Does the level at which cognitive change occurs change with age?

Increased age in adulthood is associated with systematically more negative cognitive change, but relatively little is known about the nature of change at different ages. The present study capitalized on the hierarchical structure of cognitive abilities to investigate possible age differences in the level at which change operates. Reductions in the longitudinal associations between test scores when across-time relations were specified at different levels in the hierarchical structure were used to infer contributions to change from the level of abilities and from the level of a general factor. Although the pattern of influences varied across different cognitive abilities, the results revealed little or no age differences in the relative contributions to change from different levels in the hierarchy.     

Influence of recollection and plausibility on age-related deficits in associative memory

Age-related declines in associative memory are proposed to result from deficits in older adults' ability to recollect the past. The present experiment investigated the ability of older adults to compensate for deficits in recollecting the past by using plausibility. Participants studied a list of word pairs that shared category or rhyme relations. To measure the processes used during the recognition memory test, participants provided self-reported explanations for their memory judgements. Older adults relied primarily on plausibility, and the younger adults relied on both plausibility and recollection. Older adults experienced both positive and negative consequences as a result of using a knowledge-based strategy to compensate for their decreased ability to recollect the past. Specifically, they were just as capable as younger adults at recognising previously studied items and correctly rejecting distractors that were inconsistent with the rule provided at study. However, they falsely recognised distractors that were consistent with that rule more often than younger adults.     

Skilled deaf readers have an enhanced perceptual span in reading

Recent evidence suggests that, compared with hearing people, deaf people have enhanced visual attention to simple stimuli viewed in the parafovea and periphery. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in parafoveal vision to preprocess upcoming words and decide where to look next. In the study reported here, we investigated whether auditory deprivation affects low-level visual processing during reading by comparing the perceptual span of deaf signers who were skilled and less-skilled readers with the perceptual span of skilled hearing readers. Compared with hearing readers, the two groups of deaf readers had a larger perceptual span than would be expected given their reading ability. These results provide the first evidence that deaf readers' enhanced attentional allocation to the parafovea is used during complex cognitive tasks, such as reading.     

Incremental validity of spouse ratings versus self-reports of personality as predictors of marital quality and behavior during marital conflict

The personality traits of neuroticism and agreeableness are consistently related to marital quality, influencing the individual's own (i.e., actor effect) and the spouse's marital quality (i.e., partner effect). However, this research has almost exclusively relied on self-reports of personality, despite the fact that spouse ratings have been found to have incremental validity over self-reports for a variety of other important outcomes. In a study of 300 middle-aged and older married couples, we examined the incremental validity of spouse ratings of neuroticism and agreeableness in predicting concurrent levels of self-reported marital quality, observations of behavior during a marital disagreement task, and depressive symptoms. Neuroticism and agreeableness had expected actor and partner effects on each of these outcomes. Spouse ratings of these traits demonstrated incremental validity in estimates of actor and partner effects on marital quality, marital behavior, and depressive symptoms. Results suggest that spouse ratings of personality may be important additions to the typical reliance on self-reports for research and clinical assessment in marriage.     

Chronic stress-induced alterations in mouse colonic 5-HT and defecation responses are strain dependent

Mood disorders and chronic stress are frequently associated with gastrointestinal (GI) symptoms including diarrhoea or constipation. Locally produced serotonin [5-hydroxytryptamine (5-HT)] regulates GI motility and is a key factor in the pathophysiology of stress-associated GI disorders. We aimed to establish whether chronic stress can differentially affect faecal output and colon 5-HT concentration in two inbred mouse strains: BALB/c and C57BL/6 which differ in their ability to cope with stress. Adult male BALB/c and C57BL/6 mice were restrained for 2?h daily for 10 days. Defecation was monitored during each stress session. Twenty-four hours after the last session of stress, plasma corticosterone concentration was higher than control in both strains, indicative of a physiological effect of chronic stress; however, stress-induced diarrhoea was more persistent in C57BL/6 mice. Basal concentration of colon 5-HT was higher in C57BL/6 mice, and stress elicited an increase in colon 5-HT only in this strain. Finally, na?ve BALB/c mice had a higher sensitivity (incidence of diarrhoea) to 5-HT (0.33?mg/kg, i.p.) than C57BL/6 mice. Our results suggest that differential defecation responses to stress may be associated with colon 5-HT concentration, which may in turn reflect the individual sensitivity to 5-HT. In addition, C57BL/6 mice emerge as a relevant model for studying GI alterations induced by chronic stress.     

