Cognitive aging affects motor performance and learning

Neural Underpinnings of Learning in Dementia Populations: A Review of Motor Learning Studies Combined with Neuroimaging

The intent of this review article is to serve as an overview of current research regarding the neural characteristics of motor learning in Alzheimer disease (AD) as well as prodromal phases of AD: at-risk populations, and mild cognitive impairment. This review seeks to provide a cognitive framework to compare various motor tasks. We will highlight the neural characteristics related to cognitive domains that, through imaging, display functional or structural changes because of AD progression. In turn, this motivates the use of motor learning paradigms as possible screening techniques for AD and will build upon our current understanding of learning abilities in AD populations.

Using virtual reality-based neurocognitive testing and eye tracking to study naturalistic cognitive-motor performance

Natural human behavior arises from continuous interactions between the cognitive and motor domains. However, assessments of cognitive abilities are typically conducted using pen and paper tests, i.e., in isolation from "real life" cognitive-motor behavior and in artificial contexts. In the current study, we aimed to assess cognitive-motor task performance in a more naturalistic setting while recording multiple motor and eye tracking signals. Specifically, we aimed to (i) delineate the contribution of cognitive and motor components to overall task performance and (ii) probe for a link between cognitive-motor performance and pupil size. To that end, we used a virtual reality (VR) adaptation of a well-established neurocognitive test for executive functions, the 'Color Trails Test' (CTT). The VR-CTT involves performing 3D reaching movements to follow a trail of numbered targets. To tease apart the cognitive and motor components of task performance, we included two additional conditions: a condition where participants only used their eyes to perform the CTT task (using an eye tracking device), incurring reduced motor demands, and a condition where participants manually tracked visually-cued targets without numbers on them, incurring reduced cognitive demands. Our results from a group of 30 older adults (>65) showed that reducing cognitive demands shortened completion times more extensively than reducing motor demands. Conditions with higher cognitive demands had longer target search time, as well as decreased movement execution velocity and head-hand coordination. We found larger pupil sizes in the more cognitively demanding conditions, and an inverse correlation between pupil size and completion times across individuals in all task conditions. Lastly, we found a possible link between VR-CTT performance measures and clinical signatures of participants (fallers versus non-fallers). In summary, performance and pupil parameters were mainly dependent on task cognitive load, while maintaining systematic interindividual differences. We suggest that this paradigm opens the possibility for more detailed profiling of individual cognitive-motor performance capabilities in older adults and other at-risk populations.

Effect of intensive water resistance phonation therapy for people with presbyphonia: A pilot study

Purpose: The aim of this pilot study was to explore the efficacy of an intensive 3 week water resistance phonation (WRP) therapy program for people with presbyphonia.Method: Participants included 13 people with presbyphonia who received intensive WRP therapy. All participants completed eight sessions of therapy over 3 weeks. Auditory perceptual ratings, and acoustic and aerodynamic assessments were performed before and after treatment. Participants also completed the voice-related quality of life questionnaire before and after the treatment.Result: After 3 weeks of intensive voice therapy, significant improvements were demonstrated in acoustic, aerodynamic, and auditory perceptual parameters, as well as patient perceptions of voice-related quality of life. Acoustically, it was found there were significant decreases in shimmer (p = 0.019), noise-to-harmonic ratio (p = 0.016), and smoothed cepstral peak prominence (p = 0.001). Perceptually, the clients with presbyphonia showed significant reductions in the ratings of the overall grade, roughness, asthenia, and strain. Moreover, there was a significant increase in the total score of the Mandarin version of the Voice-Related Quality of Life measure post-therapy.Conclusion: The investigation provides preliminary evidence that people with presbyphonia can improve their vocal function and voice-related quality of life through intensive WRP therapy within a short period of time.

Impact of Using Smartphone While Walking or Standing: A Study Focused on Age and Cognition

BACKGROUND

Using smartphones during a task that requires upright posture is suggested to be detrimental for the overall motor performance. The aim of this study was to determine the role of age and specific aspects of cognitive function on walking and standing tasks in the presence of smartphone use.

METHODS

51 older (36 women) and 50 young (35 women), mean age: 66.5 ± 6.3 and 22.3 ± 1.7 years, respectively, were enrolled in this study. The impact of using a smartphone was assessed during a dynamic (timed up and go, TUG) and a static balance test (performed on a force platform). Multivariate analyses of variance were applied to verify main effects of age, task, estimates of cognitive function and interactions.

