Todd C. Handy’s research while affiliated with University of British Columbia and other places

Efforts to understand the effects of physical activity on cognitive health have long relied on employing objective measures that assess the efficacy of the mechanics of cognition. However, this perspective overlooks complementary dimensions of cognitive functioning, namely one’s subjective appraisal of the efficacy of their cognitive mechanics. In a set of four investigations (N = 2965), we sought to discern whether physical activity (PA), and other health and demographic factors, contribute to subjective experiences of cognitive mechanics (SCF) and to map for future investigations domains of function that are sensitive to health factors. We employed linear multiple regression analyses to examine survey data collected online from four large samples of young adults who responded to measures of health behaviours and SCF. PA contributed to subjective experiences of attentional control and spatial navigation but not memory, executive function, or general cognitive functioning. Further, sleep, diet, and stress were each consistently associated with selective measures of subjective experiences of cognition. Taken together, these studies indicate the importance of PA, as well as additional health behaviours, as significant contributors to SCF.

Background Evidence from randomized controlled trials (RCTs) shows that aerobic exercise (AE) can benefit cognitive function among older adults with mild cognitive impairment (MCI). Growing research suggests that outdoor, natural (i.e., “green”) environments, compared with indoor or built environments, may augment the health benefits of exercise. However, the potential cognitive benefits of green exercise are unclear. We compared the effects of AE performed in an outdoor, green environment (O‐Ex) versus indoor AE (I‐Ex) on executive functions among older adults with MCI. Methods A two‐arm parallel, single‐blinded, 12‐week proof‐of‐concept RCT. 72 community‐dwelling adults aged 65‐80 years with MCI were randomized (1:1) to either O‐Ex (n = 36) or I‐Ex (n = 36). Each arm involved two group‐based training sessions per week. Each session involved 10 min warm‐up, 40 min moderate‐intensity AE (progressing from 45%–75% of heart rate reserve), and 10 min cool‐down. We monitored exercise intensity using heart rate monitors and Borg’s 20‐point Rating of Perceived Exertion. AE consisted of outdoor walking in an urban forest (O‐Ex) or indoor treadmill walking or stationary cycling (I‐Ex). We measured working memory using the National Institutes of Health Toolbox (NIHTB) List Sorting Test and the Verbal Digits Forward and Backward Test. We measured set shifting and response inhibition using the NIHTB Dimensional Change Card Sort Test and Flanker Test, respectively. We performed a complete case analysis using a one‐way analysis of covariance to compare groupwise changes in executive functions (NIHTB corrected T‐score), with baseline outcome score and baseline Montreal Cognitive Assessment (MoCA) score as covariates. Overall alpha was ≤0.05. Results Mean baseline MoCA score was 22.36 (SD = 2.55). Mean age was 74.08 years (SD = 3.92). There were 26 males and 46 females. The attrition rate was 12.5% (O‐Ex = 5; I‐Ex = 4). At 12 weeks, after adjusting for baseline outcome and baseline MoCA scores, O‐Ex had significantly better scores than I‐Ex for set shifting (estimated mean difference: 7.46; 95% CI: [2.69, 12.23]; p = 0.003) and response inhibition (estimated mean difference: 3.81; 95% CI: [0.61, 7.01]; p = 0.021), but not for working memory. Conclusions Aerobic exercise performed outdoors in nature, compared with indoor aerobic exercise, may provide greater cognitive benefits among older adults with MCI.

Our cognitive capacities like working memory and attention are known to systematically vary over time with our physical activity levels, dietary choices, and sleep patterns. However, whether our metacognitive capacities––such as our strategic use and optimization of cognitive resources––show a similar relationship with these key lifestyle factors remains unknown. Here we addressed this question in healthy young adults by examining if physical activity, diet, and sleep patterns were predictive of self-reported metacognitive status. Participants completed a set of validated surveys assessing these lifestyle factors over the past week to month, as well as three measures of metacognition. Using multiple regression and exploratory factor analyses we identified four clusters of metacognitive processes that are sensitive to lifestyle behaviours. Specifically, knowledge of and offline regulation of cognition is linked with physical activity, on-line cognitive regulation is related to diet, and metacognitive worry is associated with sleep behaviours. These findings suggest that lifestyle behaviours do not just affect objective cognitive functioning, but also the meta-level processes we use to monitor our cognitive performance and exert strategic control over our cognitive resources.

