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41.
J. A. Joseph 《Integrative psychological & behavioral science》1992,27(3):216-227
One of the hallmarks of the aging process is a loss of sensitivity in central neuronal receptors to agonist stimulation. This
appears to be especially true in central (hippocampal, striatal) muscarinic cholinergic systems and in the striatal dopamine
systems. For these two systems, any decline in their sensitivity can be of extreme importance in determining the behavioral
capabilities of the organism. Decrements in the striatal dopamine system may be reflected as motor behavioral deficits, while
the central cholinergic systems play a major role in the processing of memory through the activation of muscarinic receptors
(mAChR). Declines in the function of these receptors appear to be at least partially responsible for the marked deterioration
of cognitive function in normal aging and, more notably, in Alzheimer’s disease (AD). Previous work has indicated only minimal
success in improving performance in tasks that assess memory in senescent animals or humans with pharmacological agents which
enhance cholinergic functioning. The present review describes research that indicates that two of the factors involved in
this decline in receptor sensitivity include: (a) decreased receptor concentrations and (b) age-related decrements in signal
transduction pathways. Studies are reviewed that indicate that the oxidative neural damage that occurs via kainic acid or
ionizing radiation parallel those seen in aging. It is suggested that the common mechanism that may exist among all of the
age-, disease-, excitatory amino acid- or radiation-induced deficits in neuronal transmission may involve free-radical-mediated
alterations in membrane integrity through lipid peroxidation. 相似文献
42.
43.
44.
Irvin Sam Schonfeld David Shaffer Joseph E. Barmack 《Journal of abnormal child psychology》1989,17(6):575-596
A group of 115 black male adolescents drawn from a clinically unselected birth cohort, half of whom were known to have had neurological soft signs at age 7, were examined at age 17 to determine the relation between soft signs and performance on standard tests of school achievement and sustained attention. Three signs measured at age 17-dysgraphesthesia, difficulties with rapid alternating movements (dysdiadochokinesis), and motor slowness—were related to lower concurrent and past IQ and to impaired performance on laboratory and paper-and-pencil measures of sustained attention. The relation between signs and the attentional measures remained significant after IQ was statistically controlled. The three age 17 soft signs as well as age 7 signs were related to impaired performance on standardized tests (age 17) of school achievement. Most of the relation between signs and school achievement could be accounted for by the variance signs shared with sustained attention. One sign, mirror movements, was unrelated to all other attentional and cognitive measures.The study was supported by center grant MH 306906 and research training grant 5 T32 MH 13043-13 from the National Institute of Mental Health, as well as by the City College and the City University Computing Centers. We thank Lillian Belmont and two reviewers for their critical comments on an earlier version of the paper. We dedicate this paper to the memory of Joseph Barmack. 相似文献
45.
The Additive Factor Method: A differential diagnostic tool in hyperactivity and learning disability 总被引:1,自引:0,他引:1
Jaap van der Meere Maarten van Baal Joseph Sergeant 《Journal of abnormal child psychology》1989,17(4):409-422
The Additive Factor Method assumes that task performance is the sum of sequential and independent processes. We studied the duration of the central processes (memory search and decision) and the motor decision process in hyperactive and learning-disabled children under socalled divided attention and S-R compatibility conditions. It was found that the learning-disabled were impaired in memory search and decision processes whereas hyperactives were impaired in the motor decision process.The authors wish to thank L. Leertouwer for making the drawings. 相似文献
46.
The study was designed to examine the influence of significant others (mothers, fathers, and male and female peers) on continuing involvement in sport by adolescent females. Survey data were collected from 376 girls using a forced-choice, self-administered questionnaire. Maintenance of involvement was measured by the proportion of possible years in which the respondents were involved in physical activity within each of three participation contexts (intramural, interschool, and community sport). Several indicators of significant other influence were used. The degree to which involvement in physical activity is maintained is positively related to the source, amount and type of influence received from significant others, and varied by the participation context. Overall, the socializing influence of significant others was able to account for 11% of the variance in intramural activity, 20% of the variance in interschool sport, and 10% of the variance in community-based activity.This study was funded by a grant from Fitness Canada. 相似文献
47.
48.
Edmond A. Murphy Kenneth R. Berger Joseph E. Trojak E. Manuel Rosell 《Theoretical medicine and bioethics》1989,10(4):355-365
Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated. 相似文献
49.
Jerry M. Lewis J. M. Rabbie Thomas Berg Michael Argyle Karin Aronsson Roger Ingham Neil Frude A. M. Munton Duncan Cramer John Shotter Ray Holland Nobleza Asuncion-Lande Ray Crozier Candida Peterson Chris Spencer Victor J. Callan Jack Martin N. L. Reinsch Anthony Ryle David Canter Jill Robson H. R. Beech Duncan Moss David Fontana Tom Richards 《Current psychology (New Brunswick, N.J.)》1989,8(1):49-87
50.