RESULTS

Compared to young, older individuals exhibited a poorer performance on the dynamic and on the static test (age effect: p = 0.001 for both variables). Dual-tasking with a smartphone had a negative impact on both groups (task effect: p = 0.001 for both variables). The negative impact, however, was greater in the older group (age × task effect: p = 0.001 for both variables). Executive function and verbal fluency partially explained results of the dynamic and static tests, respectively.

CONCLUSIONS

The negative impact of using a smartphone while performing tasks similar to daily activities is higher in older compared to young people. Subclinical deficits in distinct aspects of cognitive function partially explain the decreased performance when dual-tasking.

Effects of age simulation and age on motor sequence learning: Interaction of age-related cognitive and motor decline

Aging is known to lead to decrements in sensory and cognitive functioning and motor performance. The purpose of the present experiment was twofold: a) We assessed the influence of wearing an age simulation suit on motor sequence learning, cognitive speed tasks and far visual acuity in healthy, younger adults. b) We evaluated the interaction of cognitive aging and declining motor sequence learning in older adults. In a between-subjects design we tested 11 younger adults (M_age = 23.6 years) without the age suit, 12 younger adults wearing the age suit (M_age = 23.2 years), and 23 older adults (M_age = 72.6 years). All participants learned a simple, spatial-temporal movement sequence on two consecutive days, and we assessed perceptual processing speed (Digit Symbol Substitution test and Figural Speed test) and far visual acuity. Wearing an age simulation suit neither affected the learning of the simple motor sequence nor the performance at the cognitive speed tasks in younger adults. However, far visual acuity suffered from wearing the suit. Younger adults with and without the suit showed better motor sequence learning compared to older adults. The significant correlations between the cognitive speed tests and the motor learning performance in older adults indicated that cognitive aging partially explains some of the variance in age-related motor learning deficits.

Does aging amplify the rule-based efficiency effect in action selection?

When it comes to the selection of adequate movements, people may apply varying strategies. Explicit if-then rules, compared to implicit prospective action planning, can facilitate action selection in young healthy adults. But aging alters cognitive processes. It is unknown whether older adults may similarly, profit from a rule-based approach to action selection. To investigate the potential effects of aging, the Rule/Plan Motor Cognition (RPMC) paradigm was applied to three different age groups between 31 and 90 years of age. Participants selected grips either instructed by a rule or by prospective planning. As a function of age, we found a general increase in a strategy-specific advantage as quantified by the difference in reaction time between plan- and rule-based action selection. However, in older age groups, these differences went in both directions: some participants initiated rule-based action selection faster, while for others, plan-based action selection seemed more efficient. The decomposition of reaction times into speed of the decision process, action encoding, and response caution components suggests that rule-based action selection may reduce action encoding demands in all age groups. There appears a tendency for the younger and middle age groups to have a speed advantage in the rule task when it comes to information accumulation for action selection. Thus, one influential factor determining the robustness of the rule-based efficiency effect across the lifespan may be presented by the reduced speed of information uptake. Future studies need to further specify the role of these parameters for efficient action selection.

Effects of virtual body-representation on motor skill learning

Motor learning is often hindered or facilitated by visual information from one's body and its movement. However, it is unclear whether visual representation of the body itself facilitates motor learning. Thus, we tested the effects of virtual body-representation on motor learning through a virtual reality rotary pursuit task. In the task, visual feedback on participants' movements was identical, but virtual body-representation differed by dividing the experimental conditions into three conditions: non-avatar, non-hand avatar, and hand-shaped avatar. We measured the differences in the rate of motor learning, body-ownership, and sense of agency in the three conditions. Although there were no differences in body-ownership and sense of agency between the conditions, the hand-shaped avatar condition was significantly superior to the other conditions in the rate of learning. These findings suggest that visually recognizing one's body shape facilitates motor learning.

Fist-Palm Test (FiPaT): a bedside motor tool to screen for global cognitive status

Objective

The Fist-Palm Test (FiPaT) is a novel non-verbal task to be used at the patient’s bedside for a cognitive functions screening. The aims of this study are to analyze (I) the qualitative and quantitative performance features at FiPaT, (II) the psychometric characteristics of FiPaT, and (III) the correlation between FiPat and traditional cognitive assessments in subjects with normal cognition (NC), Mild Cognitive Impairment-single domain (MCI-sd), and Mild Cognitive Impairment-multiple domain (MCI-md).

