Pre-training anandamide infusion within the basolateral amygdala impairs plus-maze discriminative avoidance task in rats

Endocannabinoids (eCBs) modulate a variety of brain functions via activation of the widely expressed CB1 receptor. One site of high density of this receptor is the basolateral amygdala (BLA), a structure involved in the formation of aversive memories. The activation and blockade of CB1 receptors by systemic or hippocampal drug administrations have been shown to modify memory processing. However, little is known about the role of the BLA endocannabinoid system in aversive memories. Additionally, BLA endocannabinoid transmission seems to be related to emotional states, but the relevance of these effects to memory formation is still unknown. In this study we investigated the effects of the eCB anandamide (AEA) and the CB1 antagonist/inverse agonist AM251 infused into the BLA on the acquisition of an aversive memory task, concomitantly evaluating basal anxiety levels in rats. Male rats received pre-training micro-injection of AEA, AM251 or vehicle bilaterally into the BLA, and were studied with the plus-maze discriminative avoidance task (a paradigm that allows concomitant and independent evaluation of anxiety-like behavior and the memory of an aversive task). Our results showed that AEA into the BLA before training prevented memory retrieval 24 h later, as evaluated by exploration of the aversive arm of the maze, while AM251 into the BLA did not interfere with animals' performance. In addition, AEA had no effect on anxiety-like behavior (as evaluated by open arm exploration and risk assessment), while AM251 induced an anxiogenic effect. Our data indicate an important role of BLA CB1 receptors in aversive memory formation, and suggest that this involvement is not necessarily related to a possible modulation of anxiety states.     

Competence to be executed: An ethical analysis post Panetti

Competence to be executed evaluations in effect can prevent an execution or remove the last meaningful impediment to it. Forensic psychiatrists have primary duties to the legal system and truth and honesty, but like all other areas of medical consultation also should balance conflicting secondary traditional medical ethical duties. Participation in a legally authorized execution so violates medical roles, that it is ethically prohibited by the American Medical Association and American Psychiatric Association. This prohibition includes treatment intended to restore competence to be executed. However, despite the primary treatment intent otherwise being appropriate ethically, like relieving suffering or fostering prison safety, if competence to be executed almost predictably would be a treatment result, at least the risk of this result should be considered ethically as if it were intended. In contrast, competence to be executed assessments can be ethical. Diamond's approach of performing honest evaluations only for the defense is an ethical option for such assessments. However, it is challenging to persuade judges and juries of the objectivity of such honest legitimate assessments. Most practitioners therefore likely would consider assessing competence to be executed for either side. This ethically hazardous position necessitates sensitivity to potentially seriously conflicting duties and roles. Copyright © 2010 John Wiley & Sons, Ltd.     

Factor structure and behavioural correlates of the Psychopathy Checklist-Revised [PCL-R] in a Brazilian prisoner sample

The present study examines the reliability, factor structure, and criterion-related validity of Hare (2003) Revised Psychopathy Checklist [PCL-R] in a Latin American forensic context. Brazilian male inmates (124) were administered the PCL-R, along with relevant subscales of an inventory of normal personality [Personality Factorial Inventory], an intelligence scale [Standard Progressive Matrices], and a semi-structured interview based in DSM IV. Criminal offence records were obtained from prison files. Several theoretical factorial structures for the PCL-R were tested and compared. A bifactor model with three factors, one general factor reflecting the overlap across all items, and two independent subfactors reflecting the unique covariation among particular groups of items, shows the better fit. Overall scores on the PCL-R correlated with the number of criminal offenses committed by participants. No significant correlations were found between PCL-R scores and personality or intelligence measures. It was concluded that the PCL-R is a reliable and valid instrument for the assessment of psychopathy in the Brazilian male forensic population.     

Autophosphorylation of alphaCaMKII is differentially involved in new learning and unlearning mechanisms of memory extinction

Accumulating evidence indicates the key role of alpha-calcium/calmodulin-dependent protein kinase II (alphaCaMKII) in synaptic plasticity and learning, but it remains unclear how this kinase participates in the processing of memory extinction. Here, we investigated the mechanism by which alphaCaMKII may mediate extinction by using heterozygous knock-in mice with a targeted T286A mutation that prevents the autophosphorylation of this kinase (alphaCaMKII(T286A+/-)). Remarkably, partial reduction of alphaCaMKII function due to the T286A(+/-) mutation prevented the development of extinction without interfering with initial hippocampus-dependent memory formation as assessed by contextual fear conditioning and the Morris water maze. It is hypothesized that the mechanism of extinction may differ depending on the interval at which extinction training is started, being more akin to "new learning" at longer intervals and "unlearning" or "erasure" at shorter intervals. Consistent with this hypothesis, we found that extinction conducted 24 h, but not 15 min, after contextual fear training showed spontaneous recovery (reappearance of extinguished freezing responses) 21 d following the extinction, representing behavioral evidence for new learning and unlearning mechanisms underlying extinction 24 h and 15 min post-training, respectively. Importantly, the alphaCaMKII(T286A+/-) mutation blocked new learning of contextual fear memory extinction, whereas it did not interfere with unlearning processes. Our results demonstrate a genetic dissociation of new learning and unlearning mechanisms of extinction, and suggest that alphaCaMKII is responsible for extinguishing memories specifically through new learning mechanisms.     

