Differential impacts of healthy cognitive aging on directed and random exploration.

Deciding whether to explore unknown opportunities or exploit well-known options is a ubiquitous part of our everyday lives. Extensive work in college students suggests that young people make explore-exploit decisions using a mixture of information seeking and random behavioral variability. Whether, and to what extent, older adults use the same strategies is unknown. To address this question, 51 older adults (ages 65-74) and 32 younger adults (ages 18-25) completed the Horizon Task, a gambling task that quantifies information seeking and behavioral variability as well as how these strategies are controlled for the purposes of exploration. Qualitatively, we found that older adults performed similar to younger adults on this task, increasing both their information seeking and behavioral variability when it was adaptive to explore. Quantitively, however, there were substantial differences between the age groups, with older adults showing less information seeking overall and less reliance on variability as a means to explore. In addition, we found a subset of approximately 26% of older adults whose information seeking was close to zero, avoiding informative options even when they were clearly the better choice. Unsurprisingly, these "information avoiders" performed worse on the task. In contrast, task performance in the remaining "information seeking" older adults was comparable to that of younger adults suggesting that age-related differences in explore-exploit decision making may be adaptive except when they are taken to extremes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Associations between physical exercise type, fluid intelligence, executive function, and processing speed in the oldest-old (85 +).

BACKGROUND: While much is known about the effects of physical exercise in adult humans, literature on the oldest-old (≥ 85 years old) is sparse. The present study explored the relationship between self-reported engagement in physical exercise and cognition in the oldest-old. METHODS: The sample included 184 cognitively healthy participants (98 females, MoCA mean score = 24.81) aged 85 to 99 years old (mean = 88.49 years). Participants completed the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire and a cognitive battery including NIH-TB, Coding, Symbol Search, Letter Fluency, and Stroop task. Three groups of participants - sedentary (n = 58; MoCA mean score = 24; 36 females; mean age = 89.03), cardio (n = 60; MoCA mean score = 25.08; 29 females; mean age = 88.62), and cardio + strength training (n = 66; MoCA mean score = 25.28; 33 females; mean age = 87.91) - were derived from responses on CHAMPS. RESULTS: Analyses controlled for years of education, NIH-TB Crystallized Composite, and metabolic equivalent of tasks. The cardio + strength training group had the highest cognitive performances overall and scored significantly better on Coding (p < 0.001) and Symbol Search (p < 0.05) compared to the sedentary group. The cardio + strength training group scored significantly better on Symbol Search, Letter Fluency, and Stroop Color-Word compared to the cardio group (p < 0.05). CONCLUSIONS: Our findings suggest self-reported exercise in the oldest-old is linked to better performance on cognitive measures of processing speed and executive functioning, and that there may be a synergistic effect of combining aerobic and resistance training on cognition.

Interaction of Age and Self-reported Physical Sports Activity on White Matter Hyperintensity Volume in Healthy Older Adults.

Cerebral white matter (WM) lesion load, as measured by white matter hyperintensity (WMH) volume with magnetic resonance imaging (MRI), has been associated with increasing age and cardiovascular risk factors, like hypertension. Physical sports activity (PSA) may play an important role in maintaining WM in the context of healthy aging. In 196 healthy older adults, we investigated whether participants reporting high levels of PSA (n = 36) had reduced total and regional WMH volumes compared to those reporting low levels of PSA (n = 160). Age group [young-old (YO) = 50-69 years; old-old (OO) = 70-89 years], PSA group, and age by PSA group interaction effects were tested, with sex, hypertension, and body mass index (BMI) as covariates. We found significant main effects for age group and age by PSA group interactions for total, frontal, temporal, and parietal WMH volumes. There were no main effects of PSA group on WMH volumes. The OO group with low PSA had greater total, frontal, temporal, and parietal WMH volumes than the YO with low PSA and OO with high PSA groups. WMH volumes for the YO and OO groups with high PSA were comparable. These findings indicate an age group difference in those with low PSA, with greater WMH volumes in older adults, which was not observed in those with high PSA. The results suggest that engaging in high levels of PSA may be an important lifestyle factor that can help to diminish WMH lesion load in old age, potentially reducing the impact of brain aging.