Methods

One hundred-thirteen subjects (53M/60F), with a mean age of 66.28 ± 7.22 years and 11.08 ± 4.93 years of education, were recruited and underwent a complete neuropsychological battery and FiPaT.

Results

We found 68 subjects with NC, 31 with MCI-sd, and 14 with MCI-md and a high reliability of the FiPaT (alpha =0.762). The number of FiPaT errors correlated with age and all neuropsychological tests, except for the memory recall test. Subjects with MCI had greater FiPaT errors than subjects with NC. The FiPaT, used with the MOCA test, predicted the presence of MCI, with a variance of 44%.

Conclusion

The FiPaT is an acceptable and reliable non-verbal test, able to screen for global cognitive status, attention, and executive functions, and to predict the MCI. Future studies will validate this initial findings as well as the discriminatory role of the FiPaT in detecting specific types of cognitive impairment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10072-022-06129-1.

When action prediction grows old: An fMRI study

Predicting the unfolding of others' actions (action prediction) is crucial for successfully navigating the social world and interacting efficiently. Age-related changes in this domain have remained largely unexplored, especially for predictions regarding simple gestures and independent of contextual information or motor expertise. Here, we evaluated whether healthy aging impacts the neurophysiological processes recruited to anticipate, from the observation of implied-motion postures, the correct conclusion of simple grasping and pointing actions. A color-discrimination task served as a control condition to assess the specificity of the age-related effects. Older adults showed reduced efficiency in performance that was yet not specific to the action prediction task. Nevertheless, fMRI results revealed task-specific age-related differences: while both groups showed stronger recruitment of the lateral occipito-temporal cortex bilaterally during the action prediction than the control task, the younger participants additionally showed a higher bilateral engagement of parietal regions. Importantly, in both groups, the recruitment of visuo-motor processes in the right posterior parietal cortex was a predictor of good performance. These results support the hypothesis of decreased involvement of sensorimotor processes in cognitive tasks when processing action- and body-related stimuli in healthy aging. These results have implications for social interaction, which requires the fast reading of others' gestures.

Beam width and arm position but not cognitive task affect walking balance in older adults

Detection of changes in dynamic balance could help identify older adults at fall risk. Walking on a narrow beam with its width, cognitive load, and arm position manipulated could be an alternative to current tests. Therefore, we examined additive and interactive effects of beam width, cognitive task (CT), and arm position on dynamic balance during beam walking in older adults. Twenty older adults (69 ± 4y) walked on 6, 8, and 10-cm wide beams (2-cm high, 4-m-long), with and without CT, with three arm positions (free, crossed, akimbo). We determined cognitive errors, distance walked, step speed, root mean square (RMS) of center of mass (COM) displacement and trunk acceleration in the frontal plane. Beam width decrease progressively reduced distance walked and increased trunk acceleration RMS. Step speed decreased on the narrowest beam and with CT. Arm crossing decreased distance walked and step speed. COM displacement RMS and cognitive errors were not affected by any manipulation. In conclusion, distance walked indicated that beam width and arm position, but less so CT, affected dynamic balance, implying that beam walking has the potential to become a test of fall risk. Stability measurements suggested effective trunk adjustments to control COM position and keep dynamic balance during the task.

Role of Catechol-O-methyltransferase Val158Met Polymorphism on Transcranial Direct Current Stimulation in Swallowing

Transcranial direct current stimulation (tDCS) is one of the latest post-stroke dysphagia treatment modalities, and the effect of tDCS is known to be affected by various factors including genetic polymorphisms. However, the role of catechol-O-methyltransferase (COMT) polymorphisms on tDCS in swallowing is unclear. In this prospective pilot study, we aim to explore the effect of tDCS on the swallowing cortex and subsequent swallowing motor function according to COMT polymorphism. Twenty-four healthy participants received either anodal tDCS or sham mode tDCS on the mylohyoid motor cortex at random order, after inhibitory repetitive transcranial magnetic stimulation (rTMS) for preconditioning. The primary outcome was the changes of mylohyoid-motor-evoked potentials (MH-MEP) amplitude in each COMT polymorphism group, from the post-inhibitory rTMS baseline state to immediate, 30, and 60 min after tDCS. The secondary outcomes were the changes in swallowing function. The results showed that COMT Val/Val polymorphism showed improvement across time in the MH-MEP amplitudes and triggering time of swallowing after tDCS, whereas COMT Met carrier group did not show significant changes of MH-MEP or swallowing function across time. This therapeutic response variability of tDCS in the mylohyoid motor system according to COMT polymorphism support the importance of genetic analysis in individualized dysphagia treatment.

