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.     

Imagery intervention in open and closed tennis motor skill performance

To assess use of imagery intervention in performance of two tennis motor skills the quasi-experimental design included a pre- and posttest and a control group. The tennis service shot and service receiving skill were selected as representative of open and closed skills, respectively. 48 subjects, male tennis players, whose ages ranged from 16 to 18 yr. (M = 17.2), were divided into two groups: (1) Technical practice only which was used as control group and (2) Imagery group who received both imagery and technical practice. Analysis of covariance showed a significant main effect for the imagery intervention on the closed skill (p = .002). Findings suggest that imaging a positive outcome may be more powerful in improving performance of closed skill movements than of open skill movements.     

Changing Patterns of Gender Portrayals in Portuguese Television Advertisements1

The purpose of this study was to identify patterns in Portuguese television advertisements and interpret changes in the portrayal of gender roles using data collected 7 years apart: 1996 and 2003. We grouped 11 attributes of the central figure displayed in 623 evening commercials using a k‐means cluster procedure. There were 4 distinct groups of advertisements that emerged, 2 of them characterizing a predominantly male central figure and the other 2 a female central figure. The overall increase in women portrayed in advertisements from 1996 (32.9%) to 2003 (40.8%) is reflected in a shift toward an increase of advertisements with a female central figure in the typically male “narrator” cluster. Practical implications of these findings are discussed.