Neuroendocrine changes during perimenopause negatively impact cognitive function and brain health (e.g., reduced verbal episodic memory and myelin catabolism in the brain). Exercise promotes cognitive performance and mitigates vascular risk factors for cognitive impairment. High-intensity interval training (HIIT) involves short bursts of high-intensity exercise interspersed with active recovery; it improves cardiovascular fitness and vascular risk profile. HIIT addresses the “lack of time” barrier to exercise that perimenopausal females report. This pre-post pilot study assessed the feasibility and potential effects of 12-weeks of HIIT on cardiovascular fitness, verbal episodic memory, hippocampal volume, and myelin content. Feasibility metrics included recruitment rate (i.e., 1/month), withdrawal rate (i.e., < 15%), adherence (i.e., >60%). Training fidelity was assessed by cardiovascular fitness (VO2max.) Verbal episodic memory was assessed by Rey Auditory Verbal Learning Test delayed recall. Hippocampal volume was measured by T1-weighted magnetic resonance imaging. Myelin content was measured by myelin water fraction. Cohen’s d and one-tailed paired t-tests assessed effect sizes and potential changes. Recruitment rate was 0.35 participants/month (six participants in 17 months). Withdrawal rate was 16.67% and adherence was 88.2%. The intervention had a negligible effect on VO2max (Cohen’s d=0.06, p=0.35), large and significant effect on delayed recall (Cohen’s d=0.94, p=0.04), negligible effect on hippocampal volume (Cohen’s d=0.06, p=0.18), and medium to large effect on sagittal stratum myelin content (Cohen’s d=0.68, p=0.06). Future studies should consider home-based exercise and tailored recruitment methods (e.g. social media) to meet recruitment targets. HIIT may be beneficial for cognitive function and myelin content.

Misokinesia, the reduced tolerance to others’ repetitive bodily movements, impacts individuals’ personal, social, and professional lives. The present study aimed to elucidate the factors contributing to Misokinesia Sensitivity (MKS) by exploring the subjective experiences of affected individuals, thereby guiding future empirical research and informing clinical awareness. Using a qualitative approach, we conducted semi-structured interviews with 21 participants from an online support group on Facebook. Data were analyzed through thematic analysis to uncover patterns and themes in their lived experiences. The thematic analysis revealed three main themes: internal cognitive and affective impacts, external social impacts, and pragmatic factors related to MKS triggers and responses. These findings provide a foundational understanding of MKS, highlighting its significant personal and social consequences and suggesting areas for targeted interventions. The insights gained aim to enhance clinical recognition and support the development of effective management strategies for those affected by MKS.

The aim of the study is to understand how Mirror Neuron System (MNS) and Mentalizing Network (MZN) interact with each other. EEG data was collected during a photo judgment task with pictures of actions or facial expressions. Participants (N = 30, 63% women) were asked to either identify how the shown action/expression was being performed (MNS) or what the goal or intention behind the action was (MZN). Data were analyzed using microstate analysis, source localization and Event-Related Potentials. When comparing the action types, we found early divergence between the brain states of MNS and MZN when comparing the same action type. There was temporal alignment between the start and end time of the induced microstates, among the same action type. Between different action types, the timing was slightly shifted. Temporally, there was a greater overlap between the timing of the states between networks within the same action type as compared to within networks across action types. The MNS and MZN are acting in parallel rather then subsequently and possibly feed into each other. Furthermore, the MNS and MZN do not specifically react to one action type over the other, but their activity is influenced by the action type.

Misokinesia is a prevalent condition characterized by strong, negative emotional reactions to the sight of repetitive fidgeting movements in others. Here we present the results of a study designed to explore the relationship between misokinesia sensitivity (MKS) and attentional sensitivity to affectively-valenced visual stimuli. In particular, we asked participants with either high or low levels of MKS to perform an emotional oddball task that included responding to faces that had either angry or happy expressions, while we recorded event-related potentials. We found that there were no significant differences between the two MKS groups in attentional sensitivity to these faces, as indexed by the amplitude of the P300 ERP component they elicited. Importantly, we could not ascribe this null ERP finding to either low statistical power or the idiosyncrasies of our ERP analysis parameters. As such, our findings add to growing evidence that MKS may not be the simple result of heightened attentional orienting responses to visual events, but rather, it may be associated with other aspects of cognitive-affective processing.

Background Slower walking is associated with changes in cortical volume and thickness. Computerized cognitive training (CCT) and exercise improve cortical volume and thickness and thus, may promote gait speed. Slowing of gait is predictive of Alzheimer’s disease. Objective To examine: 1) the effect of CCT, with or without physical exercise, on cortical volume and thickness and; 2) the association of changes in cortical volume and thickness with changes in gait speed. Methods A subset of 124 adults (n = 53), aged 65–85 years, enrolled in an 8-week randomized controlled trial and completed T1-weighted MRI and 4-meter walk at baseline and 8 weeks. Participants were randomized to: 1) active control (BAT; n = 19); 2) CCT (n = 17); or 3) CCT preceded by exercise (Ex-CCT; n = 17). Change in cortical volume and thickness were assessed and compared across all groups using Freesurfer. RESULTS BAT versus CCT increased left rostral middle frontal gyrus volume (p = 0.027) and superior temporal gyrus thickness (p = 0.039). Ex-CCT versus CCT increased left cuneus thickness (p < 0.001) and right post central gyrus thickness (p = 0.005), and volume (p < 0.001). Ex-CCT versus BAT increased left (p = 0.001) and right (p = 0.020) superior parietal gyri thickness. There were no significant between-group differences in gait speed (p > 0.175). Increased left superior parietal volume (p = 0.036, r = 0.340) and thickness (p = 0.002, r = 0.348), right post central volume (p = .017, r = 0.341) and thickness (p = 0.001, r = 0.348), left banks of superior temporal sulcus thickness (p = 0.002, r = 0.356), and left precuneus thickness (p < 0.001, r = 0.346) were associated with increased gait speed. CONCLUSIONS CCT with physical exercise, but not CCT alone, improves cortical volume and thickness in older adults. These changes may contribute to the maintenance of gait speed in aging.

