In search of the language switch: An fMRI study of picture naming in Spanish-English bilinguals

For many years, researchers investigating the brain bases of bilingualism have concentrated on two basic questions. The first concerns the nature of language representation. That is, are a bilinguals' two languages represented in distinct or overlapping areas of the brain. The second basic question in the neuropsychology of bilingualism concerns the neural correlates of language switching, that is, the areas that are active when bilinguals switch from one language to the other. Performance between single-language and dual-language picture naming was compared in a group of six Spanish-English bilinguals using behavioral measures and functional magnetic resonance imaging. Participants showed slower reaction times and increased activation in the dorsolateral prefrontal cortex in the mixed language condition relative to single language condition. There was no evidence that each language was represented in different areas of the brain. Results are consistent with the view that language switching is a part of a general executive attentional system and that languages are represented in overlapping areas of the brain in early bilinguals.     

Enkephalins and learning and memory: a review of evidence for a site of action outside the blood-brain barrier

A series of studies indicate that enkephalins exert dramatic influences on learning and memory in rats and mice, when studied with conditioning tasks that are both negatively and positively motivated. Pharmacological analysis of these enkephalin actions on conditioning suggests that the [leu]enkephalin acts through a delta opioid receptor which is located outside the blood-brain barrier. Control studies indicate that enkephalins do not simply affect the performance of a conditioned response through actions on shock sensitivity or locomotor activity. Characterization of the peripheral enkephalin mechanism that affects behavior suggests an action through an enzymatic system that controls the concentrations of enkephalin present at its receptors in the periphery. This enzymatic mechanism is sensitive to experience, since its activity changes following conditioning, which suggests that it may be a regulatory mechanism for behavior.     

Physiological responses of obese subjects to external stimuli

Physiological arousal was measured in 11 obese and 11 normal-weight subjects during presentation of emotive, food, and neutral stimuli. No differential arousal (heart rate, temperature, GSR, and EMG on frontalis muscle) between the groups was obtained for any of the three types of stimuli. Discrepancies between the present findings and earlier results are discussed.     

Social stimuli increase physiological reactivity but not defensive responses

Emotional reactions are crucial in survival because they provide approach and withdrawal behaviors. However, an unsolved question is whether the social content of the affective stimuli has a specific effect on emotional responses. We studied whether the social content of affective pictures influenced the defensive response and response mobilization. For this purpose, we recorded startle blink reflex (a defensive response) and skin conductance responses (a measure of unspecific physiological reactivity or arousal) in 73 participants while they viewed a series of 81 pictures of varying affective valence and social content. Our results revealed that defense response, as indicated by increases in the magnitude of the startle blink reflex, was mainly dependent on threatening or unpleasant cues, but was unrelated to the social content of the pictures. The social content, however, had an influence on pleasant stimuli, provoking an increase in resource mobilization, as reflected by changes in electrodermal activity. Hence, the social content of the affective stimuli may increase the physiological arousal elicited by pleasant stimuli, and it appears to be unrelated to the defense reactivity provoked by unpleasant stimuli.     

Masculinity,Femininity, and Hispanic Professional Women's Self-Esteem and Self-Acceptance

The literature suggests that whereas women experience unique challenges with self-esteem, Hispanic professional women experience an additional challenge of balancing majority culture values with a more family-oriented ethnic identity. This study investigated differences in self-esteem, self-acceptance, masculinity, femininity, and locus of control among Hispanic professional women, non-Hispanic professionals, scientists, college students, clients, and victims of domestic violence. Masculinity scores were significantly higher for Hispanic professional women, and self-acceptance scores were significantly lower than for other women professionals.     

The Role of Whites in Lay Leadership Within Latino Churches

Latinos are the largest ethnoracial minority group in America, and Latino congregations play an important role in the lives of their members and communities. Yet, little research exists on these congregations. The current study provides an examination of the lay leadership structures and power dynamics within Latino congregations. Drawing from organizational ecology theory and the homophily principle as well as contemporary racial stratification literature, we propose competing hypotheses regarding the roles whites play within the lay leadership and power structures of Latino congregations. Utilizing a national multilevel data set, we find the persistence of white privilege existing within Latino congregations, as whites are more likely to hold lay leadership positions within these congregations than Latinos, despite their numeric minority status. Moreover, our results reveal that individual access to the decision‐making process in these congregations increases for both whites and multiracial individuals as the proportion of Latinos increases in their congregation. We further discuss the implications of these findings.     

Parent Emotion Expression and Autonomic-Linked Emotion Dysregulation in Childhood ADHD

Despite evidence that ADHD is associated with disruptions in emotion regulation, few studies have examined the biological correlates of emotion dysregulation among children with this disorder. Prior work has pointed to roles of the parasympathetic and sympathetic nervous system, as indexed via respiratory sinus arrhythmia (RSA) and cardiac pre-ejection period (PEP), respectively. Work in typically developing populations suggests that parenting behavior and parental emotion expression may shape the development of these systems. To date, a single study has examined the independent and interactive roles of autonomic nervous system functioning and parent emotion expression in youth with ADHD. This study seeks to extend that work. 86 children (42 with ADHD), aged 8–12 years, and a parent completed a parent-child interaction task, while electrocardiography and impedance cardiography data were recorded to derive RSA and PEP. Parent and child emotion word use (positive and negative valence) were coded from recordings of the task. Parents of youth with ADHD used fewer positive emotion words throughout the task. Additionally, throughout the task, children with ADHD engaged in excessive RSA withdrawal from baseline. Further, the association between RSA reactivity and ADHD diagnosis was moderated by parent positive emotion word use. Specifically, those with RSA augmentation and parents displaying high positive affect across the task conditions were least likely to have an ADHD diagnosis. If replicated and extended, these results support the use of interventions specifically designed to increase parental modeling of positive emotions, while simultaneously focusing on building emotion regulation skills in youth with ADHD.     

Psychological stress reactivates dextran sulfate sodium-induced chronic colitis in mice

Inflammatory bowel disease (IBD) is a chronic condition with alternating active and quiescent phases of inflammation. Stress has been suggested as a factor triggering a relapse of IBD. We investigated the role of repetitive psychological stress [water avoidance stress (WAS)] in reactivating colonic inflammation in a murine model of dextran sulfate sodium (DSS)-induced chronic colitis. Colitis was induced in C57BL/6 female mice by exposure to 3% DSS (5 days). During chronic inflammation(day 34), mice underwent repetitive WAS (1 h/day/7 days) and were given a sub-threshold concentration of DSS (1%, 5 days)or normal water to drink. At euthanasia (day 40), inflammatory parameters were assessed (colon inflammatory score, levels of inflammatory markers and histology). Mice with chronic colitis exposed to WAS had higher macroscopic and microscopic colonic inflammatory scores and levels of inflammatory markers (mainly IL-1beta, IL12p40 and CCL5) than non-stressed mice. Inflammatory responses were further enhanced by the presence of a sub-threshold concentration of DSS (1%). In mice without chronic inflammation, neither WAS nor 1% DSS, individually or in combination, elicited any inflammation. Hence stress, per se, reactivates a quiescent chronic inflammation, but does not initiate inflammation in healthy mice. Stress should be regarded as an environmental factor triggering IBD relapses in humans.