Detection of a Cry for Help on the MMPI-2: an analog investigation

We compared Minnesota Multiphasic Personality Inventory (MMPI-2) results from 2 groups of mildly to moderately disturbed psychiatric outpatients (N=60) answering under either Standard or Cry for Help instructions. Results from previously completed intake MMPI-2 protocols were obtained for each participant. The two groups were comparable on intake MMPI-2 variables and demographic characteristics. Analysis of feedback data from the second, experimental observation indicated that the two groups had equivalent self-estimates of understanding of their role and success in simulating their role. Significant differences were found between the two groups on their experimental MMPI-2 protocols. The Cry for Help group had significantly higher scores on F, F-K, Fb, Ds2, and Fp scales as well as significantly lower scorns on the K scale. The Cry for Help group also had significantly higher scores on all clinical scales with the exception of 5, which was not tested. Cutting scores derived by Rogers, Sewell, and Ustad (1995) for the detection of a Cry for Help in outpatients were cross-validated with fairly positive results. Although these results are promising, particularly in light of the shrinkage expected on cross-validation, further research is needed in this area.     

Detecting a nonevent: Delayed presence-versus-absence discrimination in pigeons

Eight pigeons were trained on a delayed presence-versus-absence discrimination paradigm in which a sample stimulus was presented on some trials but not on others. If a sample was presented, then a response to one choice key produced food. If no sample was presented, a response to the other choice key produced food. The basic finding was that performance remained constant and well above 50% correct on no-sample trials as the retention interval increased, whereas performance dropped precipitously (to below 50% correct) on sample trials. In the second phase of the experiment, all of the trials were no-sample trials, and reinforcers were delivered probabilistically for one group of pigeons and according to time-based schedules for the other group. The exact reinforcement probabilities used in Phase 2 were those calculated to be in effect on no-sample trials in Phase 1 (according to a discrete-state model of performance). Subjects did not show exclusive preference for the richer alternative on no-sample trials in the first phase, but those in the probabilistic group developed near-exclusive preference for the richer alternative during the second phase. These data are inconsistent with the predictions of the discrete-state model, but are easily accommodated by an account based on signal detection theory, which also can be applied effectively to discrimination of event duration and the “subjective shortening” effect.     

Substitution and caloric regulation in a closed economy.

Three experiments were conducted to study the effect of an imperfect substitute for food on demand for food in a closed economy. In Experiments 1 and 2, rats pressed a lever for their entire daily food ration, and a fixed ratio of presses was required for each food pellet. In both experiments, the fixed ratio was held constant during a daily session but was increased between sessions. The fixed ratio was increased over a series of daily sessions once in the absence of concurrently available sucrose and again when sucrose pellets were freely available. For both series, increases in the fixed ratio reduced food intake, but body weight was reduced only in the no-sucrose condition. In the sucrose condition, body weight and total caloric intake (sucrose plus food) were relatively unaffected by increases in the fixed ratio. At all fixed ratios, food intake was proportionally reduced by the intake of sucrose. In Experiment 3, monkeys obtained food or saccharin by pressing keys; the fixed ratio of presses per food pellet was increased once when tap water was each monkey's only source of fluid, again when each monkey's water was sweetened with saccharin, and a third time when each monkey had concurrent access to the saccharin solution and plain water. Increases in the fixed ratio, but not the intake of the saccharin solution, reduced each monkey's food intake. Because neither rats' sucrose nor monkeys' saccharin intakes affected the slope of the respective demand curves for food, monkeys and rats increased their daily output of presses and thereby defended their daily intake of those complementary elements of food. However, sucrose reduced rats' food intake. The relative constancy of body weight and total caloric intake in the sucrose condition is consistent with the possibility that rats tended to regulate caloric intake.     

ELECTROCORTICAL DIFFERENTIATION OF EVALUATIVE AND NONEVALUATIVE CATEGORIZATIONS

Abstract— The evaluative categorizations that underlie affective and attitudinal judgments have often been equated with non-evaluative categorizations despite the central importance of evaluative processes for survival In the present experiment, a late positive potential (LPP) of the event-related brain potential elicited when participants evaluatively categorized food items as positive or nonpositive was compared with the LPP elicited when participants semantically (i e., nonevaluatively) categorized food items as vegetable or nonvegetable Results revealed that evaluative categorizations evoked an LPP that was relatively larger over the right than the left scalp regions compared with the LPP evoked by nonevaluative categorizations. This finding provides evidence regarding the differences in neural and cognitive processes involved in evaluative and nonevaluative categorizations.     

