Insulin receptor substrate 2 is a negative regulator of memory formation

Insulin has been shown to impact on learning and memory in both humans and animals, but the downstream signaling mechanisms involved are poorly characterized. Insulin receptor substrate-2 (Irs2) is an adaptor protein that couples activation of insulin- and insulin-like growth factor-1 receptors to downstream signaling pathways. Here, we have deleted Irs2, either in the whole brain or selectively in the forebrain, using the nestin Cre- or D6 Cre-deleter mouse lines, respectively. We show that brain- and forebrain-specific Irs2 knockout mice have enhanced hippocampal spatial reference memory. Furthermore, NesCreIrs2KO mice have enhanced spatial working memory and contextual- and cued-fear memory. Deletion of Irs2 in the brain also increases PSD-95 expression and the density of dendritic spines in hippocampal area CA1, possibly reflecting an increase in the number of excitatory synapses per neuron in the hippocampus that can become activated during memory formation. This increase in activated excitatory synapses might underlie the improved hippocampal memory formation observed in NesCreIrs2KO mice. Overall, these results suggest that Irs2 acts as a negative regulator on memory formation by restricting dendritic spine generation.     

Coherence of Personal Narratives across the Lifespan: A Multidimensional Model and Coding Method

Personal narratives are integral to autobiographical memory and to identity, with coherent personal narratives being linked to positive developmental outcomes across the lifespan. In this article, we review the theoretical and empirical literature that sets the stage for a new lifespan model of personal narrative coherence. This new model integrates context, chronology, and theme as essential dimensions of personal narrative coherence, each of which relies upon different developmental achievements and has a different developmental trajectory across the lifespan. A multidimensional method of coding narrative coherence (the Narrative Coherence Coding Scheme or NaCCS) was derived from the model and is described here. The utility of this approach is demonstrated by its application to 498 narratives that were collected in six laboratories from participants ranging in age from 3 years to adulthood. The value of the model is illustrated further by a discussion of its potential to guide future research on the developmental foundations of narrative coherence and on the benefits of personal narrative coherence for different aspects of psychological functioning.     

I'm feeling lucky: the relationship between affect and risk-seeking in the framing effect

Engagement in risky behavior has traditionally been attributed to an underestimation of the associated risks, but recent perspectives suggest that affective reactions toward a risky option may better explain risk-seeking than risk perception. However, the precise relationship between emotion and risk-seeking remains unclear. The current set of studies elucidates the relationship between emotion and risk-seeking in risky choice framing, using a gambling task. In Study 1, reliance on emotion was related to risk-seeking, but goals to regulate emotion mitigated these effects. In Study 2, positive affect was associated with risk-seeking in loss frames, but unrelated to risk aversion in gain frames. Collectively, these findings indicate a general role for emotion reliance on risk-seeking and a specific role of positive affect on risk-seeking in the loss trials of the framing effect.     

Children's memory for the times of events from the past years

This study tested 8–12‐year‐olds' ability to localize in time parent‐reported events from four time intervals ranging from 6 months to 4 years ago. Memory for content was very accurate, and children's time estimates showed substantial agreement with the times provided by their parents. Accuracy of year judgments declined with retention interval, with the greatest change occurring between the 1–2‐year and 2–3‐year intervals. Season, month and time of day accuracy were much more stable over time. There were significant improvements with age in performance on measures of conventional time knowledge, and this performance was correlated with the accuracy of time estimates on the long time scales, controlling for age and general cognitive ability. Copyright © 2010 John Wiley & Sons, Ltd.     

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.     

What a Difference Family-Driven Makes: Stories of Success and Lessons Learned

Community Psychology’s emphasis on citizen participation aligns with the nationwide children’s mental health family movement and is clearly evident in communities that have made sustainable system changes. The national family movement has long advocated for the meaningful engagement of families and youth who are the focus population of the federal Children’s Mental Health Initiative. Little rigorous research about the experience of families in leadership positions or of their impact on systems of care has been done. In the absence of scientifically acquired evidence, this article offers the reader a glimpse into the authority, influence and credibility earned by four family leaders as well as their impact on local system of care communities. Their stories occur in four distinct macro level arenas: governance, evaluation, legislative advocacy, and workforce development. In the end, common attributes emerge from their stories, providing anecdotal information useful to identifying the qualities of successful family leadership and their impact on sustainable macro level changes.     

Diverse Perceptions of the Informed Consent Process: Implications for the Recruitment and Participation of Diverse Communities in the National Children’s Study

We examined the experiences, perceptions, and values that are brought to bear when individuals from different ethnic and cultural backgrounds consider participating in health research. Fifty-three women from Latino, Asian American, Middle Eastern, or Non-Latino, White backgrounds participated in seven English or Spanish focus groups facilitated by trained investigators using a standard protocol. Investigators described the National Children’s Study (NCS) and then asked questions to elicit potential concerns, expectations, and informational needs. Group sessions were audio-recorded, transcribed verbatim, and analyzed using qualitative thematic methods. A major theme that emerged during focus groups was participant self-identification as a member of a cultural group or community when raising issues that would influence their decision to participate in research. A related theme was the belief by some that communities may differ in the ease of participation in the NCS. Identified themes related to the informed consent process included perceived risks, anticipated burden, perceived benefits, informational needs, and decision-making strategies. Although themes were shared across groups, there were cultural differences within themes. Findings indicated that individuals from diverse backgrounds may have different perspectives on and expectations for the research process. To effectively recruit representative samples, it will be important to address a range of issues relevant for informed consent and to consider the impact of participation on both individuals and communities.