The Impact of Parkinson's Disease on General and Specific Motor Aptitudes: A Study of Older Brazilian Adults

This study investigated motor aptitude in older adults with and without Parkinson's disease (PD) to further specify known motor-related changes of PD. We divided 671 older adults (23.5% male; M_age = 69.6, SD = 6.6 years) into a Parkinson's Disease Group (PDG) and a non-Parkinson's Disease Group (NPG) and assessed their general motor aptitude (GMA) and their specific motor aptitudes (in Coordinative, Proprioceptive, and Perceptive domains) using the Motor Scale for Older Adults. We used the chi-squared tests and logistic regression to identify and affirm an associations between PD and motor aptitude, we found that most adults without PD showed normal motor aptitude (GMA: 80.7%; Proprioceptive: 82.3%; Perceptive: 81.4%) except for the Coordinative skills, for which 56.4% of these participants had motor impairment. Most partipants with PD showed motor impairments (GMA: 94.7%; Coordinative: 97.4%; Proprioceptive: 97.4%), except in the Perceptive domain, for which 68.4% of participants with PD showed normal aptitude. There were significant associations between PD and GMA (OR = 127.6), Coordinative motor skills (OR = 48.0), and Proprioceptive skills (OR = 204.4), even after the model was adjusted for gender and age. Our use of the Motor Scale for Older Adults in contrasting groups of older Brazilian adults provides further specificity to the motor aptitude characteristics of older adults with PD.

Brain Activity and Functional Connectivity Patterns Associated With Fast and Slow Motor Sequence Learning in Late Middle Adulthood

The human brain undergoes structural and functional changes across the lifespan. The study of motor sequence learning in elderly subjects is of particularly interest since previous findings in young adults might not replicate during later stages of adulthood. The present functional magnetic resonance imaging (fMRI) study assessed the performance, brain activity and functional connectivity patterns associated with motor sequence learning in late middle adulthood. For this purpose, a total of 25 subjects were evaluated during early stages of learning [i.e., fast learning (FL)]. A subset of these subjects (n = 11) was evaluated after extensive practice of a motor sequence [i.e., slow learning (SL) phase]. As expected, late middle adults improved motor performance from FL to SL. Learning-related brain activity patterns replicated most of the findings reported previously in young subjects except for the lack of hippocampal activity during FL and the involvement of cerebellum during SL. Regarding functional connectivity, precuneus and sensorimotor lobule VI of the cerebellum showed a central role during improvement of novel motor performance. In the sample of subjects evaluated, connectivity between the posterior putamen and parietal and frontal regions was significantly decreased with aging during SL. This age-related connectivity pattern may reflect losses in network efficiency when approaching late adulthood. Altogether, these results may have important applications, for instance, in motor rehabilitation programs.

Effects and Feasibility of a Memory Exergame Training in Older Adults: A Randomized Controlled Trial

Objective: The aim of the study is to assess the feasibility, sustainability, and effectiveness of task-specific memory exergame training on motor-cognitive performance in older adults. Materials and Methods: Fifty older adults (age: 78.8 ± 7.0 years) participated in a randomized controlled trial with a 10-week intervention and 3-month follow-up period. Both the intervention group (IG: n = 29) and control group (CG: n = 21) underwent a once-weekly exercise program, including strength and balance exercises, while the IG performed an additional exergame training, combining dynamic balance with visuospatial memory tasks. Outcome measures were completion time for distinct levels of memory exergame tasks without (condition 1) and with procedural support (condition 2) and (sub)-total game scores documented by a game-specific assessment strategy. Results: Significant improvements in the IG compared with the CG over the intervention period were found for completion times in most of the analyzed levels of condition 1 (P < 0.001-0.047; η_p² = 0.238-0.335) and one level of condition 2 (P < 0.001, η_p² = 0.267), for the subtotal game score of condition 1 (P = 0.002; η_p² = 0.186), and for the total game score (P = 0.005; η_p² = 0.162). Improvements were partially sustained 3 months after training cessation (P = 0.008-0.039, η_p² = 0.095-0.174). Completion rates for initial levels were 86%-98%. No clinical events or safety issues were observed during the training. Conclusion: The study demonstrates that additional memory exergame training effectively, and sustainably, improves performance in complex motor-cognitive tasks involving dynamic balance and visuospatial memory in older adults.

