Basolateral amygdala noradrenergic activity is involved in the acquisition of conditioned odor aversion in the rat

Conditioned odor aversion (COA) is the avoidance of an odorized-tasteless solution (the conditioned stimulus, CS), the ingestion of which precedes toxicosis. Previous works have shown that the basolateral nucleus of the amygdala (BLA) is involved in the acquisition, and more precisely, the control of the CS memory trace, of COA. Since catecholamine depletion of the amygdala induced a deficit in the potentiated version of COA, this study investigated the role of the adrenergic system in the BLA during COA. Male Wistar rats bilaterally implanted with cannulae aimed at the BLA were microinjected with the beta-adrenergic antagonist propranolol (1 microg/0.2 microl) during the acquisition (5 min before the CS presentation, pre-CS, or immediately after, post-CS) or during the retrieval test (5 min before test, pre-test). Results showed that pre-CS, but neither post-CS nor pre-test, infusions of propranolol impaired COA, suggesting that beta-adrenergic system activity in the BLA is involved in the acquisition but not the expression of COA. Moreover, the fact that pre-CS, but not post-CS, treatment disrupted COA suggests that beta-adrenergic system in the BLA is involved in the initiation but not the maintenance of the CS memory trace during COA acquisition.     

Working memory deficits in transgenic rats overexpressing human adenosine A2A receptors in the brain

Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients.     

Factor structure of the Perceived Stress Scale (PSS) in a sample from Mexico

The aim of this study was to analyze the cultural adaptation of the European Spanish version of the Perceived Stress Scale (PSS; Cohen, Kamarak, & Mermelstein, 1983), for its use in Mexican samples. Using a random sample of students, internal consistency was analyzed and the factor structure of the Spanish version of the PSS was compared with the factor structure found in the English version. Internal consistency was adequate (alpha = .83) and confirmatory factor analysis corroborated the factor structure. Factor 1 explained 42.8% of the variance and Factor 2 accounted for 53.2%. The goodness-of-fit measures also revealed an adequate fit. The cultural adaptation of the PSS was also evaluated with satisfactory results.     

Toward a dialect theory: cultural differences in the expression and recognition of posed facial expressions

Two studies provided direct support for a recently proposed dialect theory of communicating emotion, positing that expressive displays show cultural variations similar to linguistic dialects, thereby decreasing accurate recognition by out-group members. In Study 1, 60 participants from Quebec and Gabon posed facial expressions. Dialects, in the form of activating different muscles for the same expressions, emerged most clearly for serenity, shame, and contempt and also for anger, sadness, surprise, and happiness, but not for fear, disgust, or embarrassment. In Study 2, Quebecois and Gabonese participants judged these stimuli and stimuli standardized to erase cultural dialects. As predicted, an in-group advantage emerged for nonstandardized expressions only and most strongly for expressions with greater regional dialects, according to Study 1.     

Parental Perceptions of Characteristics of Non-Parental Child Care: Belief Dimensions, Family and Child Correlates

Investigators argue that it is essential to consider why parents select non-parental child care arrangements in studying the effects of that care on a child’s development. Existing investigations explore family economic and demographic characteristics as determinants of child care choice. The present investigation examined a wide array of parents’ beliefs about characteristics of child care arrangements with the goal of determining if these could be reduced to coherent dimensions. The emergent belief sets were examined in relation to maternal and child characteristics as potential correlates. Two hundred and twenty respondents with children in non-parental care completed surveys. These individuals represent diverse ethnic and economic groups. Ratings of the importance of characteristics were factor analyzed resulting in a six factor solution: Practical Concerns, Institutional Structure, Curriculum, Scheduling, Child Centered Orientation and School Readiness. The latter factor, or program components promoting social skills and classroom behaviors associated with succeeding in school, was identified as the most important dimension. Parents describing their children as more difficult temperamentally and as less developmentally advanced tended to describe school readiness and curriculum issues as less important. Child characteristics accounted for unique variance above and beyond mothers’ characteristics in predicting to parental beliefs. Results suggest that parents as consumers possess coherent belief sets and are sensitive to children’s developmental needs in evaluating care arrangements.     

A genetic analysis of brain volumes and IQ in children

In a population-based sample of 112 nine-year old twin pairs, we investigated the association among total brain volume, gray matter and white matter volume, intelligence as assessed by the Raven IQ test, verbal comprehension, perceptual organization and perceptual speed as assessed by the Wechsler Intelligence Scale for Children-III. Phenotypic correlations between the brain volumes and intelligence traits ranged between .20 and .33. Processing speed and brain volume did not correlate. The relation between brain volume and intelligence was entirely explained by a common set of genes influencing both sets of phenotypes.     

