Memory in traumatic brain injury: The effects of injury severity and effort on the Wechsler Memory Scale‐III

This study examined the effects of traumatic brain injury (TBI) on Wechsler Memory Scale‐III (WMS‐III) performance. Since poor effort potentially contaminates results, effort was explicitly assessed and controlled using two well‐validated cognitive validity indicators, the Portland Digit Recognition Test (PDRT) and Reliable Digit Span (RDS). Participants were 44 mild TBI patients with good effort, 48 mild TBI patients with poor effort, and 40 moderate–severe TBI patients with good effort. A dose–response relationship between injury severity and WMS‐III performance was demonstrated. Effect size calculations showed that the good effort mild TBI patients did not differ from normal (average Cohen's d= 0.07) while moderate–severe TBI had a moderate effect on WMS‐III scores (average Cohen's d=?0.52). Consistent with previous literature, the moderate–severe TBI group scored the lowest on WMS‐III Visual indices. Effort had a larger effect than injury severity on WMS‐III scores (average Cohen's d=?1.27). Clinical implications of these findings are discussed.     

The Army National Guard in OIF/OEF: Relationships among combat exposure,postdeployment stressors,social support,and risk behaviors

With the continued operations in Iraq and Afghanistan, studies of the prevalence of posttraumatic stress disorder and related symptoms are now common. However, lacking is how these symptoms relate to precipitating conditions and the mitigating effects of social support on these symptoms. This is particularly relevant for reserve military personnel, who have been shown to be greater at-risk for postdeployment problems. The present study examined questionnaire data obtained from Army National Guard (ARNG) units immediately after their return from deployment to Iraq and Afghanistan during 2010 (N = 4329 soldiers in 50 units). Findings showed few soldiers displayed risk behaviors (i.e., daily alcohol use, use of illicit drugs, suicide thoughts, and physically threatening others) during and after deployment. Those most likely to have more postdeployment risk behaviors were also those who showed more risk behaviors during deployment. A substantial percentage of soldiers reported combat exposure, postdeployment negative emotions, and postdeployment loss of a personal relationship. These reported outcomes were all related to increased risk behaviors after deployment. The buffering effect of social support on postdeployment risk behaviors was equally evident when data were examined individually and when grouped by unit memberships. Implications of findings for future research, practice, and policies are discussed.     

A guide for the estimation of gender and sexual orientation effects in dyadic data: an actor-partner interdependence model approach

The study of gender differences is a pervasive topic in relationship science. However, there are several neglected issues in this area that require special care and attention. First, there is not just one gender effect but rather three gender effects: gender of the respondent, gender of the partner, and the gender of respondent by gender of the partner interaction. To separate these three effects, the dyadic research design should ideally have three different types of dyads: male-female, male-male, and female-female. Second, the analysis of gender differences in relational studies could benefit from the application of recent advances in the analysis of dyadic data, most notably the Actor-Partner Interdependence Model. Third, relationship researchers need to consider the confounding, mediating, and moderating effects of demographic variables. We use the American Couples (Blumstein & Schwartz, 1983) data set to illustrate these points.     

Measuring individualism and collectivism: The importance of considering differential components,reference groups,and measurement invariance

A new instrument of individualism and collectivism (I/C) was developed and three key issues in I/C measurement were addressed: differentiating components of I/C, understanding the impact of reference groups, and testing of measurement invariance. Three components of I/C were assessed in China and the U.S.: independence, competitiveness, and uniqueness for individualism; considering of one’s decisions on others, sharing of positive outcomes, and sharing of negative outcomes for collectivism. Collectivism was measured with respect to parents, friends, and general others. Results indicate that Chinese participants are less unique but more independent and competitive than their counterparts in the U.S. The expected cultural difference is found for parent collectivism across all three components and for sharing negative outcome with respect to all three reference groups. These results suggest that individualism is a multidimensional construct, whereas the dimensionality of collectivism appears to be a function of social distance. Measurement invariance was tested at configural, factor loading, and intercept levels for all components of I/C.     

Path dependent preferences: The role of early experience and biased search in preference development

What is the role of early experiences in shaping preferences? What are the mechanisms by which such early encounters influence the way preferences are formed? In this research, we examine the impact of the entry position and favorability of initial (and ongoing) experiences on preference development. We predict that the starting point will heavily influence which particular region people select from initially, and favorableness of early experiences and myopic search will both limit their search to that particular region. Across four studies, we find that when the initial experiences are favorable, subjects engage in lower levels of search, experience only a narrow breadth of possible alternatives, demonstrate less ongoing experimentation, and have a reduction in the amount of preference development.     

Word-list-learning performance in younger and older adults: intra-individual performance variability and false memory

We investigated the word-list-learning performance of younger and older adults over 4 consecutive days at different times of day to study age-related differences in consistency of performance over time and the influence of circadian variation on performance. Eighteen younger (M age, 23.4 years) and 18 older (M age, 73.3 years) men and women participated. The start time of testing alternated between morning and early evening across the 4 days of testing. On each test day, participants learned a different list of 15 unrelated words over four learning trials. As expected, younger adults performed better than older adults on immediate recall, delayed recall, and recognition. Contrary to our expectations, time of day did not significantly influence recall or recognition performance in either the older or younger adults. Older adults did show a greater incidence of false memory (i.e., previously learned list intrusions in free recall and false alarms in recognition) than younger adults. Older adults also exhibited greater intra-individual performance variability on the measures of false memory across test days. This variability was not related to circadian variation. False memory and variability of performance have both been linked to frontal systems dysfunction. The findings presented here are consistent with the notion that changes in cognition with aging in part reflect age-related decline in frontal lobe function.     

Object‐based visual processing in children with spina bifida and hydrocephalus: A cognitive neuropsychological analysis

The aim of the study was to use cognitive neuropsychological analysis to investigate object‐based visual processing skills in children with spina bifida myelomeningocele and hydrocephalus (SBH). Fourteen children with SBH (aged 8–12) and 21 age‐, socio‐economic status‐, and Verbal IQ‐matched healthy controls were assessed using the Birmingham Object Recognition Battery. Overall, the performance of the children with SBH on the object‐processing tasks was intact, indicating normal development of the ventral visual processing pathway. While the initial results indicated that the children with SBH performed statistically significantly less accurately on some tasks, these group differences no longer met significance criteria after capacity for sustained attention was statistically controlled.     

Goals-feedback conditions and episodic memory: Mechanisms for memory gains in older and younger adults

Research has established that challenging memory goals always lead to score increases for younger adults, and can increase older adults' scores under supportive conditions. This study examined beliefs and on-task effort as potential mechanisms for these self-regulatory gains, in particular to learn whether episodic memory gains across multiple trials of shopping list recall are controlled by the same factors for young and old people. Goals with feedback led to higher recall and strategic categorisation than a control condition. Strategy usage was the strongest predictor of gains over trials for both age groups. Age, goal condition, and effort also predicted scores across the entire sample. Older adults' gains, but not younger adults' gains, were affected significantly by the interaction of self-efficacy beliefs and goal condition, and condition interacted with locus of control to predict younger adult gains. These results emphasise the importance of self-regulatory effort and positive beliefs for facilitating goal-related memory gains.