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Highly skilled adolescent (15-19 years), young (25-35 years), middle-aged (50-57 years), and older (58-73 years) miniature golf players were examined in training and competitive conditions. Number of shots, heart rate, ratings of anxiety, and concentration time were registered. IN addition, two attentional subscales from the Test of Attentional and Interpersonal Style (TAIS) inventory (Nideffer, 1976) were administered. Results indicated (a) parallel increases of heart rate and rated anxiety in competition for all age groups, (b) improvement of motor performance in competition for adolescent and young-adult players, and deterioration of motor performance in competition for middle-aged and older players, and (c) increased concentration time for the two younger samples, and decreased concentration time for the two older samples in competition. As well, the TAIS data indicated greater self-perceived external and internal distractability in the two older, compared to the two younger samples. This age-related vulnerability to distractions was shown to partly mediate age differences in competitive motor performance. The overall pattern of outcome is discussed relative to the view that the adult aging process is associated with a deficit in the ability to handle situations of high arousal due to age-related deficits in a variety of basic cognitive capacities.

In previous studies, male rats given access to voluntary running wheels showed improved survival. Because the male runners did not increase food intake, it was not clear whether their improvement in average longevity was due to decreased availability of energy for cell proliferation and growth or to another effect of exercise. In this study, female rats, which increase their food intake in response to wheel running, were used to determine whether exercise can increase longevity when availability of energy for cell proliferation and growth is not decreased. At age 5 mo, the female voluntary wheel runners were running 9173 +/- 3640 m/day (mean +/- SD); running distance declined to 965 +/- 483 m/d by age 34 mo. From 5 mo to 10 mo of age, the runners ate approximately 37% more than the sedentary rats. Thereafter, the runners ate approximately 20% more. The runners and sedentary rats attained similar peak body weights. However, the runners gained weight more rapidly, attaining steady state by 11 mo; the sedentary rats' weights did not plateau until approximately 15 mo. The runners had a significant prolongation of average longevity without an increase in maximal life span. The sedentary rats' average age at death was 924 +/- 155 days (mean +/- SD; range, 619-1263 d) compared to 1009 +/- 132 days (range, 693-1259 d) for the runners, p < .001. These results show that exercise improves average longevity of rats independent of decreased availability of energy for cell proliferation and growth. They also provide evidence that an increase in food intake is not harmful when balanced by an increase in energy expenditure.

A longitudinal study of plasma glucose and insulin concentrations in ad libitum fed and dietary restricted male F344 rats was carried out. The life span diurnal pattern of plasma glucose concentration was such that through most of the day dietary restricted rats have significantly lower plasma glucose levels than ad libitum fed rats. Throughout the life span, dietary restricted rats maintain mean 24-hour plasma glucose concentrations about 15% below those of ad libitum fed rats. Plasma insulin levels are maintained in dietary restricted rats at about 50% of the levels in ad libitum fed rats. Although plasma glucose and insulin levels are lower, dietary restricted rats use glucose fuel at the same rate per unit of metabolic mass per day as rats fed ad libitum. While these findings are consistent with the glycation hypothesis of aging and with our hypothesis that dietary restriction retards the aging processes by altering the characteristics of fuel use, they do not establish the validity of either. It is possible that this effect of dietary restriction on carbohydrate metabolism plays no role in its antiaging action. Further studies are required to define the role of these altered characteristics of carbohydrate metabolism in the aging processes.

The accumulation of lipofuscin, an important phenomenon during aging, suggests that the sexual maturity (puberty) of mammals is a starting point of the aging process. The rate of cardiac lipofuscin accumulation was not correlated linearly with maximum life span of mammals, but the correlation was a power function of the maximum life span. The rate of lipofuscin accumulation statistically correlated with the specific metabolic rate, and inversely correlated with the brain weight of mammals. The first appearance of lipofuscin showed a good correlation with the brain weight. However, the slope of the line was different between primates and domestic and laboratory animals. From these results, it is suggested that the accumulation of cardiac lipofuscin is dependent on the specific metabolic rate of mammals.

We found significant and similar associations of facial recognition memory performance with age using two different methodologies: signal detection (SD) and delayed nonmatching-to-sample (DNM). These data demonstrate that previously reported associations between age and facial recognition memory performance were not specific to method of assessment, and that significant declines are seen as early as 50 years of age.

