Plasticity for Affective Neurocircuitry: How the Environment Affects Gene Expression

ABSTRACT— We ( Fox et al., 2005 ) recently described a gene-by-environment interaction involving child temperament and maternal social support, finding heightened behavioral inhibition in children homozygous or heterozygous for the serotonin transporter (5HTTLPR) gene short allele whose mothers reported low social support. Here, we propose a model, Plasticity for Affective Neurocircuitry, that describes the manner in which genetic disposition and environmental circumstances may interact. Children with a persistently fearful temperament (and the 5HTTLPR short allele) are more likely to experience caregiving environments in which threat is highlighted. This in turn will exacerbate an attention bias that alters critical affective neurocircuitry to threat and enhances and maintains anxious behavior in the child.     

Retelling urban legends

We explored factors influencing the retelling of urban legends. As predicted by prior work, people retold truthful and scary stories. But people also retold well-known stories. This contrasts with the expectation that people would not pass on a story that everyone already knew. Also as predicted by prior work, repeating a story increased its credibility. But repeating also increased a story's importance, scariness, and likelihood of retelling. In general, contextualizing a story and increasing the number of details did not affect the likelihood of retelling a story. The exception was that details increased the likelihood of retelling a newly heard story. However, if people read a story with context or details, more contextual elements and details were included in their retellings. At the same time, people confabulated details to an equal degree no matter what type of embellishments they had read.     

Beliefs about personality change and continuity

Lay conceptions of personality change and continuity were examined in a sample of 112 undergraduates. Participants rated their personal change over 5 years (past or future), the change they perceived to be normative over 10-year age spans between 15 and 65, their beliefs about whether personality is fixed or malleable (“lay theories”) and their beliefs about the causes of personality change and continuity. Beliefs about normative personality change generally corresponded to research evidence on adult trajectories of the Big Five factors, with some age bias, whereas recalled and anticipated personal change tended to be more positive than these norms. Participants tended to endorse environmental causes more for personality change than for continuity. Lay theories were not consistently associated with these causal beliefs, or with beliefs about personal and normative change.     

Dispositional affect and work-related stress.

Trait negative affectivity (NA) has been asserted to be a factor that spuriously inflates relationships between self-reported stressors and self-reported strain outcomes. We tested this hypothesis with conventional work stress instrument responses and physiological assessments obtained from 311 fire and police department employees. Confirmatory factor analyses indicated that NA did not measure a factor in common with measures of subjective strain. Latent-variable structural equations analyses, however, found that estimating the effects of NA on strain significantly attenuated the effects of work stressors. NA had no correlation with physiological stress outcomes. Trait positive affectivity did not attenuate relationships between work stressors and either subjective or objective stress outcomes. Implications for work stress research methodology and recommendations are discussed.     

Interactional Reconstruction in Real-Time Language Processing

This study documents and characterizes a phenomenon in naturally-occurring conversation which I have termed interactional reconstruction. Interactional reconstruction involves retroactive reinterpretation of an earlier utterance (or set of utterances) on the basis of a more recent utterance (or set of utterances). This work is meant to serve two functions: first, to enrich our theories of human communication; and second, to explore directions and implications for theories of meaning and discourse modeling within cognitive science.     

Wild hummingbirds rely on landmarks not geometry when learning an array of flowers

Rats, birds or fish trained to find a reward in one corner of a small enclosure tend to learn the location of the reward using both nearby visual features and the geometric relationships of corners and walls. Because these studies are conducted under laboratory and thereby unnatural conditions, we sought to determine whether wild, free-living rufous hummingbirds (Selasphorus rufus) learning a single reward location within a rectangular array of flowers would similarly employ both nearby visual landmarks and the geometric relationships of the array. Once subjects had learned the location of the reward, we used test probes in which one or two experimental landmarks were moved or removed in order to reveal how the birds remembered the reward location. The hummingbirds showed no evidence that they used the geometry of the rectangular array of flowers to remember the reward. Rather, they used our experimental landmarks, and possibly nearby, natural landmarks, to orient and navigate to the reward. We believe this to be the first test of the use of rectangular geometry by wild animals, and we recommend further studies be conducted in ecologically relevant conditions in order to help determine how and when animals form complex geometric representations of their local environments.     

Newborn Screening: Education,Consent, and the Residual Blood Spot. The Position of the National Society of Genetic Counselors

Newborn screening (NBS) is a minimally invasive lifesaving test. There is currently no federal mandate for NBS, thus states determine their own screening panel based on the recommendations of the Secretary’s Advisory Committee on Heritable Disorders in Newborn and Children (SACHDNC), which was recently re-chartered as the Discretionary Advisory Committee on Heritable Disorders in Newborns and Children (DACHDNC). After NBS is completed, a couple of residual blood spots remain. While some states allow these spots to be used for public health and scientific research purposes, parents are not always informed about these additional uses. This paper addresses the National Society of Genetic Counselors’ (NSGC’s) position about NBS and blood spot storage/use and the rationale for these positions. The National Society of Genetic Counselors strongly supports newborn screening for the uniform screening panel of conditions recommended by the Secretary’s Advisory Committee on Heritable Disorders in Newborns and Children. NSGC also supports storage and use of blood spot samples by newborn screening laboratories and transparent policies that govern these activities.     

Minimal Risk of Internalizing Problems in Typically-Developing Siblings of Children with High-Functioning Autism Spectrum Disorder

We examined anxiety and depression clinical symptom levels in 42 typically-developing (TD) siblings of children with high-functioning autism spectrum disorder (HFASD), compared to 42 TD siblings of TD children, matched on age, ethnicity, and gender. Participants were between the ages of 6 and 16. Groups were compared using the parent-report and child self-report versions of the Behavior Assessment System for Children, Second Edition, anxiety and depression clinical scales. Within-group differences were examined for parent versus child ratings. Multivariate procedures did not support clinically elevated levels of internalizing problems in siblings of children with HFASD. Results from both sources were consistent with the overall finding. The findings do not support an increased need for targeted intervention, though clinical and school-based practitioners should attend to clinical warning signs if presented.