Dynamic effects of food magnitude on interim-terminal interaction

We tested the assumption of a facilitatory relation between periodic food presentation and schedule-induced drinking by examination of (a) elicited drinking, (b) drinking in anticipation of food delivery, and (c) possible indirect effects of food delivery on drinking. We exposed rats to a fixed-time 60-second schedule in which interfood intervals ended in either one or four food pellets with equal probability. In Phases 1 and 3, a stimulus signaled the magnitude of upcoming food presentation. In Phase 2, the stimulus was eliminated. Changes in drinking and “head-in-feeder” distributions within interfood intervals demonstrated that head-in-feeder was controlled directly by food presentation, but drinking was not. Head-in-feeder increased and drinking was reduced when large meals began or ended an interval. In Phases 4 to 6, meal size was manipulated across sessions yielding a positive relation between meal size and schedule-induced drinking. We conclude: (1) Schedule-induced drinking is determined by distributions of food-related behavior and results from indirect effects of food delivery; and (2) the amount of schedule-induced drinking and the form of the drinking distributions in this experiment can be accurately explained by two assumptions: (a) Food presentation facilitates food-related behavior through elicitation and anticipation; and (b) food-related behavior and drinking are reciprocally, linearly related.     

Validation of the sensation scale,a measure of subjective physiological responses to alcohol

The Sensation Scale was originally constructed to measure the subjective experience of physiological changes following alcohol consumption. Reduction of the original scale of 31 variables on the basis of face validity resulted in six ‘factors’ comprising 26 variables and one ‘other’ factor. These sortings are shown to have good interrater reliability. Furthermore, evidence is presented from two experiments that five of the six factors discriminated between nonalcoholic male subjects who drank either a beverage containing a moderate dose of alcohol or a nonalcoholic beverage.     

Constraints on Pavlovian aversive conditioning: Implications for avoidance learning in the rat

Four experiments investigated the relative degree of control exerted by several conditional stimuli when each stimulus: (a) preceded shock, (b) followed shock, and preceded a shock-free interval, (c) was independent of shock, or (d) was novel. When the onset of an auditory stimulus had preceded shock (Experiments 1, 2A, and 3), it always exerted conditioned excitatory control. When the same stimulus preceded a shock-free interval, it never exerted conditioned inhibitory control. When the onset of light (Experiments 2B, 4), silence (2C), or darkness (1, 2D) preceded a shock-free interval, it always exerted conditioned inhibitory control. However, when one of the latter stimuli preceded shock, it failed to exert excitatory control. Several models of this phenomenon were tested. The implications of these results for the species-specific defence reaction and two-factor theory accounts of avoidance learning were outlined.     

SCHEDULE-INDUCED DRINKING: ELICITATION,ANTICIPATION, OR BEHAVIORAL INTERACTION?

We carried out five experiments with rats on fixed-time schedules in order to define the relation between drinking and individual food-pellet presentations. In Experiment 1, unsignaled extra food occurred at the end of occasional fixed intervals, and we compared subsequent drinking patterns with drinking before the extra food presentation. In Experiment 2 we presented signaled and unsignaled extra food and measured elicited and anticipatory drinking patterns. In Experiment 3, we observed the persistence of modified drinking patterns when several consecutive intervals ended with extra pellets. In Experiments 4 and 5, we varied the magnitude of food delivery across (rather than within) sessions to replicate published findings. Results show that schedule-induced drinking is neither elicited by food presentations nor induced by stimuli associated with a high food rate. All subjects seemed to follow a simple rule: during any stimulus signaling an increase in the local probability of food delivery within a session, engage in food-related behavior to the exclusion of drinking. Schedule-induced drinking appears to be the result of dynamic interactions among food-related behavior, drinking, and other motivated behavior, rather than a direct effect of the contingencies of food reinforcement.     