Different cognitive functioning, social, and personality changes appear to occur systematically during the adult life span. This article synthesizes research on life span changes in order to develop age-specific models of shopping behavior. The models are tested within a naturalistic field study of shoppers.

The Glucocorticoid Cascade Hypothesis of Aging and the hypothesis that food restriction retards the aging processes by preventing the development with age of hyperadrenocorticism were investigated. A longitudinal life span study of the daily concentration pattern of plasma corticosterone was conducted in male Fischer 344 rats fed ad libitum or restricted to 60% of the mean food intake of ad libitum fed rats. In another group of ad libitum fed and food-restricted rats, the influence of age on the response of plasma corticosterone levels to restraint stress was measured as was the time course of the return of plasma corticosterone to basal levels following the stress. The findings do not support the hypothesis that food restriction retards the aging processes by preventing the development of hyperadrenocorticism with advancing age. They also indicate that the Glucocorticoid Cascade Hypothesis does not describe a major aspect of the aging processes. Rather, the results suggest the possibility that a lifetime of daily periods of mild hyperadrenocorticism may, if anything, retard the aging processes.

Biomarkers of aging are needed to evaluate proposed treatments to retard aging rates. At present, the only validated biomarker of aging is maximum life span, which remains impractical for human use. Identification of other biomarkers awaits development of a method of biomarker validation. This paper outlines an approach for this purpose intended for selecting biomarkers usable in humans. Prospective biomarkers are validated and weighted according to their correlation with interventions that, in healthy individuals, influence life span, namely mortality risk factors. A general mathematical method is presented for combining biomarker scores into an index of aging rate. This method addresses problems encountered with the traditional (multiple regression) method of calculating biological age and develops an index termed standardized biological age, SBA. In applying the method to 2,462 office workers, SBA, based on 12 physiological tests under investigation as biomarkers of aging, was found to depend on most of 17 surveyed dietary, exercise, life style, and geographical risk factors for mortality or health, suggesting that many risk factors predict rates of common functional declines with age. The 12 candidate biomarkers of aging in this study differed widely in validity according to the criterion employed. The approach holds promise for assembling an experimentally useful battery of biomarkers of aging.

To investigate effects of dietary caloric restriction (DR) combined with antioxidant feeding, long-lived hybrid mice were divided into four dietary groups at weaning, and followed until natural death. Groups "C" and "R" received control (97 kcal/wk) and restricted (56 kcal/wk) diets respectively. Groups "C+ alpha ox" and "R+ alpha ox" received C or R diets supplemented with an antioxidant mixture (2-mercaptoethylamine plus ethoxyquin). R mice (mean life span 41 months) significantly outlived the other three groups (mean life span 30-34 months). Hepatic degeneration and increased hepatoma in the R+ alpha ox group suggested unusual hepatotoxicity of this regimen. Antioxidants had little effect on splenic cell mitogen response in similarly fed mice sacrificed at 12-15 months. Gompertz analysis suggests that the beneficial effect of DR may be due to reductions in initial vulnerability or rate-of-aging parameters, or both, and that the relative influence of each factor may vary with animal strain and DR protocol used.

Longitudinal studies have contributed much to the understanding of aging. Traditionally, age-specific changes in physiological functioning are inferred from studies in which persons with disease processes believed to be relevant to the function in question are excluded from the results. The main theme of this review is that, in the future, studies of aging must better attempt to capture the interplay between disease and aging processes. A variety of research results, mostly from the Baltimore Longitudinal Study of Aging, are used to support this argument. Topics covered include: the role of longitudinal studies in aging research; the complexity of the aging process; the significance of cohort and secular changes for understanding both aging and disease processes; age changes over the adult life span in the significance of risk factors for disease; and age-related increases in morbidity in a longevous group of men.