Cognition and motor learning in a Parkinson's disease cohort: importance of recall in episodic memory

Impaired motor learning in individuals with Parkinson's disease is often attributed to deficits in executive function, which serves as an important cognitive process supporting motor learning. However, less is known about the role of other cognitive domains and its association with motor learning in Parkinson's disease. The objective of this study was to investigate the associations between motor learning and multiple domains of cognitive performance in individuals with Parkinson's disease. Twenty-nine participants with Parkinson's disease received comprehensive neuropsychological testing, followed by practice of a bimanual finger sequence task. A retention test of the finger sequence task was completed 24 h later. Hierarchical linear regressions were used to examine the associations between motor learning (acquisition rate and retention) and cognitive performance in five specific cognitive domains, while controlling for age, sex, and years of Parkinson's disease diagnosis. We found that a higher acquisition rate was associated with better episodic memory, specifically better recall in visual episodic memory, in individuals with Parkinson's disease. No significant associations were observed between retention and cognitive performance in any domains. The association between motor acquisition and episodic memory indicates an increased dependency on episodic memory as a potential compensatory cognitive strategy used by individuals with Parkinson's disease during motor learning.

Measuring age differences in executive control using rapid motor decisions in a robotic object hit and avoid task

Age-related declines in executive control are commonly assessed with neuropsychological tests that also rely on sensory and motor processes that are not typically measured in those tasks. It is therefore difficult to isolate the cognitive contributions from sensorimotor contributions to performance impairments. Rapid motor decision-making tasks may also be sensitive to age differences in executive control but allow for the measurement of sensorimotor contributors to task performance. Recently developed object hit (OH) and object hit and avoid (OHA) tasks using a robotic manipulandum are sensitive to motor and cognitive aspects of performance in stroke and Parkinson's disease. However, the impact of healthy aging, and the specific cognitive mechanisms involved in these tasks has not been assessed. We administered the OH and OHA tasks to 77 younger and 59 healthy older adults to evaluate the relative age differences in the perceptual-motor/sensory, movement coordination, and cognitive measures of performance. The Trail Making Test (TMT) Parts A and B were administered to assess the extent to which the cognitive contributors to OHA task performance are associated with executive functioning. After controlling for hand movement speed, age differences were largest for cognitive measures, with smaller differences in perceptual-motor speed and sensory measures, and little differences in bimanual and spatial coordination measures of performance. The cognitive measures were associated with executive functioning measures from the TMT task. These findings provide evidence that rapid motor decision-making tasks are sensitive to age differences in executive control and can isolate the cognitive from the sensorimotor contributions to task performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cortical Engagement Metrics During Reactive Balance Are Associated With Distinct Aspects of Balance Behavior in Older Adults

Heightened reliance on the cerebral cortex for postural stability with aging is well-known, yet the cortical mechanisms for balance control, particularly in relation to balance function, remain unclear. Here we aimed to investigate motor cortical activity in relation to the level of balance challenge presented during reactive balance recovery and identify circuit-specific interactions between motor cortex and prefrontal or somatosensory regions in relation to metrics of balance function that predict fall risk. Using electroencephalography, we assessed motor cortical beta power, and beta coherence during balance reactions to perturbations in older adults. We found that individuals with greater motor cortical beta power evoked following standing balance perturbations demonstrated lower general clinical balance function. Individual older adults demonstrated a wide range of cortical responses during balance reactions at the same perturbation magnitude, showing no group-level change in prefrontal- or somatosensory-motor coherence in response to perturbations. However, older adults with the highest prefrontal-motor coherence during the post-perturbation, but not pre-perturbation, period showed greater cognitive dual-task interference (DTI) and elicited stepping reactions at lower perturbation magnitudes. Our results support motor cortical beta activity as a potential biomarker for individual level of balance challenge and implicate prefrontal-motor cortical networks in distinct aspects of balance control involving response inhibition of reactive stepping in older adults. Cortical network activity during balance may provide a neural target for precision-medicine efforts aimed at fall prevention with aging.