Problem–Problem Solver Characteristics Affectingthe Calibration of Judgments

The purpose of this paper is to examine factors that affect the calibration of judgments by systematically comparing experts’ judgments to novices’ when solving a complex, real-world problem that varies in its initial characteristics. Calibration in this context refers to the proportion of times decision makers provide a range about their best estimates that includes the actual outcome. We found that experts specify a narrower range and provide more accurate best estimates than novices. But their tighter ranges are not justified by their greater accuracy: they are less likely to encompass the actual outcome than are novices. However, this effect is attenuated when solving more complex problems. Novices apparently underestimate the complexity of difficult problems, hence the accuracy of their best estimates decreases as does the width of their ranges, resulting in worse calibration. The performance of experts was not significantly different across problem solving conditions. Both groups provided asymmetrical ranges about their best estimates, which suggests they account for the effect of subproblem dependencies.     

Control of fixation duration in a simple search task

To obtain insight into the control of fixation duration during visual search, we had 4 subjects perform simple search tasks in which we systematically varied the discriminability of the target. The experiment was carried out under two conditions. Under the first condition (blocked), the discriminability of the target was kept constant during a session. Under the second condition (mixed), the discriminability of the target varied per trial. Under the blocked condition, fixation duration increased with decreasing discriminability. For 2 subjects, we found much shorter fixation durations in difficult trials with the mixed condition than in difficult trials with the blocked condition. Overall, the subjects fixated the target, continued to search, and then went back to the target in 5%–55% of the correct trials. In these trials, the result of the analysis of the foveal target was not used for preparing the next saccade. The results support a preprogramming model of the control of fixation duration. In a simple search task, control of fixation duration appears to be indirect.     

Psychosocial characteristics of preschool siblings of handicapped and nonhandicapped children

This project examined psychosocial characteristics of 24 preschool-aged siblings of handicapped children in relation to a control group of 22 siblings of nonhandicapped children. Subjects were matched on family size and income, sibling age, birth order, sex, age spacing, and marital status of their parents. Results indicated no statistically significant differences between groups of children on measures of perceived self-competence and acceptance, understanding of developmental disabilities, empathy, and child care responsibility. Significant group differences were found where brothers of handicapped children were rated by their mothers as being more depressed and aggressive than brothers of nonhandicapped control children. Sisters of handicapped children were rated by mothers as being more aggressive than sisters of nonhandicapped children. Sisters of handicapped children and brothers of nonhandicapped children had significantly fewer privileges and more restrictions on their home activities than other groups. Results are discussed in relation to previous research on older silbings of handicapped children and the general literature on family stress and childhood disability and disease. The importance of examining sibling functioning via multiple measures of child behavior is stressed.The authors are grateful to the children and families who participated in the project. The assistance of Dr. Ricardo Barrera, Christine DiBlasio, Lisa Kaye, Paola Bellabarba, Jeanne Logozzo, Donna Motley, Jennifer Harter, and Tina Meisell is also gratefully acknowleged. This project was funded by Grant Number G008300345 from the U.S. Department of Education.     

Feasibility and effectiveness of school-based relaxation in lowering blood pressure

Progressive muscle relaxation (PMR) is a broadly useful anxiety reduction technique that has been found to lower blood pressure (BP) in essential hypertension. The present investigation is the first to evaluate the feasibility and efficacy of wide-scale PMR instruction as a public health promotion strategy aimed at adolescents. Students (N = 1,400) in Grades 9 and 10 at two large Baltimore City public high schools underwent BP screening; those with BP persistently above the 85th percentile were randomly assigned to (a) 12 weeks daily PMR instruction provided in class for academic credit or (b) a control condition. The latter students had their BP measured at the same frequency as the PMR students and completed the PMR course during the following year. Approximately two thirds of eligible students entered and completed the study. Results demonstrated that treatment students (n = 51) enjoyed daily PMR, mastered the technique, and achieved reduced systolic BP at posttest relative to the untrained controls (n = 59). At follow-up 4 months later, group BP differences were not significant. Implications for use of PMR to promote cardiovascular health are discussed.