Showing papers in "Experimental Aging Research in 1988"

Does the capacity of working memory change with age

Abstract: Young and elderly adults were compared for recall performance on simple digit and word spans (traditional tests of primary memory), versus a “loaded” auditory word span test designed to emphasize working memory capacity. Although digit spans were identical for the two age groups, there were small but significant age differences in word span, and even larger differences in working memory performance. An analysis of correlations between span measures and verbal ability scores supported the position that working memory loading represents a special problem for the elderly.

Characteristic difficulty in rhythmic movement with aging and its relation to Parkinson's disease.

Abstract: A total of 137 healthy participants aged from 20 to 79 years, including 59 over 60 years, were examined using a finger-tapping test. The test requested the participant to respond synchronously with the right middle finger to a periodic sound train with frequencies of 1, 2, 3, 4, and 5 Hz (cycles/sec). Difficulty keeping the rhythmic movement at a given rate was found to be a characteristic of aging. For the participants over 30 years, the mean rate of tapping deviated towards a faster rate for the stimulus frequency at 4 or 5 Hz (hastened tap, HT). The percentage of the participants who exhibited HT increased with decade of age; 0(20s), 11(30s), 13(40s), 17(50s), 30(60s) and 29(70s). HT in aging appears similar to hastened tapping which is typically observed in patients with Parkinson's disease and may be related to extrapyramidal dysfunction. Hastened tapping in the elderly supports the hypothesis that Parkinson's disease is a model for premature aging, suggesting that HT in aging represents an extrapyramidal motor dysfunction due to the neuroanatomical and neurochemical changes in the nigro-striatal system of the aging brain.

Subjective age, age identity, and middle-age adults

Abstract: A casual model of subjective age among middle-age working adults is proposed. Determinants of subjective age include chronological age, education, health, self-esteem, financial satisfaction, and job satisfaction. Life satisfaction is used as an explanatory outcome. Using a sample of middle-age men, the results indicate that self-esteem and financial satisfaction were important mediators between chronological age and subjective age. In turn, positive and negative characteristics were associated with both a "younger" and "older" subjective age. The results contribute to the further understanding of adult development and the meaning of subjective age.

Pretraining enhances mnemonic training in elderly adults.

Abstract: One hundred twenty-eight elderly adults were recruited to assess the effects of affective judgment, imagery, and relaxation pretraining on mnemonic training. Participants were assigned to one of the following conditions: (1) visual imagery and affective judgment pretraining plus mnemonic training, (2) visual imagery pretraining only plus mnemonic training, (3) relaxation pretraining plus mnemonic training, (4) nonspecific pretraining plus mnemonic training, (5) nonspecific pretraining only, and (6) wait list. Subjects were tested at three times: prior to training (Time 1), following pretraining (Time 2), and at the conclusion of mnemonic training (Time 3). Although those receiving active pretraining plus mnemonics did not differ from one another at Time 3, they recalled more than those with no active pretraining. The results suggest that for mnemonics to be effective they should be coupled with active pretraining techniques.

Self-recognition in senile dementia.

Abstract: Eighteen women with senile dementia of the Alzheimer type were observed in two situations of mirror-image stimulation, which were repeated after a 3-week interval. Six out of six subjects scoring 5 on the Global Deterioration Scale of Reisberg et al. reacted appropriately to an unfamiliar mark on their forehead when they observed it in the mirror, thus showing clear self-recognition. Fifty percent of the subjects at GDS 6 showed such evidence of self-recognition, and no subject at GDS 7 did so. In contrast, whereas 50% of GDS 5 subjects responded to a directly visible mark on the back of the hand, all GDS 6 subjects reacted to this mark. These results suggest that the capacity for self-recognition may start to be compromised by GDS stage 6, and that the eventual failure to show self-recognition in severe senile dementia cannot be dismissed in terms of a simple lack of motivation.

Studies of aging using genetically defined rodents: a bibliography.

Abstract: (1988). Studies of aging using genetically defined rodents: A bibliography. Experimental Aging Research: Vol. 14, No. 2, pp. 59-81.

Instructional variation and adult age differences in activity memory

Abstract: Recall of a series of 12 activities was compared for young and elderly subjects performing under four instructional conditions: incidental memory, standard intentional memory, intentional-emphasis, and interpolated recall (intermediate recall tests after every three activities had been performed). Relative to the incidental memory condition, superior recall was found for subjects in the intentional-emphasis and intentional-interpolated recall conditions. An age-related deficit in recall was found, but the Age x Instructional Condition interaction was not significant. Instructional variation was also found to affect temporal memory scores for the order in which the activities has been performed. An age-related deficit in temporal memory proficiency was found for all conditions except that of interpolated recall. On the other hand, instructional variation had a negligible effect on performance scores for the 12 specific activities.

