Neurobehavioral mechanisms underlying the effects of physical exercise break on episodic memory during prolonged sitting

Ten-Minute Physical Activity Breaks Improve Attention and Executive Functions in Healthcare Workers

Occupational health is a major problem in modern work environments. Physical activity breaks (PABs), short exercise periods delivered during working hours, incorporating exergames or outdoor activities, have emerged as a novel approach that could be used to improve work efficiency and workplace wellbeing. Therefore, this study aimed to investigate the impact of PABs on attention levels and executive functions in healthcare workers. A total of 27 healthcare workers (M = 14, W = 13; 49.55 ± 12.46 years), after 4 h of work, randomly performed one of three 10 min conditions weekly in a counterbalanced order: No Physical Activity Break (NPAB); Outdoor Physical Activity Break (OPAB); Physical Activity Break with Exergame (PABEx). After the conditions, executive functions and selective attention were assessed by the Stroop Color and Word Test (SCWT), and the Trail Making A,B test (TMT A,B), respectively. Significant differences between OPAB and NPAB as well as between PABEx and NPAB in the TMT-A test χ2(2) = 44.66 (p < 0.001) and TMT-B test χ2(2) = 48.67 (p < 0.001) were found, respectively. TMT-A and SCWT interference/time scores of the PABEx and OPAB conditions were significantly lower than those of NPAB (p < 0.001). In the SCWT interference/error score, no significant difference was found between the PABEx and NPAB (p > 0.05), but the score was statistically lower in the OPAB condition than PABEx (p = 0.001) and PABEx condition compared to OPAB for TMT-A (p = 0.001). Findings showed that the OPAB and PABEx conditions are effective in improving selective attention and executive functions in healthcare workers. Employers can foster a healthier and more productive workforce by promoting a culture of movement and prioritizing employee health, which in turn can enhance patient care outcomes.

Sedentary behavior and lifespan brain health

Higher levels of physical activity are known to benefit aspects of brain health across the lifespan. However, the role of sedentary behavior (SB) is less well understood. In this review we summarize and discuss evidence on the role of SB on brain health (including cognitive performance, structural or functional brain measures, and dementia risk) for different age groups, critically compare assessment approaches to capture SB, and offer insights into emerging opportunities to assess SB via digital technologies. Across the lifespan, specific characteristics of SB (particularly whether they are cognitively active or cognitively passive) potentially act as moderators influencing the associations between SB and specific brain health outcomes. We outline challenges and opportunities for future research aiming to provide more robust empirical evidence on these observations.

Modulatory effects of aerobic training on the degree centrality of brain functional activity in subthreshold depression

BACKGROUND

Aerobic training has been shown to effectively prevent the progression of depressive symptoms from subthreshold depression (StD) to major depressive disorder (MDD), and understanding how aerobic training promotes changes in neuroplasticity is essential to comprehending its antidepressant effects. Few studies, however, have quantified the alterations in spontaneous brain activity before and after aerobic training for StD.

METHODS

Participants included 44 individuals with StD and 34 healthy controls (HCs). Both groups underwent moderate aerobic training for eight weeks, and resting state functional magnetic resonance imaging (rs-fMRI) data were collected before and after training. The degree centrality (DC) changes between the two groups and the DC changes in each group before and after training were quantified.

RESULTS

The rs-fMRI results showed that compared with the HCs, the DC values of the StD group in the orbital region of the left inferior frontal gyrus significantly depreciated at baseline. After aerobic training, the results of the follow-up examination revealed no significant difference in the DC values between the two groups. In addition, compared with baseline, the StD group exhibited an significant decrease in the DC values of the left dorsolateral superior frontal gyrus; while the HCs group exhibited an significant decrease in the DC values of the left thalamus. No statistically significant connection was seen between changes in DC values and psychological scale scores in the StD group.

CONCLUSIONS

Our findings suggest that regular aerobic training can enhance brain plasticity in StD. In addition, we demonstrated that DC is a relevant and accessible method for evaluating the functional plasticity of the brain induced by aerobic training in StD.

Effects of Mind-Body Qigong Exercise on Overall Health, Fatigue/Sleep, and Cognition in Older Chinese Immigrants in the US: An Intervention Study with Control

Background

Culturally relevant exercises may help improve health and address disparities faced by older immigrants due to language and cultural barriers. Few studies have focused on such exercise interventions among older Chinese immigrants at US daycare centers.

