Age Differences Across Adulthood in Interpretations of Situations and Situation-Behaviour Contingencies for Big Five States.

Prospective memory (PM) is the ability to remember and perform intended actions at the appropriate point in the future. PM is a cognitive ability that is vital to many aspects of daily functioning, and it is particularly important for older adults who wish to maintain functional independence. The overall aim of this thesis was to investigate factors that potentially contribute to the age-PM paradox. The age-PM paradox refers to the contrasting age effects on PM performance with age-related deficits observed on laboratory tasks, but no age differences or even age-related benefits observed on naturalistic tasks. Several proposed factors that possibly contribute to the age-PM paradox were examined in two tangential studies. Firstly, a descriptive study of self-directed PM tasks in daily life was conducted. The study examined how the context of PM task completion in the real world might vary between young and older adults, as such differences may contribute to age differences in naturalistic PM performance. To improve upon previous naturalistic studies, the study employed an experience-sampling method to capture PM successes and failures throughout the day. Contrary to popular belief, the findings suggest that dissimilarities in the demands of everyday life and the usage of external reminders, such as diaries, cannot explain the improved naturalistic PM performance of older adults. However, older adults were found to regard their PM tasks as important more often than young adults. Older adults also rehearsed their PM intentions more frequently than young adults. Thus, it is possible that the age benefit observed in naturalistic settings is related to older adults’ motivation and their ability to plan and rehearse their PM tasks within their own environment. Relatively few instances of PM failures were reported by both age groups. Further evidence suggests that participants retrieved their PM intentions through both spontaneous retrieval and strategic monitoring processes, which provides support for the multiprocess framework of PM. The second study rigorously examined whether the comparison of inherently dissimilar tasks could be contributing to the age-PM paradox. Laboratory PM tasks are predominantly event-based tasks, while naturalistic PM tasks are typically time-based, occurring at a set time of day. To address the lack of task comparability across settings, novel naturalistic PM measures were developed to objectively assess PM performance on three types of tasks: event-based, scheduled time-based (typical of prior naturalistic studies), and time-check tasks (typical of prior laboratory studies). The study is the first investigation of age differences in laboratory and naturalistic settings on all three types of PM tasks using the same participant sample in both settings. Laboratory PM performance was assessed using a computerised version of Virtual Week, which simulates activities of daily life in a board game format. Naturalistic PM performance was assessed using smartphones and an application developed specifically for this thesis. In the laboratory, age-related deficits were observed on all three task types. However, in the naturalistic setting, older adults performed better than young adults on scheduled time-based tasks, performed just as well as the young adults on event-based tasks, and performed equally poorly on time-check tasks. The findings suggest that older adults demonstrate improved PM performance in everyday life when the PM tasks possess an event-like quality, which allows for further environmental support for successful task completion. Regardless of the setting, older adults consistently exhibited poor performance on time-check tasks. This finding suggests that older adults’ PM performance suffers when the PM tasks are particularly demanding and rely heavily on effortful monitoring processes for intention retrieval. Overall, the current research suggests that the age-PM paradox cannot be completely explained by contextual differences surrounding naturalistic PM performance or by the lack of task comparability across settings in the existing literature. However, given the substantial improvement in older adults’ naturalistic performance on scheduled time-based tasks, but not on time-check tasks, this thesis highlights the importance of this relatively rare time-based task distinction when considering the age-PM paradox. Taken together, the studies indicate that older adults’ naturalistic PM performance benefits from explicit cues, environmental support, and the ability to plan and rehearse PM intentions.