Intestinal malabsorption of nutrients may be a critical factor in aging. For this reason, we investigated the nutrient absorption in mice of different ages of the life span, representing growth (3 mo), young adult (12 mo), mature (24 mo), old (30 mo), and very old (33-36 mo) periods. The everted sac technique was used to study the transepithelial transport of D-glucose, 3-O-methyl-D-glucose (3MG), and L-tyrosine. There was a 32% increase in the rate of D-glucose transepithelial transport during growth followed by a 55% decrease in the old mouse, and the same pattern occurred with 3MG, a nonmetabolized glucose derivative. However, L-tyrosine transepithelial transport was not impaired until the mouse reached the very old, 33-36 mo period. Also, the rate of D-glucose metabolism measured by lactate production in the very old mouse was only 45% of the mature mouse value. In addition, these transepithelial transport changes were accompanied by decreases in the number and the height of villi. The results indicate that intestinal transepithelial transport and the surface area for absorption decrease in aging.

To develop a battery of innocuous tests measuring individual differences in the rate of biological aging, longitudinal data were gathered on 28 biochemical, physiological, and morphological characteristics of 40 adult female pigtailed macaques. The change in each variable over time, i.e., the beta coefficient of linear regression, was calculated for each animal, and a matrix of correlations among the variables was constructed. Eight variables correlated well with the first principal component of the matrix. These variables (rate of fingernail growth, blood lymphocytes, mean corpuscular hemoglobin, immunoglobulin A, and serum sodium, chloride, total protein, and creatinine) represented the best subset of the potential biomarkers analyzed to produce an index covering a range of morphologic and functional systems that change with age. A similar set representing a wider range of systems and measured over a larger fraction of the life span should provide a valid index of an individual's rate of biological aging.

The heritability of human longevity was investigated in a sample of 218 pairs of monozygotic (MZ) and 382 pairs of like-sex dizygotic (DZ) Danish twin pairs born 1870-1880. Twin similarity for age at death was significant for MZ twins but nonsignificant for DZ twins. The heritability (h2) of life span estimated from the best-fitting biometrical model was statistically significant but moderate in magnitude (h2 = .333 ± .058). Heritability of longevity did not vary by gender, and the pattern of twin resemblance was more consistent with nonadditive as compared to additive genetic effects. In addition, evidence for a genetic association between premature and senescent deaths was observed. Although environmental factors accounted for a majority of the variance in life span, the relevant environmental factors appeared to be those that create differences rather than similarities among reared- together relatives. Findings are discussed in terms of their relevance for understanding the inheritance and evolution of human life span.

An odor description task was used to explore age-related change in odor perception based on 1.19 million U.S. and Canadian respondents (ages 10-90 years) to the National Geographic Smell Survey. Respondents sampled six microencapsulated odorants and selected 1 of 11 descriptors to characterize each smell. Four odors were characterized by strong consensus endorsement of a single descriptor. This consensus weakened with advancing age, and nonmodal descriptors were endorsed more frequently. Nonmodal responses were neither randomly selected, nor systematically biased across odors. Rather, they showed odor-specific patterns of change. Together, these results suggest a marked change in odor categorization across the life span. Odor descriptor profiles were used to generate age-specific multidimensional scaling maps. Stimulus configurations were stable from the third through fifth decades. Those from the sixth through ninth decades showed major displacements for two odors, and suggest that the sweet dimension of odor quality may be particularly variable with maturation.

Insulin-like growth factor-1 (IGF-1) decreases with age in many species and appears to have an important role in the age-related decline in capacity for protein synthesis with age. The goals of these studies were to determine whether (a) ad libitum fed mice demonstrate age-related decreases in IGF-1, (b) the relationship between IGF-1 and age-related changes in protein synthetic capacity in ad libitum fed animals, and (c) whether moderate dietary restriction (which increases both life span and protein synthetic capacity) delays age-related changes in protein synthesis and plasma IGF-1. These studies indicate that (a) in ad libitum fed animals, plasma IGF-1 decreases with age between 10 and 15 months and moderate dietary restriction decreases plasma IGF-1 in young but not older animals, and (b) the temporal changes in protein synthesis are tissue specific; moderate dietary restriction either increases or prevents the age-related decline in tissue protein synthesis. Results suggest that in normal aging, decreases in IGF-1 are associated with the decline in protein synthesis but that other regulatory mechanisms appear to have an important role in this process. Dietary restriction decreases plasma IGF-1 in young animals and either increases protein synthesis or prevents the age-related decline in protein synthesis, suggesting that the effects of dietary restriction are not mediated via increases in plasma IGF-1.

