Learn More
Estrogen deficiency in postmenopausal women is associated with changes in physiological processes. The extent to which estrogen loss is associated with cognitive changes noted by postmenopausal women has been more difficult to determine for a variety of reasons. Primate models of menopause are now being used to determine the effects of estrogen loss and(More)
Aging produces changes in a variety of neural systems that result in a distinct neuropsychological profile of cognitive deficits. To determine the extent of functional decline in cognition with aging, the authors assessed attentional ability in adult (10-15 years old) and aged (28-33 years old) rhesus monkeys (Macaca mulatta) in 3 experiments, using a(More)
This chapter has been organized empirically, focusing on the types of approaches that have been taken to understand BFCS function. This approach reflects the state of our knowledge about the behavioral and psychological functions of the BFCS. Considerable information has been gathered in the very short time that the BFCS has been the object of intense(More)
Three monkeys were trained to remember colored photographs of objects over delays of 0, 15, 30, and 45 s. Then two pairs of cooling devices were implanted bilaterally over the anterior 9 mm of the temporal lobe. The devices consisted of 3 X 10 mm loops of stainless steel tubing into which cooled methanol could be pumped. One pair (anterior pair) covered the(More)
The present study examined the long-term (2 years) effects of estrogen loss or estrogen replacement therapy (ERT) on cholinergic neurons in the nucleus basalis of Meynert and on cholinergic fibers in the prefrontal and parietal cortex of adult female cynomolgus monkeys. Cholinergic fiber density in layer II of the prefrontal cortex was decreased in monkeys(More)
Caloric restriction (CR) reduces the pathological effects of aging and extends the lifespan in many species, including nonhuman primates, although the effect on the brain is less well characterized. We used two common indicators of aging, motor performance speed and brain iron deposition measured in vivo using MRI, to determine the potential effect of CR on(More)
In the present study, we compared the morphology and distribution of neurons expressing GnRH gene transcripts in the hypothalamus and forebrain of the cynomolgus monkey to that of the human. As in the human, three subtypes of GnRH neurons were identified. Type I GnRH neurons were small, oval cells with high levels of gene expression and were located within(More)
Cognitive impairments in humans and animals have been linked to dysfunction of neurons in the basal forebrain cholinergic system (BFCS). Degeneration of these cells may be, in part, responsible for some of the cognitive deficits observed in Alzheimer's disease (AD). Although memory deficits are associated with lesions of the BFCS in rats, impairments in(More)
Cold was used to suppress the function of subdivisions of the inferotemporal cortex. Three cryodes were placed bilaterally, one over the lower bank of the superior temporal sulcus (sts), one over the middle temporal gyrus (mtg) and one over the inferior temporal gyrus (itg). The animals were tested with delayed match-to-sample (DMS) and simultaneous visual(More)
The cholinergic hypothesis of memory dysfunction originally proposed that dysfunction of cholinergic neurons in the basal forebrain cholinergic system (BFCS) may be responsible for the memory deficits associated with aging and Alzheimer's disease (AD). This hypothesis directed focus on the BFCS in experimental animal models of AD. In contrast to numerous(More)