Age differences in primary organization or processing variability? Part I: An examination of age and primary organization.

Abstract: We compared young and elderly adults on the ability to serially recall sequences of letters assumed to be stored in secondary memory. The results showed that older adults recalled significantly fewer complete strings than younger adults. However, both age groups exhibited the same pattern of transitional error probabilities (TEPs), indicating that the two groups were chunking information in the same qualitative manner. Interestingly, though, the older adults exhibited higher TEP spikes (indicating stronger chunk bounderies) than did younger adults. These results do not support the view that there are qualitative age differences in primary organization, but the results do indicate that older adults have a secondary memory deficit.

Age and context effects in lexical decision: An age by context interaction

Abstract: The present experiment demonstrates greater priming effects in a lexical decision task for older adults than for younger adults. Thirty-six older adults and thirty-six younger adults participated in a lexical decision experiment in which primes were category names and related targets were category exemplars that varied in category dominance. This manipulation of category dominance was intended to limit the predictability of target words based on prime words. Results showed that older adults had significantly greater priming effects than did younger adults. This outcome represents a departure from most studies of age effects on priming in lexical decision. It is suggested that older adults make greater use of context than younger adults when the context is of limited predictive value.

Beliefs about fact retrieval and inferential reasoning across the adult lifespan

Abstract: This study deals with beliefs about question-answering processes involving “world knowledge” utilized by young, middle aged, and older adults. Questions intended to induce either fact retrieval or inferential reasoning were shown to younger (n = 37), middle aged (n = 37) and older (n = 37) adults in both a multiple choice and true/false format. Increasing age level was not related to decreased confidence in either fact retrieval or inferential reasoning. Global assessments about these question-answering processes involving “people in general” and self evaluations were taken from the same individuals. In contrast to personal confidence ratings, adults of all ages generally believed in declining fact retrieval abilities in old age. Inferential reasoning, however, often was believed to remain stable or even increase in ability level with increasing age. This was especially true in the assessments generated by older adults and in self evaluations. Thus, negative global beliefs about memory and aging ...

Age differences in primary organization or processing variability? Part II: Evidence for processing variability.

Abstract: Young and older adults were compared on their ability to organize letter sets into "opaque" memory codes (letters were either transposed within or between imposed chunk boundaries on a secondary memory, recognition task). Also, processing variability (i.e., internal noise) was examined via signal detection methods. The data indicated that there were no qualitative age differences in the manner in which both groups organized opaque memory codes, although older adults did take significantly longer to respond. The results from the signal detection theory portion of the present experiment demonstrated that older adults' memory operating characteristic curves exhibited significantly more variability than those of the young. This suggested that an age difference in processing variability existed, rather than any appreciable age difference in the primary organization (i.e., the forming of opaque memory codes) of item order information.

The problem of naming in SDAT: A relative deficit

Abstract: Research relating to language disorder in senile dementia of the Alzheimer type (SDAT) has focused primarily on naming impairment, formally termed anomia or nominal aphasia/dysphasia. Data resulting from this research have been insufficiently informed by a comparative linguistic framework in which performance on naming tasks is contrasted with performance on other forms of language tasks. The present study involves the comparison of 21 adults with SDAT and 18 demographically controlled normal elderly adults on the Test for Syntactic Complexity and fifteen subtests of the Western Aphasia Battery. Performance on naming is compared with performance on oral language variables of repetition, yes/no response, auditory word recognition, sequential commands, syntactic processing, as well as with performance on reading tasks and non-verbal tasks. Findings relating to oral language tasks show that structured syntactic processing requiring explicit interpretation and sequential commands are significantly more difficult for the SDAT sample than are three of four naming tasks. Further, significant SDAT performance variability is found across naming tasks. The generative categorical naming task is found to be significantly more difficult for the SDAT patient than are the other three naming tasks. It is concluded that the generative categorical naming task should be regarded as a meta-naming task. In sum, it is found that although language dysfunction in SDAT has anomic components, the essential character of the language disorder is not best conceptualized as a problem of naming.

Genetic analyses of aging processes in Drosophila.

