James G. Herndon

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Although cognitive decline has been well established as a consequence of aging in non-human primate models, the prevalence or frequency of impairment for specific age ranges has not been described. The first aim of this study was to estimate prevalence of cognitive impairment on each of the six tests of cognitive performance by comparing the performance of(More)
This study investigated the effects of different rearing conditions on neural and cognitive development of male rhesus monkeys (Macaca mulatta). Infants raised individually in a nursery from 2 to 12 months of age (NURSERY, n=9) were compared to age-matched infants raised in a semi-naturalistic, social environment (CONTROL, n=11). Various brain regions were(More)
Heterologous prime/boost regimens have the potential for raising high levels of immune responses. Here, we report that DNA priming followed by a recombinant modified vaccinia Ankara (rMVA) booster has controlled a highly pathogenic immunodeficiency virus challenge in a Rhesus macaque model. Both the DNA and rMVA components of the vaccine expressed multiple(More)
As part of the effort to characterize age-related cognitive changes in executive system function in a nonhuman primate model of human aging, the performance of seven rhesus monkeys, 20 to 28 years of age, was compared to that of five young adult monkeys, 6 to 11 years of age, on spatial and object reversal tasks. No differences in performance were found(More)
Aged rats recover poorly after unilateral stroke, whereas young rats recover readily possibly with the help from the contralateral, healthy hemisphere. In this study we asked whether anomalous, age-related changes in the transcriptional activity in the brains of aged rats could be one underlying factor contributing to reduced functional recovery. We(More)
Understanding the nature of changes in cognition with aging has increased in importance as the number of individuals over the age of 65 years grows. To date, studies have demonstrated that age-related changes occur most extensively in the cognitive domains of memory and executive function. Whereas a large number of studies have been conducted about the(More)
Studies on human postmortem material report lower brain weights in older than in younger cohorts, whereas there is no apparent change with age in the rhesus monkey. In view of these contrasting results, we examined the pattern of brain weight across the life span in the chimpanzee, one of the closest biological relatives of humans. To place the study in(More)
Assessment of recognition memory was performed on eight rhesus monkeys of advanced age (25 to 27 years of age) using the delayed recognition span test (DRST). Their performance was compared to that of five young adult animals (5 to 7 years of age) on two stimulus conditions of the DRST: spatial position and color. Both trial unique and repeating series were(More)
Estrogen deficiency following ovariectomy or menopause increases the risk of developing diseases such as osteoporosis and may also lead to memory impairment. Although estrogen replacement therapy (ERT) alleviates many symptoms associated with estrogen loss, it is not clear whether it also benefits cognitive function. The effect of estrogens upon cognition(More)
Twelve young (4-7 years of age) and 14 old (20-27 years of age) male and female rhesus monkeys were tested on seven cognitive tasks. Males and females performed similarly on tasks of object memory and executive function, but young males outperformed young females on a spatial memory task (Delayed Recognition Span Test) that requires the identification of a(More)