CONCURRENT RESURGENCE AND BEHAVIORAL HISTORY

The contribution of past experiences to concurrent resurgence was investigated in three experiments. In Experiment 1, resurgence was related to the length of reinforcement history as well as the reinforcement schedule that previously maintained responding. Specifically, more resurgence occurred when key pecks had been reinforced on a variable-interval 1-min schedule than a variable-interval 6-min schedule, but this effect may have been due either to the differential reinforcement rates or differential response rates under the two schedules. When reinforcement rates were similar (Experiment 2), there was more resurgence of high-rate than low-rate responding. When response rates were similar (Experiment 3), resurgence was not related systematically to prior reinforcement rates. Taken together, these three experimental tests of concurrent resurgence illustrate that prior response rates are better predictors of resurgence than are prior reinforcement rates.     

The Quality of Home Environment in Brazil: An Ecological Model

Based on Bronfenbrenner's (1999) ecological perspective, a longitudinal, prospective model of individual differences in the quality of home environment (Home Observation for Measurement of the Environment—HOME) was tested in a sample of 179 Brazilian children and their families. Perinatal measures of family socioeconomic status (SES) and child birth weight had direct effects on HOME at preschool age. As either family SES or child birth weight increased, HOME also increased through diminished emotional distress in the mother a month following childbirth. SES had a negative effect on number of children in the household, which in turn had a long-term negative impact on HOME. Compared to mothers who had reported not to plan their pregnancy, those who did were more likely to have fewer children, to report more spouse support during childbearing, and to show less emotional distress a month after childbirth, all of which also influenced HOME at preschool age. These findings are discussed in light of the broader socio-ecological Brazilian context, with direct implications to clinical practice aimed at improving the quality of home environment.     

Validation of a Portuguese version of the multidimensional measure of employability

This study describes the validity and reliability evidence of the multidimensional measure of employability (MME) based on the internal structure and relations to career self-efficacy and career success. Two hundred forty seven Portuguese persons (75.7% women) aged from 21–73 years old (M = 39.9, SD = 10.9) participated. Confirmatory factor analysis suggested adequate fit in the correlational and hierarchical models. Measurement reliability was good for total score and each factor. Correlations with the additional measures provided evidence of validity. MME provides a tool for research and career counseling, enabling comprehensive employability assessment and personalized interventions, while recognising the interplay between employability dimensions.     

Social cognitive predictors of well-being in African college students

Lent and Brown's (2006, 2008) social cognitive model of work well-being was tested in two samples of African college students, one from Angola (N = 241) and one from Mozambique (N = 425). Participants completed domain-specific measures of academic self-efficacy, environmental support, goal progress, and satisfaction, along with measures of global positive affect and life satisfaction. Path analyses indicated that the model fit the data well overall, both in the full sample and in separate sub-samples by country and gender. Contrary to expectations, however, self-efficacy predicted academic satisfaction only indirectly, via goal progress; and goal progress predicted life satisfaction only indirectly, via academic satisfaction. The predictors accounted for substantial portions of the variance in both academic domain satisfaction and life satisfaction. Implications for research and practice involving the social cognitive model are considered.     

Maintained attitudinal changes in nursing personnel after a brief training on suicide prevention

Nursing personnel (N = 317) working at a general hospital attended a 6-hour training program on suicide prevention. They answered anonymously pre- and post-training the Suicide Behavior Attitude Questionnaire (SBAQ), which comprises 21 visual analogue scale items divided in three factorial subscales. The results indicated there were positive changes in the attitudes and these gains were significantly maintained at the 6-month follow-up evaluation. Improvement was in the Feelings and Professional Capacity subscales (ANOVA; p = 0.0001 and 0.01, respectively). There was no change on the Right to Suicide subscale. Because attitudes influence the effectiveness of health care personnel interventions, our findings may have important implications for the development of suicide prevention programs.     

Neural events in the reinforcement contingency

When neural events are analyzed as stimuli and responses, functional relations among them and among overt stimuli and responses can be unveiled. The integration of neuroscience and the experimental analysis of behavior is beginning to provide empirical evidence of involvement of neural events in the three-term contingency relating discriminative stimuli, responses, and consequences. This paper is aimed at highlighting exemplar instances in the development of this issue. It has long been known that the electrical stimulation of certain cerebral areas can have a reinforcing function. Extraordinary technological advances in recent years show that neural activity can be selected by consequences. For example, the activity of in vitro isolated neurons that receive dopamine as a reinforcer functions as a cellular analogue of operant conditioning. The in vivo activity of populations of neurons of rats and monkeys can be recorded on an instant-to-instant basis and can then be used to move mechanical arms or track a target as a function of consequences. Neural stimulation acts as a discriminative stimulus for operant responses that are in turn maintained by neural consequences. Together with investigations on the molecular basis of classical conditioning, those studies are examples of possibilities that are being created for the study of behavior-environment interactions within the organism. More important, they show that, as an element in the three-term contingency, neural activity follows the same laws as other events.