Abstract: Genetic investigations into the aging processes of Drosophila have a long history. Much of the earlier work attempted the analysis of longevity in already existing and (usually) short-lived strains and mutants, but was unsuccessful because there was no way of assuring that the genes involved actually affected the normal aging processes. Success was achieved only when procedures were devised to specifically select for mutants and/or strains affecting the normal aging processes. Recent work has shown that the life span may be genetically altered either via an acceleration of the normal aging rate or via the stage-specific lengthening of certain portions of the adult life span. A variety of evidence suggests that aging is best viewed as a genetically determined, environmentally modulated, event dependent process. The evidence underlying these observations is discussed, a possible genetic model is presented and future directions are suggested.

Hyperglycemia as a predictor for mortality in veterans with pneumonia.

Abstract: The elderly may have multiple problems including diabetes mellitus and pneumonia. This study was undertaken to evaluate the effect of hyperglycemia on the length of stay (LOS) and mortality of elderly veterans admitted for pneumonia. Forty-seven and forty-eight patients over the age of 60 admitted for the diagnosis of pneumonia at the Lexington, Kentucky and Iron Mountain, Michigan VAMC's respectively were evaluated. The mean age at Lexington was 72 and at Iron Mountain was 73.9. At Lexington the mean LOS was 39.5 days with a standard deviation of 9.2 for those with hyperglycemia (n = 18) and 16.5 days with a standard deviation of 2.5 for those without hyperglycemia (n = 29). At Iron Mountain the mean LOS was 21.5 days with a standard deviation of 3.3 for those with hyperglycemia (n = 10) and 13.6 days with a standard deviation of 1.2 for those without (n = 38). These differences were significant at p less than .01 using the 2-sample independent t-test. At Iron Mountain 5 of 38 (13%) of the patients with normoglycemia died during the hospital stay compared to 3 of 10 (30%) those with hyperglycemia. For Lexington the figures were 4 of 29 (13%) and 6 of 18 (33%) respectively. These differences were significant at p less than .05. Age did not have any significant effect on either mortality or length of stay. Hyperglycemia appears to be a significant predictor of a longer hospital course and increased mortality in elderly veterans hospitalized for pneumonia.

The age discrimination in employment act: A review of court decisions

Abstract: Over 600 federal court cases filed between 1970 and 1986 were reviewed in an attempt to discover the major themes and issues. Over all personnel decisions the employer was consistently favored (65%). Performance evidence was central to all cases reviewed. Subjective appraisals were often presented by management and were not considered suspect by the courts. Evidence of management's concern over the age of the workforce (e.g., economic costs and stereotypic beliefs) was also probative. Statistical evidence was presented in a majority of cases. However, inaccurate data and inappropriate comparisons negated its value. Most cases involved a termination or reduction in workforce decision (54%), but the most controversial area involved BFOQ's. A three-part sequential inquiry was proposed that would attempt to clear up these issues. Recent legal refinements may ease the plaintiff's burden in establishing a prima facie case of discrimination. Current techniques from the fields of industrial gerontology and industrial psychology may help clarify inconsistencies in court decisions.

Effects of chronic choline and lecithin on mouse hippocampal dendritic spine density

Abstract: Dendritic spines, which project from the dendrites of central neurons, are thought to contribute to the amount of contact area available for synaptic connections. The density of these spines has been found to correlate with learning and memory function, and there is a progressive decrease in dendritic spine density with aging. In addition, experimental animals given a choline-enriched diet have an increase in neocortical spine density compared to controls. In this study, the dendritic spine density of hippocampal pyramidal cells was examined in aged mice which had received life-long choline enriched, choline deficient or lecithin enriched diets. These treatments had no effect on hippocampal dendritic spine density compared to control. The results indicate that dietary supplementation may have different effects in different brain areas and that the relative increase in learning and memory function in aged animals given a choline or lecithin enriched diet is not due to an increase in hippocampal de...

Age and individual differences in immediate and delayed effectiveness of mnemonic instructions

Abstract: Young and older adults' performance was followed over three paired-associate trials, one on each of three lists All subjects received standard learning instructions prior to the first (baseline) list Mnemonic instructions, given prior to the second list to half the subjects, had significantly greater immediate benefit for the older adults relative to the benefit of practice alone However, there was a significant delayed effect of List 2 mnemonic instructions on List 3 performance for the young adults All subjects, both young and old, showed greater gains in performance level from List 1 to List 2 than from List 2 to List 3 The implications of these findings for a production deficiency explanation of age-related performance differences are discussed Scores on the WAIS-R Information subtest were significantly correlated with List 1 performance for the older adults, but not for the young Self-reported anxiety level was no different for young and old and was unrelated to baseline or to subsequ