Towards mouse models of perseveration: a heritable component in extinction of operant behavior in fourteen standard and recombinant inbred mouse lines

Extinction of instrumental responses is an essential skill for adaptive behavior such as foraging. So far, only few studies have focused on extinction following appetitive conditioning in mice. We studied extinction of appetitive operant lever-press behavior in six standard inbred mouse strains (A/J, C3H/HeJ, C57BL/6J, DBA/2J, BALB/cByJ and NOD/Ltj) and eight recombinant inbred mouse lines. From the response rates at the end of operant and extinction training we computed an extinction index, with higher values indicating better capability to omit behavioral responding in absence of reward. This index varied highly across the mouse lines tested, and the variability was partially due to a significant heritable component of 12.6%.To further characterize the relationship between operant learning and extinction, we calculated the slope of the time course of extinction across sessions. While many strains showed a considerable capacity to omit responding when lever pressing was no longer rewarded, we found a few lines showing an abnormally high perseveration in lever press behavior, showing no decay in response scores over extinction sessions.No correlation was found between operant and extinction response scores, suggesting that appetitive operant learning and extinction learning are dissociable, a finding in line with previous studies indicating that these forms of learning are dependent on different brain areas. These data shed light on the heritable basis of extinction learning and may help develop animal models of addictive habits and other perseverative disorders, such as compulsive food seeking and eating.     

Covariance structure analysis in experimental research: Comparing two word translation models

Covariance structure analysis is a statistical technique in which a theoretical model, or a covariance structure, is constructed, and the covariances predicted by the theoretical model are compared with those of the observed data. The adequacy of the model in reproducing the sample covariances is reflected by estimates of the parameters of the model and measures indicating the goodness of fit. Covariance structure analysis is frequently used for analyzing data obtained in nonexperimental or quasiexperimental research, but is seldom employed in experimental research. In this paper, the applicability of this technique in experimental research is discussed and illustrated by covariance structure analysis studies in which two models for word translation—the symmetrical model and the asymmetrical model—are described, refined, and contrasted.     

Moral counselling: a method in development

This article describes a method of moral counselling developed in the Radboud University Medical Centre Nijmegen (The Netherlands). The authors apply insights of Paul Ricoeur to the non-directive counselling method of Carl Rogers in their work of coaching patients with moral problems in health care. The developed method was shared with other health care professionals in a training course. Experiences in the course and further practice led to further improvement of the method.     

Effects of slow-release caffeine and a nap on driving simulator performance after partial sleep deprivation

A driving simulator was used to evaluate the effectiveness of a 30-min. nap and 300-mg slow-release caffeine as countermeasures to drivers' sleepiness induced by partial sleep deprivation. 12 participants were allowed 45 hr. time in bed at the laboratory. Driving performance then was measured twice--at 9 a.m. and at 1 p.m.--by a 45-min. driving task on a simulator. Subjective sleepiness/alertness and mood were assessed four times on the Stanford Sleepiness Scale and the Profile of Mood States. Driving performance was assessed as Lane Drifting, Speed Deviation, and Accident Liability. A 30-min. nap opportunity and 300 mg of slow-release caffeine both were successful in counteracting drivers' sleepiness. The remedial effect of slow-release caffeine lasted longer than that of the nap, that is, it was also effective in the afternoon session. This suggests that slow-release caffeine represents a valuable countermeasure that, in the case of partial sleep deprivation, is preferred to a nap when sleepiness has to be counteracted for a longer time.     

Cognitive-behavioral therapy for women with lifelong vaginismus: process and prognostic factors

Cognitive-behavioral therapy (CBT) seems an effective treatment of lifelong vaginismus, but mechanisms of action have not yet been established. The present study explored whether the effect of CBT for lifelong vaginismus is mediated by changes in fear of penetration and avoidance behavior, which CBT explicitly aims to alter. A second aim of this study was to predict treatment outcome on the basis of pre-treatment variables. Participants with lifelong vaginismus were allocated at random to a 3-months CBT (n=81) or a waiting-list control condition (n=36). Full vaginal penetration with the penis of the partner constituted the primary outcome measure. Change scores in successful 'non-coital penetrative-behavior' and 'fear of coitus' were used to measure the mediating variables. Treatment resulted in an increase of intercourse (outcome), a decrease in fear of coitus, and an enhancement of successful non-coital penetration behavior, compared with no treatment. Outcome (intercourse) was partly mediated by changes in fear of coitus and changes in avoidance behavior. No treatment predictors could be detected in this study sample. It is concluded that techniques such as gradual exposure, aimed at decreasing avoidance behavior and penetration fear, constitute an important avenue of change in the treatment of lifelong vaginismus.     

An eye movement analysis system (EMAS) for the identification of cognitive processes on figural tasks

EMAS is a software system (written in VAX-11 FORTRAN) for the analysis of eye movement data recorded during the performance of figural tasks. Its main functions are: (1) Calibration of raw coordinates of eye movements to determine their actual position on the stimulus display. Different kinds of measurement distortion may be corrected. (2) Identification of eye fixations and the determination of their locations and durations. (3) Analysis of fixation sequences. The frequency of transitions of fixations among specified sectors of the stimulus display is computed. A sequential list is made of the successive fixations in which the fixated sector and the fixation duration are graphically indicated. (4) Plotting of raw or calibrated eye movement data and fixation points. The sequence of fixations in specified display sectors can also be plotted in real time. Applications of the programs to the Embedded Figures Test and the Hidden Figures Test are illustrated.     

Cross-cultural generalizability of the youth self-report and teacher's report form cross-informant syndromes

Exploratory factor analyses on 569 Youth Self-Reports and 1,221 Teacher's Report Forms of clinically referred Dutch children revealed six and eight factors respectively, very similar to the eight YSR and TRF cross-informant syndromes derived by Achenbach (1991c, 1991d). Mean cross-cultural correlations were .89 for YSR syndromes and .95 for TRF syndromes. In confirmatory factor analyses of the Dutch and American YSR and TRF factor models in cross-validation samples of 570 YSRs and 1,221 TRFs, goodness-of-fit indices were only slightly better for Dutch factor models. The American cross-informant Social Problems and Attention Problems syndromes had the poorest fit. The application of the eight American cross-informant syndromes to Dutch self-and teacher reports was supported.We wish to thank Dr. Thomas Achenbach for his comments and advice on this article.This research was supported by grants from the Sophia Foundation for Medical Research and from the Dutch National Program for Stimulation of Health Research.