Speechreading and Aging

Introduction: The use of shared automated vehicles (SAVs) should lead to several societal and individual benefits, including reduced greenhouse gas emissions, reduced traffic, and improved mobility for persons who cannot safely drive themselves. We define SAVs as on-demand, fully automated vehicles in which passengers are paired with other riders traveling along a similar route. Previous research has shown that younger adults are more likely to report using conventional ridesharing services and are more accepting of new technologies including automated vehicles (AVs). However, older adults, particularly those who may be close to retiring from driving, stand to greatly benefit from SAV services. In order for SAVs to deliver on their aforementioned benefits, they must be viewed favorably and utilized. We sought to investigate how short educational and/or experiential videos might impact younger, middle-aged, and older adult respondents’ anticipated acceptance and attitudes toward SAVs. Knowing what types of introductory experiences improve different age groups’ perceptions of SAVs will be beneficial for tailoring campaigns aiming to promote SAV usage. Methods: We deployed an online survey using the platform Prolific for middle-aged and older respondents, and our departmental participant pool for younger adults, collecting 585 total responses that resulted in 448 valid responses. Respondents answered questions regarding their demographic attributes, their ridesharing history, preconceptions of technology, as well as their anticipated acceptance attitudes towards SAVs as measured by the dimensions of the Automated Vehicle User Perception Survey (AVUPS). After this, respondents were randomly assigned to an intervention condition where they either watched 1) an educational video about how SAVs work and their potential benefits, 2) an experiential video showing a AV navigating traffic, 3) both the experiential and educational videos, or 4) a control video explaining how ridesharing works. Anticipated acceptance attitudes towards SAVs were measured again after this intervention and difference scores calculated to investigate the effect of the intervention conditions. Prolific respondents were paid at a rate of $9.50/hour and younger adults received course credit. Results: Controlling for preconceptions of technology and ridesharing experience, a MANOVA was run on the difference scores of the dimensions of the AVUPS (intention to use, trust/reliability, perceived usefulness (PU), perceived ease of use (PEOU), safety, control/driving-efficacy, cost, authority, media, and social influence). Both older and middle-aged adults expressed significantly greater increases in PEOU and PU of SAVs than younger adults. We also observed an interaction between age and condition for both PU and PEOU. For PU, older adults’ difference scores were found to be significantly greater than younger adults’ for the control video condition. With PEOU, older adults’ difference scores were significantly greater than both younger adults’ for the control video condition, and middle-aged adults had greater difference scores for the educational-only video condition than younger or older adults. Discussion: The increases in PU observed for older adults in the control condition suggests that educating them on how to use currently available ridesharing services might transfer to and/or highlight the benefits that automated ridesharing might provide. The PEOU interactions also suggest that middle-aged adults might respond more positively than younger or older adults to an educational introduction to SAVs. Conclusion: The positive findings pertaining to PU and PEOU show that exposure to information related to SAVs has a positive impact on these attitudes. PU’s and PEOU’s positive relationship to behavioral intentions (BI) in the Technology Acceptance Model, coupled with the findings from this study, bode well for higher fidelity interventions seeking to inform and/or give individuals experience with SAVs. Providing information on how currently available ridesharing services work helped our older adult respondents recognize the potential usefulness of SAVs. Knowing that different age groups may respond better to educational versus experiential interventions, for example middle-aged adults in this study responding more positively to the educational video condition than younger or older adults, may be useful for targeted promotional campaigns.

Age-related differences in the psychophysiology of the acute stress response are poorly understood given the limited number of studies and the high heterogeneity of findings. The present study contributes by investigating age differences in both the psychological and physiological responses to acute stress in a sample of healthy younger (N = 50; 18–30; Mage = 23.06; SD = 2.90) and older adults (N = 50; 65–84; Mage = 71.12; SD = 5.02). Specifically, the effects of psychosocial stress (i.e., age-adapted Trier Social Stress Test) were investigated at numerous timepoints throughout the stress response phases (i.e., baseline, anticipation, reactivity, recovery) on cortisol, heart rate, subjective stress, and anticipatory appraisal of the stressful situation. The study was conducted in a between-subject (younger vs. older) cross-over (stress vs. control) design. Results revealed age-related differences in both physiological and psychological variables: older adults had overall lower salivary cortisol levels in the stress and control conditions and lower stress-induced cortisol increase (i.e., AUCi). In addition, older adults’ cortisol reactivity was delayed compared to younger adults. Older adults showed a lower heart rate response in the stress condition while no age differences were observed in the control condition. Finally, older adults reported less subjective stress and a less negative stress appraisal during the anticipation phase than younger adults, which could potentially explain lower physiological reactivity in this age group. Results are discussed in relation to the existing literature, potential underlying mechanisms, and future directions for the field.

