Cross-sectional and longitudinal patterns of dedifferentiation in late-life cognitive and sensory function: the effects of age,ability, attrition,and occasion of measurement

The dedifferentiation hypothesis is examined with respect to age-group differences, ability-group differences, attrition-group differences, and time. Cognitive and sensory data were analyzed from individuals (n = 1,823) who completed a clinical assessment on at least 1 of 3 occasions of measurement in the Australian Longitudinal Study of Ageing. Inconsistent dedifferentiation effects were associated with low ability and early attrition from the study, but age-related dedifferentiation was not found. Longitudinal analyses confirmed the cross-sectional analyses. Even though instances of dedifferentiation were identified between pairs of sensory and cognitive variables, consistent patterns of dedifferentiation were not found. These results do not support the view that shared biological factors become increasingly important for explaining within-individual change in cognitive and sensory function in later life.     

A latent growth curve analysis of late-life sensory and cognitive function over 8 years: evidence for specific and common factors underlying change

Correlations among rates of change in sensory and cognitive functioning in adulthood were evaluated. Measures of Vision, Hearing, Memory, Speed and Verbal ability were obtained in 1992, 1994, and 2000 in the Australian Longitudinal Study of Aging (N = 2,087 at baseline). Data from 1,823 participants who undertook at least 1 clinical assessment were analyzed using latent growth curve models. A significant moderate-sized association between rates of change in Memory and Vision was found. This remained after statistically controlling for the effects of age, gender, education, self-rated health, medical conditions, and depressive symptoms. Rate of change in Hearing was weakly associated with rate of change in Memory. The results support a theory incorporating a major role for unique factors in addition to common factors underlying sensory and cognitive change in old age.     

Interventions for Midlife Smoking Cessation: A Literature Review

Midlife smoking continues to be a problem in Australia, with substantial personal, social, and financial costs. Yet the specific characteristics and needs of this group have been largely overlooked. Here we review the literature for the purposes of (1) profiling the characteristics of midlife smokers and (2) assessing the effectiveness of interventions for this group. This review shows midlife smokers differ from younger smokers in important ways: they underestimate the costs of smoking and overestimate the benefits, and are less confident in their ability to quit. The few studies investigating age‐tailored interventions have shown these to be effective in reducing midlife smoking. Still, research in this area is limited, with only one study conducted during the past decade that investigated smoking interventions for those in midlife. Clearly there is a need for smoking cessation interventions for midlife smokers that are tailored to the specific beliefs and needs of this unique group. Future research should focus on establishing the best methods for interventions for those individuals who are resistant to earlier interventions and still continue smoking into midlife. Interventions may benefit from incorporating recent evidence about the less obvious costs associated with midlife smoking, including later‐life neurological disease.     

Interrelationships among biological markers of aging, health, activity, acculturation, and cognitive performance in late adulthood

In this study a structural equation model of predictors of age differences in cognitive performance in late adulthood was developed. Biological markers of aging (vision, hearing, vibration sense, forced expiratory volume, and grip strength) were used as indicators of a latent variable called BioAge. A sample of 180 community-dwelling women aged 60 to 90 years was assessed. Results showed that BioAge explained all of the age-related variance in cognitive test performance. Physical health and physical activity had direct effects on BioAge. Measures of acculturation explained non-age-related variance in cognitive test performance. Some variables used as biomarkers also explained individual differences in measures of crystallized intelligence and perceptual speed. It is concluded that the association between biomarkers and cognition in old age is due to more than a common statistical association with age.     

The sounds of dominance.

A study was conducted to determine the effects of vocal cues on judgements of dominance in an interpersonal influence context. Physical measures of human vocal cues and participant ratings of dominance were obtained from videotapes of actors delivering short influence messages. After controlling for linguistic and visual content of messages, results indicated that mean amplitude and amplitude standard deviation were positively associated with dominance judgments, whereas speech rate was negatively associated with dominance judgments. An unexpected interaction revealed that mean fundamental frequency (F₀) was positively associated with dominance judgments for male speakers but not significantly associated with dominance judgments for female speakers. F₀ standard deviation was not significantly associated with dominance judgments. Results support the conclusion that dominance judgments are inferred from multiple sources of information and that some vocal markers of dominance are more influential than others.     

