Interactive effects of APOE and CHRNA4 on attention and white matter volume in healthy middle-aged and older adults

In the present study, we investigated age-related changes in interactions between efficiency of neuronal repair mechanisms and efficiency of cholinergic neurotransmission in the context of attentional orienting. In addition, we explored white matter volume changes as possible neuronal underpinnings. A sample of 230 healthy middle-aged (53–64 years) and older (65–75 years) adults was genotyped for polymorphisms of APOE and CHRNA4, a nicotinic receptor subunit gene. Participants were administered a visuospatial attention task involving letter discrimination with location cues of varying validity. Genotype effects on white matter volume were also investigated in a subset of participants who received MRI scans. APOE interacted with CHRNA4, such that APOE-ε4 carriers who were also CHRNA4 TT homozygotes showed disproportionately slowed reaction time (RT) following invalid location cues. The interaction was stronger in the middle-aged participants than in the older participants. There was also a trend for individuals with combined APOE-ε4/CHRNA4 TT genotypes to show both lower white matter volume and slower overall RT on the attention task. The interaction of a neurotransmission gene (CHRNA4) and a susceptibility gene (APOE) suggests that the efficiency of neuronal repair mechanisms may modulate the cholinergic system to influence attentional function.     

“It can save you if you just forget”: Closeness and Competence as Conditions for Coping among Ugandan Orphans

This article explores the coping strategies of orphaned children and their caregivers supported by a community-based organization in a Ugandan slum area. In-depth qualitative interviews were conducted with eight orphans (aged 12 to 16 years) and their caregivers selected by the community-based organization. The children had experienced several co-occurring risk factors such as loss and separation, poverty, disease, and an unsafe environment. Most caregivers were extended family members. One caregiver was an unrelated foster carer. Three of the households were child-headed. Data were analysed using an adapted approach of Giorgio's (Hafting, 1995; Malterud, 2001) psychological-phenomenological method. Participating children from child-headed households lacked protective factors associated with closeness (i.e., supportive dyadic relationships). All the children in the study experienced competence in the arenas of school and household chores. Cultural advice on handling adversity, including ‘forgetting’, ‘accepting’ and ‘adjusting’, appears to contradict Western theories of coping. Sommerschild's theoretical model on the conditions for coping was effective in identifying conditions in children's lives that may impair their coping, self-worth, and resilience.     

Factors affecting career retention among naval aviators

Typically, retention studies have emphasized those who separate rather than those who choose a naval career. The present study examined factors that contribute to career satisfaction and aviators' decisions to remain in naval aviation. Primary reasons for remaining in naval aviation were the enjoyment of flying, coupled with the self-esteem associated with being a naval aviator. Career satisfaction for aviators was derived primarily from intrinsic motivators associated with flying and peer recognition.Opinions or conclusions contained in this report are those of the authors and do not necessarily reflect the views or the endorsement of the Navy Department. The research reported in this paper was completed under Naval Medical Research and Development Command work unit 63706N M0096 M00960.01.