Effects of simultaneous cognitive and aerobic exercise training on dual-task walking performance in healthy older adults: results from a pilot randomized controlled trial.

BACKGROUND: The ability to walk and perform cognitive tasks simultaneously is a key aspect of daily life. Performance declines in these dual-tasks may be associated with early signs of neurodegenerative disease and increased risk of falls. Thus, interventions to improve dual-task walking performance are of great interest for promoting healthy aging. Here, we present results of a pilot randomized controlled trial (RCT) to evaluate the effects of a simultaneous aerobic exercise and cognitive training intervention on dual-task walking performance in healthy older adults. METHODS: Community-dwelling, healthy older adults were recruited to participate in a 12-week RCT. Participants were randomized into one of four groups (n = 74): 1) cognitive training (COG), 2) aerobic exercise (EX), 3) combined aerobic exercise and cognitive training (EXCOG), and 4) video-watching control (CON). The COG and EXCOG groups both used a tablet-based cognitive training program that challenged aspects of executive cognitive function, memory, and processing speed. Performance on a dual-task walking test (DTWT; serial subtraction during two-minute walk) was assessed by researchers blinded to groupings before the intervention, and at 6 and 12 weeks. We included all participants randomized with baseline measurements in an intention to treat analysis using linear mixed effects models. RESULTS: We found a significant group by time interaction for cognitive performance on the DTWT (p = 0.039). Specifically, participants in the EXCOG, EX, and COG groups significantly improved on the cognitive aspect of the DTWT following the full 12-week intervention (p = 3.5e-7, p = 0.048, p = 0.048, respectively). The improvements in EXCOG were twice as large as in the other groups, and were significant at 6 weeks (p = 0.019). The CON group did not show a significant change in cognitive performance on the DTWT, and no group significantly altered dual-task gait measures following the intervention. CONCLUSIONS: A simultaneous aerobic exercise and cognitive training intervention significantly improved cognitive performance during a DTWT in healthy older adults. Despite no change in DTWT gait measures, significant improvements in cognitive performance indicate that further investigation in a larger RCT is warranted. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04120792, Retrospectively Registered 08 October 2019.

Depressive symptoms and inductive reasoning performance: findings from the ACTIVE reasoning training intervention.

Within the context of the Advanced Cognitive Training for Independent and Vital Elderly study (ACTIVE; Ball et al., 2002; Jobe et al., 2001; Willis et al., 2006), we examined the longitudinal association of baseline depressive symptoms on inductive reasoning performance over a 10-year period between the reasoning training and control conditions (N = 1,375). At baseline, 322 participants (23%) reported elevated depressive symptoms, defined by a score ≥9 on the 12-item version of the Center for Epidemiological Studies Depression Scale (CES-D; Mirowsky & Ross, 2003; Radloff, 1977). Differences in baseline depressive status were not associated with immediate posttraining gains or with subsequent annual change in reasoning performance, suggesting that the presence of elevated baseline depressive symptoms does not impact the ability to benefit from reasoning training.

Non-pharmacological prevention of major depression among community-dwelling older adults: a systematic review of the efficacy of psychotherapy interventions.

Depression is a major public health burden among the aging population. While older adults prefer non-pharmacological treatment, few options for psychotherapy are available in primary care settings, which is where older adults tend to receive mental health services. Indicated prevention is a cost-effective, public health approach to prevent major depressive disorder among people with depressive symptoms who do not yet meet standard criteria for major depression. We critically reviewed randomized controlled trials (RCTs) that assessed the efficacy of psychotherapy among community-dwelling older adults with subthreshold depression (depressive symptoms that do not meet standard criteria for major depression). We examined the intervention types, results, internal validity, and external validity of five studies. We used the United States Preventive Services Task Force (USPSTF) guidelines to rate the quality of the studies and to provide recommendations. Results suggest that psychotherapy is a safe and cost-effective method to reduce the public health burden of depression among older adults with subthreshold depression.