The neuroprotective effects of polyphenols, their role in innate immunity and the interplay with the microbiota

Neurodegenerative disorders, particularly in the elderly population, represent one of the most pressing social and health-care problems in the world. Besides the well-established role of both oxidative stress and inflammation, alterations of the immune response have been found to be closely linked to the development of neurodegenerative diseases. Interestingly, various scientific evidence reported that an altered gut microbiota composition may contribute to the development of neuroinflammatory disorders. This leads to the proposal of the concept of the gut-brain-immune axis. In this scenario, polyphenols play a pivotal role due to their ability to exert neuroprotective, immunomodulatory and microbiota-remodeling activities. In the present review, we summarized the available literature to provide a scientific evidence regarding this neuroprotective and immunomodulatory effects and the interaction with gut microbiota of polyphenols and, the main signaling pathways involved that can explain their potential therapeutic application in neurodegenerative diseases.

A Short-Term Intervention of High-Intensity Exercise and Anodal-tDCS on Motor Learning in Middle-Aged Adults: An RCT

High-intensity exercise has enhanced motor learning in healthy young adults. Anodal-transcranial direct current stimulation (a-tDCS) may optimize these effects. This study aimed to determine the effects of a short-term high-intensity interval exercise intervention either with or without a-tDCS on the learning and retention of a novel motor task in middle-aged adults. Forty-two healthy middle-aged adults (age = 44.6 ± 6.3, female = 76%) were randomized into three groups: exercise and active a-tDCS, exercise and sham a-tDCS, and a non-exercise and sham a-tDCS control. Participants completed a baseline testing session, followed by three intervention sessions 48-h apart. The exercise groups completed 20-min of high-intensity exercise followed by a novel sequential visual isometric pinch task (SVIPT) while receiving 20-min of 1.5 mA a-tDCS, or sham tDCS. The control group completed 20-min of reading before receiving sham a-tDCS during the SVIPT. Learning was assessed by skill change within and between intervention sessions. Participants returned 5–7 days after the final intervention session and performed the SVIPT task to assess retention. All three groups showed evidence of learning on the SVIPT task. Neither group displayed enhanced overall learning or retention when compared to the control group. High-intensity exercise with or without a-tDCS did not improve learning or retention of a novel motor task in middle-aged adults. The methodological framework provides direction for future research to investigate the potential of differing exercise intensity effects on learning and retention.

Tai chi improves psychoemotional state, cognition, and motor learning in older adults during the COVID-19 pandemic

The aim of this study was to determine the effect of a 10-week tai chi intervention on psychoemotional state, cognition, and motor learning in older adults during the COVID-19 pandemic. Participants aged 60–78 years were randomized to either a control group (n = 15) or a tai chi group (n = 15) for a 10-week period. The tai chi group received two, 8-form tai chi classes of 60 min duration per week. Changes in psychoemotional state, cognition, and the learning of fast and accurate reaching movements were assessed. In addition, the potential roles of the autonomic nervous system and brain-derived neurotrophic factor (BDNF) were investigated. Tai chi practice decreased (P < 0.05) perceived stress, whereas no change in autonomic nervous system activity was observed. Improvements in mental switching correlated with decreased depressive symptoms and increased BDNF levels (P < 0.05), whereas improvements in inhibitory control tended to correlate with BDNF levels (P = 0.08). Improvements in visuospatial processing tended to correlate with decreased depressive symptoms (P = 0.07) while improved visuospatial processing correlated with improved motor planning during learning tasks (P < 0.05). This study suggests that tai chi is an effective intervention that can be delivered under pandemic conditions to improve mental and physical function in older adults.

Potential and efficiency of statistical learning closely intertwined with individuals' executive functions: a mathematical modeling study

Statistical learning (SL) is essential in enabling humans to extract probabilistic regularities from the world. The ability to accomplish ultimate learning performance with training (i.e., the potential of learning) has been known to be dissociated with performance improvement per amount of learning time (i.e., the efficiency of learning). Here, we quantified the potential and efficiency of SL separately through mathematical modeling and scrutinized how they were affected by various executive functions. Our results showed that a high potential of SL was associated with poor inhibition and good visuo-spatial working memory, whereas high efficiency of SL was closely related to good inhibition and good set-shifting. We unveiled the distinct characteristics of SL in relation to potential and efficiency and their interaction with executive functions.