Methods

We conducted a 10-week nonrandomized controlled trial in older Chinese immigrants in Philadelphia, US. The intervention group practiced Chinese Qigong (Baduanjin) 5 days a week guided by trained research assistants and video instructions. The control group maintained their usual daily activities. We collected self-report assessments on overall health, sleep, and fatigue and implemented two computerized cognitive tests measuring psychomotor vigilance task (PVT) and memory twice, preintervention and postintervention. Repeated measures general linear model (GLM) and paired samples t-tests were used for data analyses.

Results

Eighty-eight older adults (Qigong, n = 53; control, n = 35) with an average age of 78.13 (SD = 5.05) were included. Groups showed no significant differences at baseline evaluation. After the 10-week exercise, the intervention group showed significant improvements in overall health (p=0.032), fatigue (p < 0.001), and cognitive functions including memory (p=0.01), response speed (p=0.002), and response time (p=0.012) on the PVT, as well as marginally significant benefits in sleep (p=0.058). Between-group comparisons identified significant group-by-time interactions in health (p=0.024), sleep (p=0.004), fatigue (p=0.004), and memory (p=0.004).

Conclusion

We revealed significant positive effects of Qigong in older Chinese immigrants across multiple health domains. Findings highlight the potential of a culturally relevant exercise in addressing health disparities.

Association of physical activity and fitness with executive function among preschoolers

It is well-documented in the literature that high levels of regular physical activity (PA), low levels of sedentary behavior (SB), and high levels of cardiorespiratory fitness (CRF) are associated with superior cognitive functioning, especially with regard to older populations. However, concerning other age groups (e.g., preschoolers) the available evidence documenting such a positive relationship is relatively scarce. Thus, this study aimed to investigate the association of time spent in different PA intensity zones and CRF with executive functions (EFs) in preschool-age children. To this end, preschoolers (n = 127) aged 3 to 6 years were recruited from 9 kindergarten classes in 2 districts of Shenzhen, China. The amount and the intensity of PA were assessed via accelerometry, and the CRF level was quantified by the 20-meter shuttle run test. EFs including inhibitory control and working memory were assessed using the one-on-one iPad-based Early Year Toolbox. Results suggested that children who had a higher CRF level ("impulse control" scores: β = 0.34, p < .001; "Go" accuracy: β = 0.31, p < .001; "No-Go" accuracy: β =0.28, < .001) and spentmore time in moderate-to-vigorous physical activity (MVPA) ("impulse control" scores: β = 0.50, p < .001; No-Go" accuracy: β = 0.52, p < .001) had higher scores on inhibitory control tasks, and those who had a higher CRF level had higher scores on a working memory task (β = 0.24, p < .05). The findings are discussed in light of the positive roles of MVPA and CRF for promoting EFs, but also consider the disproportionate association of PA and CRF with working memory relative to inhibition.

Cortical activation of neuromuscular electrical stimulation synchronized mirror neuron rehabilitation strategies: an fNIRS study

Background

The mirror neuron system (MNS) plays a key role in the neural mechanism underlying motor learning and neural plasticity. Action observation (AO), action execution (AE), and a combination of both, known as action imitation (AI), are the most commonly used rehabilitation strategies based on MNS. It is possible to enhance the cortical activation area and amplitude by combining traditional neuromuscular electrical stimulation (NMES) with other top-down and active rehabilitation strategies based on the MNS theory.

Objective

This study aimed to explore the cortical activation patterns induced by NMES synchronized with rehabilitation strategies based on MNS, namely NMES+AO, NMES+AE, and NMES+AI. In addition, the study aimed to assess the feasibility of these three novel rehabilitative treatments in order to provide insights and evidence for the design, implementation, and application of brain-computer interfaces.

Methods

A total of 70 healthy adults were recruited from July 2022 to February 2023, and 66 of them were finally included in the analysis. The cortical activation patterns during NMES+AO, NMES+AE, and NMES+AI were detected using the functional Near-Infrared Spectroscopy (fNIRS) technique. The action to be observed, executed, or imitated was right wrist and hand extension, and two square-shaped NMES electrodes were placed on the right extensor digitorum communis. A block design was adopted to evaluate the activation intensity of the left MNS brain regions.