SAM-P/8 (P/8if) mice, trained on aversive and appetitive training tasks, showed age-related impairment of learning on more difficult tasks. Using aversive training tasks, acquisition of step-down passive avoidance did not differ between 4- and 12-month-old mice. T-maze footshock avoidance acquisition detected impairment from 9 to 12 months of age. On the appetitive tasks, 12-month-old mice required significantly more trails than 4-month-old mice to learn to press a lever for milk reinforcement or to learn a specific sequence of 10 black-white, left-right discriminations. However, learning a simple black-white discrimination in the same 10-unit maze did not discriminate between the performance of 4- and 12-month-old mice. A lack of age-related changes in food, water, and milk consumption suggests that changes in motivation do not account for the decline in learning in older P/8if mice. The results suggest an early onset of impaired learning relative to the 17.2-month median life span of the P/8if mice.

Two studies were conducted to assess motivational aspects of the self by measuring hoped-for and feared possible selves among a sample of older adults and college students. It was predicted that health-related possible selves would be predominant among older adults, but not college students, and that self-regulatory aspects of possible selves would be related to perceived health. Data were collected through interviews and questionnaires. Older adults were significantly more likely to have possible selves in the realm of health than were college students. Regression analyses with the older sample indicate that outcome expectancy for a hoped-for self was positively related to perceived health, whereas amount of time spent thinking about a hoped-for possible self was negatively related to perceived health. However, these relationships were not significant when evaluated in relation to a feared possible self, indicating that there may be differences in the way self-regulatory processes operate in service of positive, as opposed to negative, goals for the self. Results are discussed with reference to theoretical models of self-efficacy and motivation over the life span.

Lymphocyte subsets from four groups of Lobund-Wistar (L-W) rats were quantitated to determine the influence of diet restriction (DR) and exposure to environmental antigens on the development of these cells. The following effects were found from 6 to 30 months of age: The number of Ts/c and Ts cells were higher in germ-free (GF) vs conventional (CV) rats, whereas B-cell numbers were lower. W3/13 T cells, Ts, and NK cell numbers were higher in DR vs full-fed rats, whereas B-cell numbers were lower. OX19 and W3/13 T cell numbers decreased from 6 months to 30 months in each group, whereas NK cell numbers increased. Also, OX6+ B cell numbers increased with age, and Ts/c numbers decreased. These data may reflect a relationship between enhanced T-cell function and the extended life span and lower tumor incidence observed in DR L-W rats.

The quantity and type of microsomal cytochrome P-450 was determined in early passage cultured fibroblasts from six mammalian species of widely differing life spans. The proportion of cytochrome P-450 and P448 varied considerably among species, with the shorter-lived species having a preponderance of cytochrome P-448. There was a good inverse correlation between potential species life span and the specific cytochrome P-448 content of cultured fibroblasts.

Extensive investigations on the metabolism of animal lenses over the life span indicate various changes that, regarded collectively, suggest a decrease in metabolic energy. A factor analytic interpretation and discussion of these results indicate that enzyme modifications might be one of the fundamental causes of the age-related changes in lens metabolism. Detailed investigations on the kinetic and physicochemical properties of certain enzymes of the carbohydrate breakdown in lenses of different ages verify this assumption. Since the changes observed are found mostly in the lens nucleus protein neosynthesis no longer takes place, posttranslational modifications appear to be responsible.

Measures of life-span were obtained for male and female A/J, BALB/cJ, C57BL/6J, and DBA/2J inbred mouse strains and the six possible hybrid combinations (N equals 500, 10 groups, 25 male and 25 female per group). C57BL/6J mice were long lived, while A/J, BALB/cJ and DBA/2J mice were short lived, with the exception of female BALB/cJ mice, which lived as long as C57BL/6J mice. Female BALB/cJ and two female hybrid mouse groups with a BALB/cJ parent lived longer than males, but significant sex differences were not obtained for other groups. In general, the mode of inheritance of longevity was overdominant. For a second study (N equals 400) of the longevity of A/J and C57BL/6J strains and F1 and F2 hybrids it was estimated that one genetic factor was associated with longevity and the coefficient of genetic determination for longevity was estimated as between .48 and .79.