Although younger and older adults appear to attend to and remember emotional faces differently, less is known about age-related differences in the subjective emotional impression (arousal, potency, and valence) of emotional faces and how these differences, in turn, are reflected in age differences in various emotional tasks. In the current study, we used the same facial emotional stimuli (angry and happy faces) in four tasks: emotional rating, attention, categorical perception, and visual short-term memory (VSTM). The aim of this study was to investigate effects of age on the subjective emotional impression of angry and happy faces and to examine whether any age differences were mirrored in measures of emotional behavior (attention, categorical perception, and memory). In addition, regression analyses were used to further study impression-behavior associations. Forty younger adults (range 20–30 years) and thirty-nine older adults (range 65–75 years) participated in the experiment. The emotional rating task showed that older adults perceived less arousal, potency, and valence than younger adults and that the difference was more pronounced for angry than happy faces. Similarly, the results of the attention and memory tasks demonstrated interaction effects between emotion and age, and age differences on these measures were larger for angry than for happy faces. Regression analyses confirmed that in both age groups, higher potency ratings predicted both visual search and VSTM efficiency. Future studies should consider the possibility that age differences in the subjective emotional impression of facial emotional stimuli may explain age differences in attention to and memory of such stimuli.

Updating prior information with new information in accordance with Bayesian principles is a difficult task. Younger adult decision makers deviate from Bayes’ theorem by either overweighting prior information (i.e., using a conservatism heuristic) or overweighting new information (i.e., using a representativeness heuristic) on decision tasks without feedback. Similar to younger adults, older adults make decisions that require belief updating. Given agerelated decrements in cognitive control, older adults may be at a disadvantage compared with younger adults when updating beliefs. Prior research shows no age differences when making decisions under risk, however older adults perform worse than younger adults when making decisions under ambiguity. Currently it is unknown how older adults use heuristics when updating beliefs about risk and ambiguous information compared with younger adults. The primary aim of this dissertation was to examine age-related differences in the use of heuristics during belief updating, as well as the cognitive processes and neural correlates that underpin behaviour. In three experiments, younger and older adults completed a belief updating task with and without feedback using an urn-ball paradigm. The main results showed that both younger and older adults committed the representativeness error more than the conservatism error, with no age differences observed when updating beliefs without feedback but with younger adults updating beliefs more accurately than older adults with feedback. Further, age differences in the neural correlates that underlie belief updating showed evidence that older adults recruit additional resources in frontal regions of the brain to facilitate performance compared with younger adults. Event-related potentials showed evidence of cognitive control in response to conflicting information in both age groups, but a diminished neural response to feedback in older compared with younger adults. Additionally, while younger adults were not influenced by ambiguous information, older adults avoided committing the representativeness error only when new information was ambiguous. Last, individual differences in numeracy and cognitive reflection, but not thinking disposition, modulated belief updating performance. Together, the results show that younger and older adults can learn to update beliefs with feedback but with younger adults learning to a greater degree than older adults, especially when information is ambiguous.

Updating prior information with new information in accordance with Bayesian principles is a difficult task. Younger adult decision makers deviate from Bayes’ theorem by either overweighting prior information (i.e., using a conservatism heuristic) or overweighting new information (i.e., using a representativeness heuristic) on decision tasks without feedback. Similar to younger adults, older adults make decisions that require belief updating. Given agerelated decrements in cognitive control, older adults may be at a disadvantage compared with younger adults when updating beliefs. Prior research shows no age differences when making decisions under risk, however older adults perform worse than younger adults when making decisions under ambiguity. Currently it is unknown how older adults use heuristics when updating beliefs about risk and ambiguous information compared with younger adults. The primary aim of this dissertation was to examine age-related differences in the use of heuristics during belief updating, as well as the cognitive processes and neural correlates that underpin behaviour. In three experiments, younger and older adults completed a belief updating task with and without feedback using an urn-ball paradigm. The main results showed that both younger and older adults committed the representativeness error more than the conservatism error, with no age differences observed when updating beliefs without feedback but with younger adults updating beliefs more accurately than older adults with feedback. Further, age differences in the neural correlates that underlie belief updating showed evidence that older adults recruit additional resources in frontal regions of the brain to facilitate performance compared with younger adults. Event-related potentials showed evidence of cognitive control in response to conflicting information in both age groups, but a diminished neural response to feedback in older compared with younger adults. Additionally, while younger adults were not influenced by ambiguous information, older adults avoided committing the representativeness error only when new information was ambiguous. Last, individual differences in numeracy and cognitive reflection, but not thinking disposition, modulated belief updating performance. Together, the results show that younger and older adults can learn to update beliefs with feedback but with younger adults learning to a greater degree than older adults, especially when information is ambiguous.