Results

General linear model results showed that compared with the control condition, the number of channels significantly activated (PFDR < 0.05) in the NMES+AO, NMES+AE, and NMES+AI conditions were 3, 9, and 9, respectively. Region of interest (ROI) analysis showed that 2 ROIs were significantly activated (PFDR < 0.05) in the NMES+AO condition, including BA6 and BA44; 5 ROIs were significantly activated in the NMES+AE condition, including BA6, BA40, BA44, BA45, and BA46; and 6 ROIs were significantly activated in the NMES+AI condition, including BA6, BA7, BA40, BA44, BA45, and BA46.

Conclusion

The MNS was activated during neuromuscular electrical stimulation combined with an AO, AE, and AI intervention. The synchronous application of NMES and mirror neuron rehabilitation strategies is feasible in clinical rehabilitation. The fNIRS signal patterns observed in this study could be used to develop brain-computer interface and neurofeedback therapy rehabilitation devices.

Associations between sedentary behavior and negative emotions in adolescents during home confinement: Mediating role of social support and sleep quality

Background

Prolonged periods of sedentary behaviour, for instance, engendered by home confinement in Shenzhen city, has led to negative mental health consequences, especially in adolescents. Previous research suggests, in general, that sedentary behavior can increase negative emotions. However, the specific mechanism driving the relationship between sedentary behavior and negative emotions is still relatively unclear. Social support and sleep quality might partly explain the effect of sedentary behavior on negative emotions. Thus, the current study aimed to examine the associations between sedentary behavior and negative emotions, and to investigate if social support and sleep quality mediate such a relationship.

Method

During home confinement due to the COVID-19 Omicron variant outbreak, 1179 middle and high school students in Shenzhen were invited to voluntarily complete an e-questionnaire, including the 21-item Depression Anxiety Stress Scale (DASS-21), the short form of the International Physical Activity Questionnaire (IPAQ-SF), the Social Support Rating Scale (SSRS) and the Pittsburgh Sleep Quality Index (PSQI). Data from 1065 participants were included in the analysis.

Results

We observed significant sex-related and demografic-related differences in emotional (e.g., anxiety, stress and social support) and other outcome variables (e.g., sitting duration and PSQI score). Furthermore, sedentary behavior, social support, and sleep quality were associated with negative emotions (p < .01), even after controlling for sex, age, only-child case, body mass index, and metabolic equivalent level. In addition, social support and sleep quality partially mediated the association between sedentary behavior and negative emotions.

Conclusion

The findings of the current study suggest that social support and sleep quality partially mediate the relationship between sedentary behavior and negative emotions in middle and high school students during home confinement in Shenzhen city.

Tai Chi practice enables prefrontal cortex bilateral activation and gait performance prioritization during dual-task negotiating obstacle in older adults

BACKGROUND

With aging, the cognitive function of the prefrontal cortex (PFC) declined, postural control weakened, and fall risk increased. As a mind-body exercise, regular Tai Chi practice could improve postural control and effectively prevent falls; however, underlying brain mechanisms remained unclear, which were shed light on by analyzing the effect of Tai Chi on the PFC in older adults by means of functional near-infrared spectroscopy (fNIRS).

METHODS

36 healthy older adults without Tai Chi experience were divided randomly into Tai Chi group and Control group. The experiment was conducted four times per week for 16 weeks; 27 participants remained and completed the experiment. Negotiating obstacle task (NOT) and negotiating obstacle with cognitive task (NOCT) were performed pre- and post-intervention, and Brodmann area 10 (BA10) was detected using fNIRS for hemodynamic response. A three-dimensional motion capture system measured walking speed.

RESULTS

After intervention in the Tai Chi group under NOCT, the HbO2 concentration change value (ΔHbO2) in BA10 was significantly greater (right BA10: p = 0.002, left BA10: p = 0.001), walking speed was significantly faster (p = 0.040), and dual-task cost was significantly lower than pre-intervention (p = 0.047). ΔHbO2 in BA10 under NOCT was negatively correlated with dual-task cost (right BA10: r = -0.443, p = 0.021, left BA10: r = -0.448, p = 0.019). There were strong negative correlations between ΔHbO2 and ΔHbR under NOCT either pre-intervention (left PFC r = -0.841, p < 0.001; right PFC r = -0.795, p < 0.001) or post-intervention (left PFC r = -0.842, p < 0.001; right PFC r = -0.744, p < 0.001).

CONCLUSION

Tai Chi practice might increase the cognitive resources in older adults through the PFC bilateral activation to prioritize gait performance during negotiating obstacles under a dual-task condition.