Differential acquisition of lever pressing in inbred and outbred mice: comparison of one-lever and two-lever procedures and correlation with differences in locomotor activity

Recent progress in mouse genetics has led to an increased interest in developing procedures for assessing mouse behavior, but relatively few of the behavioral procedures developed involve positively reinforced operant behavior. When operant methods are used, nose poking, not lever pressing, is the target response. In the current study differential acquisition of milk-reinforced lever pressing was observed in five inbred strains (C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ, and BALB/cJ) and one outbred stock (CD-1) of mice. Regardless of whether one or two levers (an "operative" and "inoperative" lever) were in the operant chamber, a concomitant variable-time fixed-ratio schedule of milk reinforcement established lever pressing in the majority of mice within two 120-min sessions. Substantial differences in lever pressing were observed across mice and between procedures. Adding an inoperative lever retarded acquisition in C57BL/6J, DBA/2J, 129X1/SvJ, and C3H/HeJ mice, but not in CD-1 and BALB/cJ mice. Locomotor activity was positively correlated with number of lever presses in both procedures. Analyses of durations of the subcomponents (e.g., time to move from hopper to lever) of operant behavior revealed further differences among the six types of mice. Together, the data suggest that appetitively reinforced lever pressing can be acquired rapidly in mice and that a combination of procedural, behavioral, and genetic variables contributes to this acquisition.     

Changes in the neuropsychological correlates of clinical dimensions between the acute and stable phase of schizophrenia

This study was designed to investigate whether the neuropsychological correlates of the symptom dimensions of schizophrenia vary with the clinical state in patients followed from the acute to stable the phase of the illness. Fifteen patients were assessed for symptoms (SAPS-SANS) and undergone a complete neuropsychological assessment at two sessions. The first session (S1) was carried out within six days after admission, i.e., acute phase and the second (S2) at least two month after hospitalization, i.e., stable phase. The data were analyzed using stepwise regression models in which neuropsychological scores were in entered to predict each dimensional score. This analysis was applied on the S1 and S2 data as well as on the S2-S1 difference to assess the neuropsychological predictors of clinical changes. Generally, the results replicate the previous associations between neuropsychological and dimensional measures found in stable patients. In addition, this study shows if each dimension appears to rely on a key structure, symptom variations seems to involve changes in the spread of the dysfunction and/or changes in the connectivity between the key and other regions. The results also suggest that functional changes related to some symptoms dimensions occur to compensate for the dysfunction associated with other symptoms.     

Semantic processing of words, cognitive resources and N400: an event-related potentials study

The specificity of the right hemisphere (RH) contribution to the semantic processing of words is still debated. Indeed, the semantic impairments of right hemisphere damaged (RHD) subjects may be the expression of limited general cognitive resources rather than a specific impairment of semantic processing ([Monetta et al., 2001]; [Murray, 2000]). The purpose of this study was to evaluate the possibility that the N400 reflect the availability of cognitive resources through an analysis of its different amplitudes according to different semantic complexity level. Ten young adults without any history of neurological damage participated in a semantic categorization task with two different levels of difficulty based on prototypicality. Event related potential (ERP) signals from 64 electrodes were recorded. An N400 was observed during the processing of difficult words and distractors. The results show that the greatest N400 activation was observed during the processing of difficult words, thus reflecting a possible increase in the amount of required cognitive resources.     

Awe as a Scientific Emotion

Awe has traditionally been considered a religious or spiritual emotion, yet scientists often report that awe motivates them to answer questions about the natural world, and to do so in naturalistic terms. Indeed, awe may be closely related to scientific discovery and theoretical advance. Awe is typically triggered by something vast (either literally or metaphorically) and initiates processes of accommodation, in which existing mental schemas are revised to make sense of the awe‐inspiring stimuli. This process of accommodation is essential for the kind of belief revision that characterizes scientific reasoning and theory change. Across six studies, we find that the tendency to experience awe is positively associated with scientific thinking, and that this association is not shared by other positive emotions. Specifically, we show that the disposition to experience awe predicts a more accurate understanding of how science works, rejection of creationism, and rejection of unwarranted teleological explanations more broadly.     