Age-related differences in visual encoding and response strategies contribute to spatial memory deficits

Successful navigation requires memorising and recognising the locations of objects across different perspectives. Although these abilities rely on hippocampal functioning, which is susceptible to degeneration in older adults, little is known about the effects of ageing on encoding and response strategies that are used to recognise spatial configurations. To investigate this, we asked young and older participants to encode the locations of objects in a virtual room shown as a picture on a computer screen. Participants were then shown a second picture of the same room taken from the same (0°) or a different perspective (45° or 135°) and had to judge whether the objects occupied the same or different locations. Overall, older adults had greater difficulty with the task than younger adults although the introduction of a perspective shift between encoding and testing impaired performance in both age groups. Diffusion modelling revealed that older adults adopted a more conservative response strategy, while the analysis of gaze patterns showed an age-related shift in visual-encoding strategies with older adults attending to more information when memorising the positions of objects in space. Overall, results suggest that ageing is associated with declines in spatial processing abilities, with older individuals shifting towards a more conservative decision style and relying more on encoding target object positions using room-based cues compared to younger adults, who focus more on encoding the spatial relationships among object clusters.

Regular participation in leisure time activities and high cardiovascular fitness improve motor sequence learning in older adults

INTRODUCTION

Older adults show higher interindividual performance variability during the learning of new motor sequences than younger adults. It is largely unknown what factors contribute to this variability. This study aimed to, first, characterize age differences in motor sequence learning and, second, examine influencing factors for interindividual performance differences.

METHOD

30 young adults (age M = 21.89, SD = 2.08, 20 female) and 29 older adults (age M = 69.55, SD = 3.03, 18 female) participated in the study. Motor sequence learning was assessed with a discrete sequence production (DSP) task, requiring key presses to a sequence of visual stimuli. Three DSP practice phases (á 8 blocks × 16 sequences, two six-element sequences) and two transfer blocks (new untrained sequences) were performed. Older participants conducted the Mini-Mental Status Examination and a visuospatial working-memory task. All participants finished a questionnaire on everyday leisure activities and a cardiovascular fitness test.

RESULTS

Performance speed increased with practice in both groups, but young improved more than older adults (significant Group × Time effect for response time, F(1,5) = 4.353, p = 0.004, [Formula: see text] = 0.071). Accuracy did not change in any age group (non-significant Group × Time effect for error rates, F(1,5) = 2.130, p = 0.091, [Formula: see text] = 0.036). Older adults revealed lower transfer costs for performance speed (significant Time × Group effect, e.g., simple sequence, F(1,2) = 10.511, p = 0.002, [Formula: see text] = 0.156). High participation in leisure time activities (β = - 0.58, p = 0.010, R² = 0.45) and high cardiovascular fitness (β = - 0.49, p = 0.011, R² = 0.45) predicted successful motor sequence learning in older adults.

DISCUSSION

Results confirmed impaired motor learning in older adults. Younger adults seem to show a better implicit knowledge of the practiced sequences compared to older adults. Regular participation in leisure time activities and cardiovascular fitness seem to prevent age-related decline and to facilitate motor sequence performance and motor sequence learning in older adults.

Explaining Individual Differences in Fine Motor Performance and Learning in Older Adults: The Contribution of Muscle Strength and Cardiovascular Fitness

It remains controversial whether aging influences motor learning and whether physiological factors, such as local strength or fitness, are associated with fine motor performance and learning in older adults (OA). OA (n = 51) and young adults (YA, n = 31) performed a short-term motor learning session using a precision grip force modulation task. The rate of improvement of OA compared with YA was steeper with respect to performance variability and temporal precision. Both age groups showed positive transfer during an unpracticed variant of the force modulation task. Local muscle strength (pinch and grip strength) and high cardiovascular fitness positively predicted fine motor performance, whereas initial performance, muscle strength, and motor fitness (heterogeneous motor test battery) negatively predicted rate of improvement. Analyses indicated potentials, but also limits of plasticity for OA.