A group of 1,052 C57BL/6J mice (296 males and 756 females) was kept under well-defined, clean laboratory conditions from the age of 6 weeks until natural death. The survival curves of males and females (computer-produced 3, 4, and 5 parameter curves, Gompertz curve histogram) were established and shown to follow a logistic function. The average life-span amounted to 878 plus or minus 10 days for males and 794 plus or minus 6 days for females. These values distinctly exceed comparable values given in the literature. They are attributed to favorable conditions of animal care and to supposed alterations in genetic background. A genetic drift in sex-dependent mean survival time occurred in the genetically unstable C57BL/6J strain between 1966 and 1970. Before this drift, the males died sooner; after it, they lived longer.

Laterality of hand, foot, eye, and ear was measured in a sample of 1964 subjects, ranging in age from 8 to 100 years. Age trends were found, with hand, foot, and eye preference becoming more right-sided and ear preference becoming more left-sided with increasing age. Sex differences emerged in foot, eye, and ear preference but these did not systematically interact with the age variable. Several causal mechanisms are proposed but none can fully explain either the direction or the magnitude of the observed age changes. Thus, these data are most consistent with the view that the study of sidedness in humans should proceed with a consideration of a complex of underlying factors and individual difference variables.

The aims of this research were (a) to compare food restriction initiated in adult life of male Fischer 344 rats with that limited to early life or involving most of the life span on physical, metabolic, and longevity characteristics and (b) to study a similar level of protein restriction without caloric restriction on these characteristics. Food restriction (60% of the ad libitum intake) initiated at 6 months of age markedly increased life span as did a similar restriction started at 6 weeks of age, but food restriction limited to early life (6 weeks to 6 months of age) and protein restriction caused only a small increase in longevity. Food restriction does not act by reducing the intake of calories or other nutrient per gram of body mass, a finding not in accord with classic views. A progressive decrease in spontaneous locomotive activity with age occurred in ad libitum fed but not restricted rats.

Male Fischer 344 rats were either fed ad libitum (Group A) or 60% of the ad libitum intake (Group R) starting at 6 weeks of age; the latter is a life prolonging food restriction. Total adipose mass increased with increasing age in both Group A and Group R rats until about 70% of the life span after which it declined. The results indicate that the lower adipose mass of the Group R rats is probably not related to life prolongation. Adipocyte hypertrophy is involved in growth of the epididymal and perirenal depots in adult Group R rats and is the sole basis of epididymal depot growth in adult Group A rats. Increasing adipocyte number is the sole basis of perirenal depot growth in adult Group A rats and is involved in the growth of both depots in adult Group R rats. Decreasing adipose mass during senescence involves decreasing mean adipocyte volume but not a decrease in the adipocyte number.

Hormones can promote or inhibit aging depending on the experimental conditions employed. The aging effects of hormones are demonstrated by reducing hormone secretion by hypophysectomy or chronic underfeeding in young or mature rats. These result in depressing whole body metabolism, growth, body temperature and blood glucose levels, heart rate and vital capacity, gene expression, etc., but delaying aging of tissues, suppressing development of pathology and tumors, and, in underfed rats, prolonging life span. The anti-aging effects of hormones are demonstrated by elevating hormone levels in old rats whose hormones have declined as a result of dysfunctions that develop in the neuroendocrine system with age. An increase of hormones in these rats promotes gene expression, elevates protein synthesis, and enhances metabolism, growth, and function of stimulated organs and tissues.

Two experiments were conducted in order to discover (a) the expressed attitudes of young adults about the intellectual abilities of seven target groups ranging in age from infant to elderly, and (b) if and in what manner young adults differentially explain the rules of a simple game to these same target groups. In Experiment I, questionnaires requiring the attribution of intellectual capabilities of infants, preschoolers, preadolescents, adolescents, and young and middle-aged, and elderly adults were completed by 243 subjects. Intellectual ability was seen as increasing with age until old age. The elderly were consistently perceived as less competent than both young and middle-aged adults. The result of Experiment II, in which 60 subjects participated, suggested that young adults modify the complexity of their communications to different aged listeners in accordance with their expressed perceptions of the intellectual attributes of their auditors.