Brain Development During the Preschool Years

The preschool years represent a time of expansive mental growth, with the initial expression of many psychological abilities that will continue to be refined into young adulthood. Likewise, brain development during this age is characterized by its ??blossoming?? nature, showing some of its most dynamic and elaborative anatomical and physiological changes. In this article, we review human brain development during the preschool years, sampling scientific evidence from a variety of sources. First, we cover neurobiological foundations of early postnatal development, explaining some of the primary mechanisms seen at a larger scale within neuroimaging studies. Next, we review evidence from both structural and functional imaging studies, which now accounts for a large portion of our current understanding of typical brain development. Within anatomical imaging, we focus on studies of developing brain morphology and tissue properties, including diffusivity of white matter fiber tracts. We also present new data on changes during the preschool years in cortical area, thickness, and volume. Physiological brain development is then reviewed, touching on influential results from several different functional imaging and recording modalities in the preschool and early school-age years, including positron emission tomography (PET), electroencephalography (EEG) and event-related potentials (ERP), functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS). Here, more space is devoted to explaining some of the key methodological factors that are required for interpretation. We end with a section on multimodal and multidimensional imaging approaches, which we believe will be critical for increasing our understanding of brain development and its relationship to cognitive and behavioral growth in the preschool years and beyond.     

Civilian Response Corps Force Review: The Application of Multi‐Criteria Decision Analysis to Prioritize Skills Required for Future Diplomatic Missions

Created by the State Department's Office of the Coordinator for Reconstruction and Stabilization, the Civilian Response Corps (CRC) contains a diverse pool of qualified and ready‐to‐deploy civilian professionals that support conflict prevention and response efforts in countries or regions that are at risk of, are currently in, or are transitioning from conflict or civil strife. As such, it is vital to optimize the CRC's skill groupings to maximize adaptability and responsiveness to highly uncertain and trying political conditions and crises across the globe. The nature of the CRC value proposition is such that determining which skill set compositions deliver the greatest benefit requires a multi‐faceted perspective that looks at a number of attributes and factors, both tangible and intangible. To meet these needs, an organizational decision‐making approach utilizing multi‐criteria decision analysis (MCDA) was applied to ensure that skill‐grouping allocations were determined in a logical and robust manner. The MCDA analysis allowed for a wide range of worldviews and perspectives, drawn from select members of academia and partner agencies of the CRC who provided their expert opinions on the expected demand for skill groupings commonly identified as most necessary in a civilian ‘surge’ capacity. These skills were assessed with reference to a values hierarchy of representative country scenarios, missions and sub‐missions identified by the Office of the Coordinator for Reconstruction and Stabilization. Of particular interest was the use of the MCDA method to prioritize CRC skill groupings and to help inform the Department of State's understanding of the ‘ideal’ proportion and types of civilian skills for inclusion in the CRC. Copyright © 2012 John Wiley & Sons, Ltd.     

Parent Participation Within Community Center or In-Home Outreach Delivery Models of the Early Risers Conduct Problems Prevention Program

A variety of predictors of parent participation in prevention programming have been identified in past research, but few studies have investigated how those predictors may vary by implementation context. Patterns of parent participation were examined in the Early Risers Conduct Problems Prevention Program using two family-focused service delivery models: a community center model (Center) and an in-home outreach-based model (Outreach). An ethnically diverse sample of Kindergarten through second grade students (n = 246) displaying elevated levels of aggression were recruited for the study and randomly assigned to either the Center (n = 121) or Outreach (n = 125) models. In both delivery models, participants and their families completed an assortment of baseline measures and received family skills and child skills intervention components and family- and school-based case management. Parents in the Center model demonstrated greater overall participation in family-focused components of the intervention. Parent motivation with parent-focused expectancies for the intervention represented the strongest predictor of parent participation across both delivery models. Family income differentially predicted parent participation across the two models, with low income predicting greater participation in the Center model and lower participation in the Outreach model. A qualitative finding emerged showing that parents receiving parent skills in the Center model via groups preferred to learn skills related to facilitating overall family relationships, whereas parents receiving parent skills via individual Outreach meetings preferred to improve a child’s behavior and emotion skills. Implications are discussed for the design of prevention programming in order to maximize parent participation in high risk populations.     

Adult mice maintained on a high-fat diet exhibit object location memory deficits and reduced hippocampal SIRT1 gene expression

Mounting evidence has established that diet-induced obesity (DIO) is associated with deficits in hippocampus-dependent memory. The bulk of research studies dealing with this topic have utilized rats fed a high-fat diet as an experimental model. To date, there has been a paucity of research studies that have established whether the memory deficits exhibited in DIO rats can be recapitulated in mice. Moreover, the majority of experiments that have evaluated memory performance in rodent models of DIO have utilized memory tests that are essentially aversive in nature (i.e., Morris water maze). The current study sought to fill an empirical void by determining if mice maintained on a high-fat diet exhibit deficits in two non-aversive memory paradigms: novel object recognition (NOR) and object location memory (OLM). Here we report that mice fed a high-fat diet over 23 weeks exhibit intact NOR, albeit a marked impairment in hippocampus-dependent OLM. We also determined the existence of corresponding aberrations in gene expression within the hippocampus of DIO mice. DIO mice exhibited significant reductions in both SIRT1 and PP1 mRNA within the hippocampus. Our data suggest that mice maintained on a high-fat diet present with impaired hippocampus-dependent spatial memory and a corresponding alteration in the expression of genes that have been implicated in memory consolidation.