The impact of sex,achievement domain,and conceptual orientation on causal attributions

Sex differences in achievement domain and achievement orientation were examined to better understand women's achievement. College students (84 women, 59 men) were asked to write brief accounts of a past success and a past failure and to provide causal attributions for each. More women recalled affiliative-process events, and proportionally more men recalled mastery-impact events. The relationship of topic domain and conceptual orientation to causal attributions was apparent only for accounts of failure. Topic domain and conceptual orientation interacted with sex to further influence stability attributions. When women conceptualized failure as a process, they emphasized attributions to effort and luck, while men accounted for the process failure by ability and task. When the failure was conceptualized in terms of final impact, the sex pattern of attributions was reversed.     

Luminous calibration of oscilloscopic displays

Procedures are described for adjusting the intensity of computer-driven oscilloscopic displays. The adjustment maintains a fixed intensity level on different occasions and equates the brightness of brief stimuli displayed for different durations (i.e., compensates for the effects of time-intensity reciprocity).     

A systematic evaluation of preferences identified through person-centered planning for people with profound multiple disabilities

Person-centered planning is becoming a popular means of designing supports for people with disabilities. However, very little research evaluating person-centered planning exists. We evaluated the degree to which items and activities reported to be preferred in person-centered plans represented accurate preferences based on how individuals responded when presented with the items and activities. Person-centered planning meetings were conducted with 4 individuals with profound multiple disabilities to develop preference maps and to identify leisure-related preferences. A sample of the reported preferences in the plans was then systematically assessed by observing each participant's approach and avoidance responses to the items and activities. Of the sampled items and activities reported to be preferred in the plans, 42% represented moderate preferences based on the latter assessment process and 33% represented strong preferences. With 2 participants, several preferences identified in the plans were nonpreferred items and activities based on the preference assessments, and some were frequently avoided. These results suggested that although person-centered plans may identify some accurate preferences for people with profound multiple disabilities, this approach should be used cautiously. Results also suggested that such plans should be supplemented with systematic preference assessments to ensure the accuracy of identified preferences. Future research areas focus on evaluating other aspects of person-centered planning.     

Description and Immediate Impacts of a Preventive Intervention for Conduct Problems

A population-based randomized intervention trial for the prevention of conduct problems (i.e., oppositional defiant disorder and conduct disorder) is described. The LIFT (Linking the Interests of Families and Teachers) intervention was designed for all first- and fifth-grade elementary school boys and girls and their families living in at-risk neighborhoods characterized by high rates of juvenile delinquency. The 10-week intervention strategy was carefully targeted at proximal and malleable antecedents in three social domains that were identified by a developmental model of conduct problems. From 12 elementary schools, 671 first and fifth graders and their families participated either in the theory-based universal preventive intervention or in a control condition. The intervention consisted of parent training, a classroom-based social skills program, a playground behavioral program, and systematic communication between teachers and parents. A multiple measure assessment strategy was used to evaluate participant satisfaction and participation, fidelity of implementation, and the immediate impacts of the program on targeted antecedents.     

Clinical cutoffs for the beck Depression inventory and the Geriatric Depression scale with older adult psychiatric outpatients

The present study developed new clinical cutoffs for the Beck Depression Inventory (BDI) and the Geriatric Depression Scale (GDS) with 59 older adult psychiatric outpatients. Maximum discrimination of a current major depressive episode resulted, with cutoff scores of 22 for the BDI and 16 for the GDS. Specifically, the following validity scores emerged for the BDI: sensitivity, 64%; specificity, 73%; positive predictive power, 75%; negative predictive power, 61%; and hit rate 68%. For the GDS the validity scores were as follows: sensitivity, 79%; specificity, 69%; positive predictive power, 77%; negative predictive power, 72%; and hit rate, 75%. Combined BDI and GDS scores did not result in improved prediction of a current major depressive episode as compared to the GDS alone. These results support the notion that the BDI and GDS are valid quick screening instruments in discriminating a current major depressive episode for older adult psychiatric outpatients.