Awareness of age-related change: Individual differences, intra-individual variability, and implications for self-regulation and well-being in middle and older adulthood

Author: Bethany Wilton-Harding

  • Thesis download: available for open access on 14 Jan 2025.

Wilton-Harding, Bethany, 2022 Awareness of age-related change: Individual differences, intra-individual variability, and implications for self-regulation and well-being in middle and older adulthood, Flinders University, College of Education, Psychology and Social Work

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Development at all points in life consists of a balance of gains and losses. Furthermore, developmental changes in different life domains vary substantially both between individuals and within individuals over time. The multidirectionality and multidimensionality of development has captured increasing interest in gerontological research in the past decade. The construct of awareness of age-related change (AARC) captures both positive (AARC-gains) and negative (AARC-losses) components of subjective ageing across different behavioural domains. Overall, previous research has found that adaptive outcomes are associated with higher AARC-gains, and lower AARC-losses. The aim of the current thesis is to expand on previous research by examining how AARC-gains, AARC-losses and the interplay between the two may relate to adaptive outcomes of goal adjustment and well-being in middle and older-adulthood.

The first cross-sectional study examined the role of AARC-gains, AARC-losses and their interaction in the prediction of goal adjustment strategies. Results showed that greater goal adjustment capacities were associated with higher AARC-gains, and lower AARC-losses. Furthermore, AARC-gains was shown to buffer the association between AARC-losses and goal adjustment. Additionally, relationships between AARC and processes of goal adjustment were shown to be mediated by the subjective sense of future lifetime.

The second study focused on between-person differences in AARC-gains, AARC-losses and their interaction in the prediction of both between-person differences in psychological well-being, and longitudinal change in well-being over time. Results showed that neither AARC-gains, AARC-losses, nor their interaction predicted reliable change in well-being outcomes over 12 months. However, at the between-person level, greater levels of well-being were associated with higher AARC-gains and lower AARC-losses. Additionally, the relationship between AARC-losses and well-being was buffered by AARC-gains.

The third study aimed to test the proposition that the relationship between AARC and well-being is mediated by self-regulation of goals. Longitudinal mediation results showed that the expected temporal order of associations (T1 AARC > T2 goal re-engagement > T3 well-being) was not evident. However, results indicate that AARC-gains may mediate longitudinal relationships between well-being and goal re-engagement. These findings, together with previous theoretical and empirical research suggest that further investigation using varying timescales may be needed to gain greater understanding of relationships between AARC, goal re-engagement, and well-being.

The final study moved beyond viewing AARC as a trait-level construct and investigated whether daily AARC may have implications for reactivity to daily stress. Analysis indicated that on days when AARC-gains was higher-than-usual, participants showed less affective reactivity to daily stressors (represented by lower negative affect). Furthermore, on days when AARC-losses was higher-than-usual, participants showed increased reactivity to daily stressors (represented by higher negative affect). However, interactions of daily stress with within-person AARC were not statistically reliable when controlling for between-person stress × within-person AARC, indicating that both between- and within-person variance captured by assessments of daily stress were implicated in the AARC moderation effects.

Taken together, findings from the studies in the current thesis extend knowledge regarding AARC and implications for adaptive ageing. The findings support that AARC has implications for goal adjustment and well-being and show that (1) the impact of AARC-losses on adaptive outcomes may be buffered by AARC-gains, (2) well-being, AARC, and goal adjustment may inform one another over time, and (3) daily AARC has implications for well-being and stress reactivity at the daily level. Together, these findings may inform future research directions including potential intervention programs which aim to promote positive self-perceptions of ageing which may in turn facilitate greater adaptation in middle- and older-adulthood.

Keywords: awareness of ageing, subjective aging, perceptions of ageing, self-regulation, self-determination

Subject: Psychology thesis

Thesis type: Doctor of Philosophy
Completed: 2022
School: College of Education, Psychology and Social Work
Supervisor: Associate Professor Tim Windsor