposed an objective 3D shape identification task with 2D artifactual cues removed and with full feedback (FB) to the subjects to measure KDE and to circumvent algorithmically equivalent KDE-alternative computations and artifactual non-KDE processing. (1) The 2D velocity flow-field was necessary and sufficient for true KDE. (2) Only the first-order (Fourier-based) perceptual motion system could solve our task because the second-order (rectifying) system could not simultaneously process more than two locations. (3) To ensure first-order motion processing, KDE tasks must require simultaneous processing at more than two locations. (4) Practice with FB is essential to measure ultimate capacity (aptitude) and, thereby, to enable comparisons with ideal observers. Experiments without FB measure ecological achievement--the ability of subjects to extrapolate their past experience to the current stimuli.     

Are FACES-II ‘family satisfaction’ scores valid?

It has been suggested that family satisfaction can be measured by having a person complete the Family Adaptability and Cohesion Evaluation Scale (FACES-II) twice: once as the person essentially sees the family (actual version), and once as they wish the family to be (ideal version). The discrepancy between the actual and ideal scores is contended to be a measure of satisfaction with family. Though conceptually attractive, this measurement strategy was not verified, as assessed in the present study by correlating the actual-ideal discrepancy scores with family discord (Index of Family Relations) scores. Clinical adoption of the actual-ideal discrepancy-score as a measure of family satisfaction is thus seen as premature, until more supportive evidence is demonstrated.     

Efficacy of behavioral management and patient education on vascular access cleansing compliance in hemodialysis patients

Compared four treatment conditions to test their ability to enhance compliance with vascular access cleansing (VAC) procedures in a group of 56 hemodialysis patients. The conditions were patient education, behavioral management with monetary incentive, patient education/behavioral management, and attention control. Behavioral observers rated VAC behavior at pretreatment, posttreatment 1-month follow-up, and 1-year follow-up. Knowledge of VAC procedures was also assessed via a questionnaire at pretreatment and posttreatment. Data were analyzed using repeated-measures multivariate analyses of variance. Results indicated that the patients in the education/behavioral, behavioral, and education groups gave significantly more correct answers on our VAC knowledge questionnaires at posttreatment than did patients in the attention control group. Further, patients in the education/behavioral and behavioral groups completed significantly more VAC steps at posttreatment and 1-month follow-up than did patients in the education group and in the attention control group. Differences were not maintained at 1-year follow-up, although more than 50% of the patients were lost to follow-up. Implications of the present findings for behavioral and educational interventions are discussed.