The role of emotions for moral judgments depends on the type of emotion and moral scenario

Emotions seem to play a critical role in moral judgment. However, the way in which emotions exert their influence on moral judgments is still poorly understood. This study proposes a novel theoretical approach suggesting that emotions influence moral judgments based on their motivational dimension. We tested the effects of two types of induced emotions with equal valence but with different motivational implications (anger and disgust), and four types of moral scenarios (disgust-related, impersonal, personal, and beliefs) on moral judgments. We hypothesized and found that approach motivation associated with anger would make moral judgments more permissible, while disgust, associated with withdrawal motivation, would make them less permissible. Moreover, these effects varied as a function of the type of scenario: the induced emotions only affected moral judgments concerning impersonal and personal scenarios, while we observed no effects for the other scenarios. These findings suggest that emotions can play an important role in moral judgment, but that their specific effects depend upon the type of emotion induced. Furthermore, induced emotion effects were more prevalent for moral decisions in personal and impersonal scenarios, possibly because these require the performance of an action rather than making an abstract judgment. We conclude that the effects of induced emotions on moral judgments can be predicted by taking their motivational dimension into account. This finding has important implications for moral psychology, as it points toward a previously overlooked mechanism linking emotions to moral judgments.     

Group CBT for early psychosis--are there still benefits one year later?

Our team recently conducted a randomized controlled trial comparing group cognitive behavior therapy for psychosis (CBTp) to group social skills training for symptom management and a wait-list control group, for early psychosis. The results at post-therapy and six months provided considerable empirical support for the efficacy of the group CBTp. The results of the one-year follow-up are described here. Given the high attrition rates, mostly in the comparison and control conditions, imputations were not possible, so that only the results of those having completed more than 50% of the group CBTp are presented. Significant improvements at 12 months were found for social support and insight. Negative symptoms remained low, whereas positive symptoms went back to pre-therapy levels. Challenges regarding attrition with this clientele are discussed.     

What Does the Alliance Predict in Group Interventions for Early Psychosis?

The therapeutic alliance is considered an essential component of any clinical or psychological intervention. The therapeutic alliance can however change over time, and therefore it is relevant to determine if the alliance and its variations are related to clinical outcomes. The present study had three objectives: (1) determine the impact of the alliance measured by the client and the therapist, on clinical and psychosocial outcomes of individuals with early psychosis receiving group interventions; (2) measure the concordance between the client and the therapists’ ratings of the alliance; and (3) determine the best predictor of the client’s alliance in our sample. A total of 36 individuals with early psychosis who participated in group interventions for symptom management answered the WAI three times, and so did the group therapists. Outcomes included measures of insight, symptoms (total, positive and negative), and self-esteem. Attendance and group participation were also measured. Results suggest that the overall client’s alliance predicted total symptoms and self-esteem at post-therapy, whereas both clients’ and therapists’ ratings predicted group attendance and participation. Greater variations in the alliance overtime for the clients were somewhat linked to worse negative symptoms at post-therapy. Alliance ratings were generally high and fairly concordant between therapists and clients. Only the baseline measure of capacity for attachment, predicted the client’s overall alliance scores. Clinical implications are discussed.     

Sexual behavior in Spanish adolescents of divorced parents

Marital breakup has been associated with numerous behavioral problems in children, such as sexual risk behaviors. This research is the first to examine sexual behaviors of Spanish adolescents related to whether their parents were married or divorced. Participants were 342 boys and girls aged between 14 and 18 years. The sample provided confidential information about their sexual behavior and birth control methods. Significant differences were only found in percentages of adolescents who had engaged in mutual masturbation, intercourse, or oral sex, and who had practiced these sexual relations in the last six months, in both cases, they were higher when the parents had broken their marital relationship. Regarding adolescents of divorced parents, engaging in intercourse is more likely in older teenagers who live with a stepparent. Moreover, older adolescents who were younger when parents divorced and who live in a reconstituted family, have more sexual partners. These and other findings are discussed.     

Handedness shapes children's abstract concepts

Can children’s handedness influence how they represent abstract concepts like kindness and intelligence? Here we show that from an early age, right‐handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left‐handers. In one experiment, children indicated where on a diagram a preferred toy and a dispreferred toy should go. Right‐handers tended to assign the preferred toy to a box on the right and the dispreferred toy to a box on the left. Left‐handers showed the opposite pattern. In a second experiment, children judged which of two cartoon animals looked smarter (or dumber) or nicer (or meaner). Right‐handers attributed more positive qualities to animals on the right, but left‐handers to animals on the left. These contrasting associations between space and valence cannot be explained by exposure to language or cultural conventions, which consistently link right with good. Rather, right‐ and left‐handers implicitly associated positive valence more strongly with the side of space on which they can act more fluently with their dominant hands. Results support the body‐specificity hypothesis ( Casasanto, 2009 ), showing that children with different kinds of bodies think differently in corresponding ways.