Emerging roles of epigenetic mechanisms in the enduring effects of early-life stress and experience on learning and memory

Epigenetic mechanisms are involved in programming gene expression throughout development. In addition, they are key contributors to the processes by which early-life experience fine-tunes the expression levels of key neuronal genes, governing learning and memory throughout life. Here we describe the long-lasting, bi-directional effects of early-life experience on learning and memory. We discuss how enriched postnatal experience enduringly augments spatial learning, and how chronic early-life stress results in persistent and progressive deficits in the structure and function of hippocampal neurons. The existing and emerging roles of epigenetic mechanisms in these fundamental neuroplasticity phenomena are illustrated.     

Enduring deficits in contextual and auditory fear conditioning after adolescent, not adult, social instability stress in male rats

Adolescence is a time of developmental changes and reorganization in the brain and stress systems, thus, adolescents may be more vulnerable than adults to the effects of chronic mild stressors. Most studies, however, have not directly compared stress experienced in adolescence to the same stress experience in adulthood. In the present study, adolescent (n=46) and adult (n=48) male rats underwent 16 days of social instability stress (daily 1h isolation and change of cage partners) or were non-stress controls. Rats were then tested on the strength of acquired contextual and cued fear conditioning, as well as extinction learning, beginning either the day after the stress procedure or 3 weeks later. No difference was found among the groups during the Training Phase of conditioning. Irrespective of the time between the social stress experience and fear conditioning, rats stressed in adolescence had decreased context and cue memory, and cue generalization compared to control rats, as measured by the percentage of time spent freezing in tests. Social instability stress in adulthood had no effect on any measure of fear conditioning. The results support the hypothesis that adolescence is a time of heightened vulnerability to stressors.     

The psychological impact of facial changes in scleroderma

The physical disabilities associated with scleroderma are well known but the psychological impact of the condition has received less attention. Few studies have examined appearance related issues, most notably of the face. The aim of this study is to evaluate the psychological impact of facial, aesthetic and functional changes in scleroderma. One hundred seventy-one patients with a clinical diagnosis of scleroderma were recruited into the study. Digital photographs were objectively graded into groups based on severity of disfigurement as judged by an observer. Facial movement was recorded using a modified House-Brackmann Grading Scale. Psychological evaluation comprised the Derriford Appearance Scale short-form (DAS), the Noticeability and Worry score and the Hospital Anxiety and Depression Scale (HADS). Severity of disfigurement predicted decreased mouth opening, the extent to which participants judged their appearance as noticeable to others, and the level of appearance-related concern as measured by the DAS24. There was an inverse relationship with age. Facial changes were ranked as the most worrying aspect of the condition. This study shows facial disfigurement impacts on patient with scleroderma independent of functional changes related to systemic disease. The major difficulty is with the perceived noticeably of the condition to other people and the resulting self-consciousness in social encounters.     

Generalization of posture training to computer workstations in an applied setting

Improving employees' posture may decrease the risk of musculoskeletal disorders. The current paper is a systematic replication and extension of Sigurdsson and Austin (2008), who found that an intervention consisting of information, real-time feedback, and self-monitoring improved participant posture at mock workstations. In the current study, participants worked in an applied setting, and posture data were collected at participants' own workstations and a mock workstation. Intervention in the mock setting was associated with consistent improvement in safe posture at the mock workstation, but generalization to the actual workstation was limited.     

Cognitive abilities explaining age-related changes in time perception of short and long durations

The current study investigated how the development of cognitive abilities explains the age-related changes in temporal judgment over short and long duration ranges from 0.5 to 30 s. Children (5- and 9-year-olds) as well as adults were given a temporal bisection task with four different duration ranges: a duration range shorter than 1 s, two duration ranges longer than 3 s (4-8 s and >15 s), and an intermediate duration range (1.25-2.5 s). Their cognitive abilities were also assessed using a series of neuropsychological tests. The results showed that temporal sensitivity improved with age for each duration range but that this improvement occurred earlier for the short durations than for the long durations. Furthermore, the results revealed that the age-related improvement in time sensitivity for the durations shorter than 1 s was explained by the development of short-term memory span, whereas that for long durations was explained by the development of attention/executive functions. To summarize, the development of the abilities required to process long durations seems to be explained mainly by the development of attentional resources.     

Scientists Negotiate Boundaries Between Religion and Science

Analysis of interviews with 275 natural and social scientists at 21 elite U.S. research universities suggests that only a minority of scientists see religion and science as always in conflict. Scientists selectively employ different cultural strategies with regards to the religion‐science relationship: redefining categories (the use of institutional resources from religion and from science), integration models (scientists strategically employ the views of major scientific actors to legitimate a more symbiotic relationship between science and religion), and intentional talk (scientists actively engage in discussions about the boundaries between science and religion). Such results challenge narrow conceptions of secularization theory and the sociology of science literature by describing ways science intersects with other knowledge categories. Most broadly the ways that institutions and ideologies shape one another through the agency of individual actors within those institutions is explored.