Background The world’s population is aging and thus, it is important that we find strategies to reduce the rate of age‐related cognitive decline. Lifestyle interventions can play an important role in delaying the onset of cognitive decline. Evidence shows both computerized cognitive training (CCT) or exercise can improve cognitive function. However, the effect of CCT on cortical structure is not well understood. This study examines the effect of 8‐weeks of CCT, with or without a preceding exercise bout, on cortical structure in community‐dwelling older adults. Method Structural magnetic resonance imaging (MRI) data acquired from an 8‐week, 3‐arm, proof of concept randomized controlled trial was used. Participants (N = 125) aged 65 – 85 were randomized (1:1:1) to either 8 weeks of 3x/week: 1) Balance and Toned (BAT; active control); 2) CCT; or 3) Exercise + CCT (Ex‐CCT). Measurement occurred at baseline and trial completion (i.e., 8‐weeks). Fifty‐three participants with baseline and trial completion MRI data were included in this analysis. Freesurfer was used to assess BAT vs. CCT, BAT vs. Ex‐CCT, and CCT vs. Ex‐CCT differences in cortical thickness and volume at trial completion, adjusting for age, sex, and Montreal Cognitive Assessment (MoCA) score. Result At trial completion, CCT vs. BAT decreased left rostral middle frontal gyrus volume (cluster size = 553.51 mm2, cluster‐wise p = .027) and left superior temporal gyrus thickness (cluster size = 525.58 mm ² , cluster‐wise p = .039). Ex‐CCT vs. BAT increased cortical thickness in the left (cluster size = 900.23 mm2, cluster‐wise p = .001) and right (cluster size = 681.95 mm2, cluster‐wise p = .020) superior parietal gyri. Finally, Ex‐CCT vs. CCT increased left cuneus thickness (cluster size = 1062.12 mm ² , cluster‐wise p < .001) as well as right post central gyrus thickness (cluster size = 714.85 mm ² , cluster‐wise p = .005) and volume (cluster size = 1030.08 mm ² , cluster‐wise p < .001). Conclusion Eight weeks of CCT with exercise is of sufficient duration to induce structural change in the brain. Moreover, exercise may enhance the effect of CCT on cortical grey matter structure vs. CCT alone.

Background Neighbourhood nature spaces are associated with brain health. Biological sex moderates the associations of various lifestyle and environmental factors with brain health, but it is unclear whether sex moderates associations between nature exposure and brain structure. We thus investigated whether sex moderates the association of residential nature exposure with brain structure in the UK Biobank cohort. Methods We conducted a cross‐sectional analysis of the UK Biobank study. We included cognitively healthy participants with available nature exposure data at study entry (2006‐2010) who completed a 3T structural brain MRI (2014‐2021; N = 37,880). Residential nature exposure was estimated as the percentage of land classified as natural environment within 1000m of a participant’s home. We indexed total grey matter volume and total white matter volume, normalized for head size, and hippocampal volume averaged from both hemispheres. We performed linear regressions to assess the independent associations of residential nature exposure and biological sex with brain structure. We then assessed whether sex moderated the association between residential nature exposure and brain structure, and plotted simple slopes to interpret interaction effects. All models adjusted for age, body mass index (kg/m ² ), educational attainment, income, physical activity (min/day), time spent outdoors (hours/day), smoking status, disability status, Townsend deprivation index, and population density. Results At study entry, mean age was 55 years (SD = 7.53 years) and 53% of participants were female. Average residential nature exposure was 44% (SD = 26%). Every 10% increment in residential nature exposure was associated with 737 mm ³ greater grey matter volume (p<0.0001) and 601 mm ³ greater white matter volume (p<0.0001). Females had 24,270 mm ³ greater grey matter volume (p<0.0001), 9,703 mm ³ less white matter volume (p<0.0001), and 223 mm ³ less hippocampal volume than males (p<0.0001). Sex moderated the association of residential nature exposure with total grey matter volume, such that every 10% increment in nature exposure attenuated sex differences in grey matter volume by 422 mm ³ (p = 0.020) (Figure 1). Conclusion These results suggest that neighbourhood nature spaces may benefit brain health, and that males may be more sensitive than females to these potential benefits. Longitudinal analyses are needed to verify these findings.