ERPs studies of cognitive processing during sleep

In the last few decades, several works on cognitive processing during sleep have emerged. The study of cognitive processing with event related potentials (ERPs) during sleep is a topic of great interest, since ERPs allow the study of stimulation with passive paradigms (without conscious response or behavioural response), opening multiple research possibilities during different sleep phases. We review ERPs modulated by cognitive processes during sleep: N1, Mismatch Negativity (MMN), P2, P3, N400-like, N300-N550, among others. The review shows that there are different cognitive discriminations during sleep related to the frequency, intensity, duration, saliency, novelty, proportion of appearance, meaning, and even sentential integration of stimuli. The fascinating results of cognitive processing during sleep imply serious challenges for cognitive models. The studies of ERPs, together with techniques of neuroimaging, have demonstrated the existence of cognitive processing during sleep. A fundamental question to be considered is if these cognitive phenomena are similar to processing that occurs during wakefulness. Based on this question we discussed the existence of possible mechanisms associated with sleep, as well as the specific cognitive and neurophysiologic differences of wakefulness and sleep. Much knowledge is still required to even understand the conjunction of dramatic changes in cerebral dynamics and the occurrence of cognitive processes. We propose some insights based on ERPs research for further construction of theoretical models for integrating both cognitive processing and specific brain sleep dynamics.     

Developmental dyslexia and widespread activation across the cerebellar hemispheres

Developmental dyslexia is the most common learning disability in school-aged children with an estimated incidence of five to ten percent. The cause and pathophysiological substrate of this developmental disorder is unclear. Recently, a possible involvement of the cerebellum in the pathogenesis of dyslexia has been postulated. In this study, 15 dyslexic children and 7 age-matched control subjects were investigated by means of functional neuroimaging (fMRI) using a noun-verb association paradigm. Comparison of activation patterns between dyslexic and control subjects revealed distinct and significant differences in cerebral and cerebellar activation. Control subjects showed bilaterally well-defined and focal activation patterns in the frontal and parietal lobes and the posterior regions of the cerebellar hemispheres. The dyslexic children, however, presented widespread and diffuse activations on the cerebral and cerebellar level. Cerebral activations were found in frontal, parietal, temporal and occipital regions. Activations in the cerebellum were found predominantly in the cerebellar cortex, including Crus I, Crus II, hemispheric lobule VI, VII and vermal lobules I, II, III, IV and VII. This preliminary study is the first to reveal a significant difference in cerebellar functioning between dyslexic children and controls during a semantic association task. As a result, we propose a new hypothesis regarding the pathophysiological mechanisms of developmental dyslexia. Given the sites of activation in the cerebellum in the dyslexic group, a defect of the intra-cerebellar distribution of activity is suspected, suggesting a disorder of the processing or transfer of information within the cerebellar cortex.     

Predicting romantic relationship satisfaction from life history strategy

Attachment style and communication style have been shown in previous research to predict relationship satisfaction. We hypothesized that the ultimate cause underlying the relationship among attachment style, communication style, and relationship satisfaction is Life History Strategy (LHS). Furthermore, we hypothesized that LHS would not only predict relationship satisfaction indirectly through a couple’s attachment style and communication style, but would also predict relationship satisfaction directly. Two structural equation models were constructed to model and test each of these hypotheses. The first showed that the indirect causal pathways from LHS to attachment style, attachment style to communication style, and communication style to relationship satisfaction predicted 16% of the variance in relationship satisfaction. The second added a causal pathway directly from LHS to relationship satisfaction which reduced the estimate for the influence of communication style on relationship satisfaction and increased the total variance predicted in relationship satisfaction to 60%. These results challenge the notion that it is primarily the communication between two romantic partners which influences their relationship outcome by proposing that their LHS may be influential: (1) indirectly through their attachment style and communication style; and (2) directly upon relationship satisfaction.     

Building an Expanded Therapeutic Alliance: A Task Analysis with Families Trapped in Parental-Adolescent Conflict

Parental-adolescent conflict is part of the normal developmental cycle of families, but when it occurs in a dysfunctional way, it is associated with the appearance of various harmful conditions for the family system and for the adolescent in particular. Family therapy is one of the main options for psychotherapeutic intervention in these cases and has ample evidence of its effectiveness. The success of this intervention is conditioned to the construction of an adequate therapeutic alliance with the family, but the process of this task has not been clarified yet. The present study is a task analysis, the purpose of which was to create a heuristic model of how an expanded alliance may be built in these kinds of cases. The model was revised and improved from the intensive analysis of six cases. The resulting model can be a useful guide for family therapists in that it describes the specific client and therapist behaviors involved in balancing the alliance, as well as the potential obstacles and suggested ways to resolve them.