The coherence of cohesion in the later Leibniz

This paper expounds and critically assesses G. W. Leibniz’s mature theory of the cohesion of material bodies. Leibniz’s later view of cohesion was forged in polemical engagement with the views of John Locke and the Dutch natural philosopher Nicolaas Hartsoeker and it is in Leibniz’s response to Locke in his New Essays on Human Understanding, and especially his correspondence with Hartsoeker, that the theory is revealed. After setting out Locke’s theory of solidity and cohesion, the paper examines Leibniz’s response to Locke in the New Essays. It then proceeds to the mechanical theory of conspiring motions developed in the Hartsoeker correspondence. The final section of the paper poses three problems for Leibniz’s theory – explanatory, empirical, and conceptual.     

The effect of perceived control on self-reported cardiovascular disease incidence across adulthood and old age

Objective: To examine whether rates of change in perceived control are predictive of cardiovascular disease (CVD) incidence across adulthood and old age.

Design: We used the PATH Through Life Project (n = 7103, M = 40, SD = 16; 52% women), a longitudinal panel survey that encompasses three cohorts at Time 1, ages 20–24, 40–44 and 60–64, who have been assessed three times at four-year intervals.

Method: We examined whether rates of change in perceived control were associated with CVD incidence over 8 years of time, over and above that of baseline levels of perceived control and known risk factors for CVD.

Main Outcome Measures: Self-reported CVD incidence.

Results: Increases in perceived control over time were associated with decreased likelihood of 8-year incidence of CVD and these effects were independent of socio-demographics, covariates and baseline levels of perceived control. The effects were consistent across young adulthood, midlife and old age and for men and women.

Conclusions: Findings demonstrate the importance of changes in perceived control as a predictor of CVD incidence across adulthood and old age. We suggest future research using mediation analysis to test reverse causality and mechanisms underlying the effects of perceived control on CVD incidence.     

A Longitudinal Investigation of Perceived Control and Cognitive Performance in Young,Midlife and Older Adults

ABSTRACT

Longitudinal associations between generalized control beliefs (one's perceived capacity to influence events) and cognitive test performance were examined in a population-based sample of young, midlife and older adults. Participants provided measures of perceived control, self-assessed health, education and depression and anxiety symptoms, and completed cognitive tests at two assessments, 4 years apart. For each age group, baseline (between-person) control was positively related to performance on tests of memory (immediate recall and digits backwards), speed (Symbol Digit Modalities Test and choice reaction time) and verbal intelligence (Spot-the-Word). Interaction effects indicated stronger associations of between-person control beliefs with indices of speed for the older age group relative to the younger groups. Within-person changes in control were not significantly associated with changes in cognitive test performance over the study interval. Implications of the findings for self-efficacy based interventions designed to promote cognitive functioning are discussed.     

Differentiating insight from non-insight problems

This study aimed to investigate whether a range of tasks that have been generally classed as requiring insight form an empirically separable group of tasks distinct from tasks generally classed as non-insight. In this study, 24 insight tasks, 10 non-insight tasks, and tests of individual differences in cognitive abilities and working memory were administered to 60 participants. Cluster analysis of the problem-solving tasks indicated that the presumed insight problems did tend to cluster with other presumed insight problems, and similarly the presumed non-insight problems tended to cluster with other presumed non-insight tasks. Performance on presumed insight problems was particularly linked to measures of ideational flexibility with a different pattern of results for the non-insight tasks. Spatial insight problems were linked to spatial flexibility and verbal insight tasks were linked to vocabulary scores. The results are discussed in relation to recent developments of dual process theories of thinking.