The lysosome hypothesis of aging predicts that membrane stabilizers will extend life-span. Stabilizers containing the dimethylaminoethanol moiety (DMAE) have been reported to extend the life-span of drosophila and mice. We tested the prediction in Japanese quail (N = 15) by administering DMAE bitartrate (18.4 mg/kg/day) in the drinking water for 69 weeks, starting at 195 weeks of age. A matched control group (N = 14) received tartaric acid (4.0 mg/kg/day) in the water. Contrary to the prediction, the DMAE-treated group has a shorter life-span after start of treatment (49 weeks) than the controls (69 weeks). No significant differences between the groups were observed in body weight or daily fluid intake. Three behavioral studies were carried out on survivors at 243-249 weeks of age, namely; activity response to light-flash; sexual mounting response to a female quail; and classical conditioning of the heart rate. Aged quail differed from young-adults in changes in motor activity in response to light flashes. Aged quail appeared less responsive initially to reinforced conditioning trials and demonstrated extinction when light flash was not followed by electric shock. There were no detectable differences in latency to mount or in basal heart rate, either as a function of age or as a function of DMAE treatment.

Groups of inbred A/J and C57BL/6J mice and hybrid F1 mice were fed low dietary protein (4% casein) or normal dietary protein (26% casein), with 50 mice in each of the six subgroups. For individual mice within subgroups, growth rate was negatively related to longevity; i.e., the slower the rate of growth the greater the life-span. Between subgroups, the longer the mean growth duration, the longer the mean lifespan. Positive relationships were obtained within subgroups for peak body weight and longevity. It is concluded that, for mice, slowing the rate of growth and increasing growth duration results in a significant increase in the life-span, and the life-span increment is not related to high peak body weight since high body weight, per se, was not correlated with life-span.

This report is based on previous data that showed that Turkish hamsters that hibernated lived longer than nonhibernating controls. Fluorescent microscopy was used to measure the lipofuscin content of brain and heart of hamsters that hibernated for various fractions of their lives. According to regression data the 13 animals that hibernated 11 to 37% of their lives had a slower accumulation of lipofuscin than 11 animals that hibernated 0 to 7% of their lives. It was calculated that the total amount of pigment accumulated during a life span was the same in both groups, in spite of the longer life of the hibernators.

Butylated hydroxytoluene (BHT) was given in the feed to determine its effect on life span in genetically well-defined, barrier-derived BALB/c mice. Both sexes received 0.75% BHT for three different treatment periods: (A) 8 to 11 weeks of age; (B) for life, beginning at 11 weeks; (C) for life, beginning at 8 weeks of age. The control group (D) was untreated. All BHT treatment groups had mean survival times which exceeded that of controls. The order of survival was B greater than C greater than A greater than D (Males: 890, 832, 726, 684 days; Females: 875, 798, 759, 701 days). Most of the increases in mean survival time were related to a reduction in early deaths (350--600 days) in BHT-treated mice. The reason for the life-lengthening effect on BHT was not identified, but it may relate to alterations in specific disease incidences.

Conflicting results have been reported for the lifetime distribution of personal memories. To resolve the discrepancy, two age groups were asked to respond to cue words by supplying event associations, and to date the remembered events using either the standard or a serial procedure. Memory retrieval times, dating times, and the frequencies of elicited memories, were compared across the four quarters of the life span. The 70-year-olds took twice as long to respond, and twice as long to supply dates, as the 20-year-olds. Age interacted with period of life, in dating time, but not with the dating method on any measure. The serial dating method halved the time required by the standard method but, as predicted, distorted the lifetime frequency pattern. With serial dating, earlier memories were more rapidly dated and more numerous than with the standard procedure. The effects are ascribed to the activation of temporal markers in both age groups.

Male Wistar rats were maintained on four dietary regimens: fed ad libitum throughout life (A); fed intermittently either during the first year of life and ad libitum thereafter (RA) or vice versa (AR); and fed intermittently throughout life (R). Low body weights, low amounts of body components (protein, fat, moisture, and ash), and long life spans were observed in R. AR and RA lost or gained body weight, respectively, after dietary transfer and lived longer than A. Maximum body weight and the age at which it was attained were correlated positively with life span in A. Predicted mature body weight was correlated negatively with life span in R. RA and AR differed in growth and body composition, but their life spans were similar and intermediate to those of A and R. Increases in life span were obtained by intermittent feeding during all or part of the life span, but growth and body composition data did not consistently explain the mechanism of this effect.