James D Churchill

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While limited research is available, evidence indicates that physical and mental activity influence the aging process. Human data show that executive functions of the type associated with frontal lobe and hippocampal regions of the brain may be selectively maintained or enhanced in humans with higher levels of fitness. Similarly enhanced performance is(More)
It has previously been demonstrated that the central somatosensory topographic reorganization within deprived cortex that follows peripheral nerve injury in adult monkeys occurs in at least two stages: an immediate unmasking period; and a more prolonged period where deprived areas of cortex come to express new receptive fields in a topographically arranged(More)
In adult monkeys with dorsal rhizotomies extending from the second cervical (C2) to the fifth thoracic (T5) vertebrae, cortex deprived of its normal inputs regained responsiveness to inputs conveyed by intact peripheral afferents from the face [T.P. Pons, P.E. Garraghty, A.K. Ommaya, J.H. Kaas, E. Taub, M. Mishkin, Massive reorganization of the primary(More)
Researchers and clinicians are increasingly recognizing that psychological and psychiatric disorders are often developmentally progressive, and that diagnosis often represents a point along that progression that is defined largely by our abilities to detect symptoms. As a result, strategies that guide our searches for the root causes and etiologies of these(More)
Enhanced proliferation of airway smooth muscle is thought to contribute to the pathogenesis of asthma and other obstructive airway diseases. Lysophosphatidic acid (LPA) is a simple bioactive lipid mediator that stimulates mitogenesis in fibroblasts and some other cell types. The effects of LPA on mitogenesis of cultured human airway smooth muscle cells were(More)
We have previously shown that most of the reorganization that typically follows median nerve transection in adult squirrel monkeys is dependent on normally functioning N-methyl-D-aspartate (NMDA) receptors. Here, we have evaluated two additional hypotheses: (1) is the immediate "unmasking" found after median nerve transection NMDA receptor-dependent? and(More)
A view that is emerging is that the brain has multiple forms of plasticity that must be governed, at least in part, by independent mechanisms. This view is illustrated by: (1) the apparent separate governance of some non-neural changes by activity, in contrast to synaptic changes driven by learning; (2) the apparent independence of different kinds of(More)
Topographic reorganization of central maps following peripheral nerve injury has been well characterized. Despite extensive documentation of these physiological changes, the underlying anatomical correlates have yet to be fully explored. In this study, we used Golgi impregnation and light microscopy to assess dendritic morphology following denervation of(More)
In the present experiments, we investigated the effects of several commonly employed antiepileptic drugs on the performance of adult rats in a Morris water maze task. We found that phenytoin treatment produced the most deleterious performance impairments across all days of training, and that these performance deficits are not likely due to any general(More)
Numerous types of age-related deficits in the nervous system have been well documented. While a distinction between general types of memories that are susceptible to compromise with advanced age has been fairly well agreed upon, it is often difficult to determine exactly which specific processes are detrimentally influenced. In this study, we used a(More)