This study examined age differences in working memory using a delayed-matching-to-sample (DMTS) task. Based on the inhibitory decline hypothesis, which posits that older adults are more susceptible to interference, age differences were expected to be greater for older adults when irrelevant information was present during encoding. Two experiments tested both the access and deletion functions of inhibition. In both experiments, performance was equated for older and younger participants on a no-interference version of the DMTS task to control for age differences in encoding information into working memory. Results consistently showed equivalent effects of distraction for older and younger adults regardless of the difficulty of the perceptual discrimination of targets and distractors, the degree of processing of the distractors, or the semantic relationship between targets and distractors. These results support theories that propose age differences in encoding to explain age differences in working memory, and are inconsistent with theories that propose that older adults are more susceptible to interference than younger adults.

We compared young and healthy older adults' ability to rate photos of faces and situations (e.g., sporting activities) for the degree of threat they posed. Older adults did not distinguish between more and less dangerous faces to the same extent as younger adults did. In contrast, we found no significant age differences in young and older adults' ability to distinguish between high- and low-danger situations. The differences between young and older adults on the face task were independent of age differences in older adults' fluid IQ. We discuss results in relation to differences between young and older adults on emotion-recognition tasks; we also discuss sociocognitive and neuropsychological (e.g., amygdala) theories of aging.

Engagement in potentially beneficial activities is assumed to be based partially on perceived costs and benefits. Mental fatigue may be one factor that affects perceived costs. We examined age differences in both chronic and situational mental fatigue, and their relation to task perceptions and engagement levels. Younger (M age = 32.6) and older (M age = 73.1) adults completed questionnaires measuring subjective mental fatigue, physical and mental health, and motivational states, along with several assessments of cognitive ability. In addition, assessments of effort expenditure (systolic blood pressure) and task difficulty were collected during performance of a cognitively demanding memory-scan task. Two components of chronic mental fatigue (CMF) relating to affect and motivation were identified. Although the structure of CMF did not vary with age, CMF was differentially predictive of engagement and appraisal levels across groups. As CMF-Affect levels increased, older adults' task-difficulty appraisals increased more than those of younger adults. In addition, CMF-Affect was positively associated with levels of engagement in the young, but negatively associated in the old as memory load increased. Older adults also exhibited higher levels of situational fatigue than did the young, as evidenced by increased levels of effort expenditure as both time on task and objective demands increased. However, little relationship existed between chronic and situational mental fatigue in either age group. These findings suggest that the affective aspect of CMF is particularly consequential in older adults, with both task appraisals and engagement levels being negatively affected when fatigue is high.

Participants in three age ranges (younger adults, 18–25, N = 188; middle adults, 26–49, N = 92; and older adults, 50 and over, N = 93) completed a questionnaire assessing motivations for everyday affective experiences as well as affective motivations for film viewing. In line with Arnett's (2000) view of emerging adulthood and Carstensen, Isaacowitz, and Charles's (1999) theory of socioemotional selectivity, younger adults expressed the greatest interest in experiencing negative emotions in their everyday lives, in viewing dark, creepy, or violent content, and in viewing media to escape boredom and for amusement; older adults were most interested in experiencing emotional stability and in viewing films with uplifting, heartwarming content. Results suggest that lifespan differences may help explain the allure of hedonically negative programming among some groups.

Past research showed that personality traits develop less strongly after younger adulthood, though the underlying processes remain poorly understood, and personality intervention studies scarcely investigated age differences. Also, existing findings are mostly limited to explicit assessments of personality traits (i.e., questionnaires). In this preregistered, multi-method study, we examined associations between changes in personality states and explicit and implicit trait self-concepts of emotional stability and extraversion throughout an 8-week socio-emotional intervention, 3 and 12 months later. The sample consisted of younger and older adults (N = 165, age range = 19-78 years). Findings indicate changes in personality states, explicit self-concepts for both traits, and the implicit self-concept of extraversion. Only state changes in emotional stability predicted changes in the corresponding explicit but not implicit trait self-concept. Importantly, the effects were consistent across age groups, and exploratory analyses showed higher engagement among older adults throughout the intervention. The findings emphasize that older adults might benefit as much from socio-emotional interventions as younger adults, and potential age differences in skill acquisition might be set off through engagement.

Hindsight bias – also known as the knew-it-all-along effect – is a ubiquitous judgment error affecting decision makers. Hindsight bias has been shown to vary across age groups and as a function of contextual factors, such as the decision maker’s emotional state. Despite theoretical reasons why emotions might have a stronger impact on hindsight bias in older than in younger adults, age differences in hindsight bias for emotional events remain relatively underexplored. We examined emotion and hindsight bias in younger and older adults (N = 272) against the backdrop of the 2020 U.S. presidential election. Participants predicted electoral college votes for the two presidential candidates before the election and were asked to remember their predictions approximately three weeks later, after the election results had been finalised. Republicans, for whom the electoral outcome was negatively tinged, exhibited greater hindsight bias for President Biden’s result compared with Democrats, for whom the electoral outcome was positive. The asymmetry in hindsight bias between Republicans and Democrats was similar for younger and older participants. This study suggests that negative emotions may exacerbate hindsight bias, and that adult age differences in hindsight bias observed in laboratory settings may not translate to real-world contexts.

The present study had two main objectives. The first objective was to compare the sleep architecture of young and older adults, with an emphasis on sleep spindle density and REM density. The second objective was to examine two aspects of age differences that have not been considered in previous studies: age differences in the variability of sleep measures as well as the magnitude of age differences in phasic events across the distribution of values (i.e., at each decile rather than a single measure of location such as the mean or median. A total of 24 young (mean age = 20.75±1.78 years) and 24 older (mean age = 71.17±6.15 years) adults underwent in-home polysomnography. Whole-night spindle density was significantly higher in young adults than older adults. The two age groups did not differ significantly in whole-night REM density, although significant increases in REM density across the night were observed in both age groups. These results suggest that spindle density is more affected by age than REM density. Although age differences were observed in the degree of absolute variability (older adults had significantly larger variances than young adults for sleep efficiency and time spent awake after sleep onset), a similar pattern was also observed within the two age groups: the four sleep measures with the lowest degrees of relative variability were the same and included time spent in REM and Stage 2 sleep, total sleep time, and sleep efficiency. The distributional analysis of age differences in sleep spindle density revealed that the largest age differences were initially observed in the middle of the distributions, but as the night progressed, they were seen at the upper end of the distributions. The results reported here have potential implications for the causes and functional implications of age-related changes in sleep architecture.

In three experiments age differences in attention to semantic context were examined. The performance of younger adults (ages 18–29 years) and older adults (ages 60–79 years) on a semantic priming task indicated that both age groups could use information regarding the probability that a prime and target would be related to flexibly anticipate the target category given the prime word (Experiment 1). The timing by which target expectancies were reflected in reaction time performance was delayed for older adults as compared to younger adults, but only when the target was expected to be semantically unrelated to the prime word (Experiment 2). When the target and prime were expected to be semantically related, the time course of priming effects was similar for younger and older adults (Experiment 3). Together the findings indicate that older adults are able to use semantic context and the probability of stimulus relatedness to anticipate target information. Although aging may be associated with a delay in the timing by which controlled expectancies are expressed, these findings argue against an age-related decline in the ability to represent contextual information.