The Intersection of Physical Function, Cognitive Performance, Aging, and Multiple Sclerosis: A Cross-sectional Comparative Study

OBJECTIVE

To examine the associations between physical function (walking speed and endurance and functional mobility) and cognitive function (information processing speed and verbal memory) in older adults with multiple sclerosis (MS) and healthy controls.

BACKGROUND

Older adults with MS have worse physical and cognitive function than older adults without MS and young and middle-aged adults with MS. To date, little is known about the associations between, or coupling of, physical and cognitive function outcomes in older adults with MS.

METHODS

We administered physical and cognitive function measures to 40 older adults with MS and 40 demographically matched healthy controls. Pearson product moment correlations were used to examine bivariate linear relationships in the overall sample and in the subsamples of (a) older adults with MS and (b) healthy controls. Linear regression analyses were used to examine the independent associations between demographic characteristics and physical and cognitive function variables in the two subsamples.

RESULTS

In the overall sample, all physical function variables were significantly correlated with cognitive function, as measured by information processing speed, and these correlations were mainly due to the subsample of older adults with MS. The linear regression analyses further indicated that information processing speed and years of education consistently explained variance in all physical function variables, beyond the influence of demographic variables, in older adults with MS.

CONCLUSIONS

Physical function and information processing speed are strongly correlated in older adults with MS. Future research should examine underlying neurobehavioral mechanisms associated with physical and cognitive function as well as behavioral strategies for jointly improving these functions in older adults with MS.

Phone messages affect the detection of approaching pedestrians in healthy young and older adults immersed in a virtual community environment

Background

Mobile phones are increasingly associated with accidents while walking. Little is known, however, about the impact of phone messaging on the actual perception of other pedestrians. This study aimed to investigate the extent to which the detection of approaching pedestrians is affected by the sensory modality (text or audio) of phone messages in young vs. older adults.

Methods

Eighteen healthy young (24 ± 2.9 years) and 15 older adults (68 ± 4.2 years) performed a phone message deciphering task, an obstacle detection task, and a dual-task condition combining both tasks. Participants were tested while seated and viewing a virtual subway station (VE) in a helmet mounted display. As they were passively moved within the VE one of three virtual pedestrians randomly approached them from the center (0°), right (+40°) or left (+40°). When present, phone message conditions were delivered at obstacle movement onset and presented either as (1) text messages on the screen of a virtual phone or (2) audio messages delivered through earphones. Participants were instructed to press a joystick button as soon as they detected the approaching virtual pedestrian and to report the message content at the end of the trials.

Results

Young and older participants showed delayed obstacle detection times with vs. without text messages. Older adults further showed reduced accuracy of message report for texts compared to audio messages. In both groups, audio messages yielded no difference in obstacle detection time or accuracy of message report compared to the no message condition.

Conclusions

Findings indicate that text messages prolong the detection of approaching pedestrians, suggesting that they compromise safe ambulation in community environments. Older adults, who show larger deteriorations on the obstacle detection and message deciphering tasks, may be at even greater risk of collision. Audio messages could be a safer alternative for on-the-go communication.

Developmental factors associated with decline in grip strength from midlife to old age: a British birth cohort study

OBJECTIVES

To test whether developmental factors are associated with grip strength trajectories between 53 and 69 years, and operate independently or on the same pathway/s as adult factors.

DESIGN

British birth cohort study.

SETTING

England, Scotland and Wales.

PARTICIPANTS

3058 men and women.

MAIN OUTCOME MEASURES

Grip strength (kg) at ages 53, 60-64 and 69 were analysed using multilevel models to estimate associations with developmental factors (birth weight, growth parameters, motor and cognitive development) and father's social class, and investigate adult factors that could explain observed associations, testing for age and sex interactions.

RESULTS

In men, heavier birth weight, beginning to walk 'on time', later puberty and greater weight 0-26 years and in women, heavier birth weight and earlier age at first standing were independently associated with stronger grip but not with its decline. The slower decline in grip strength (by 0.07 kg/year, 95% CI 0.02 to 0.11 per 1 SD, p=0.003) in men of higher cognitive ability was attenuated by adjusting for adult verbal memory.

CONCLUSIONS

Patterns of growth and motor development have persisting associations with grip strength between midlife and old age. The strengthening associations with cognition suggest that, at older ages, grip strength increasingly reflects neural ageing processes. Interventions across life that promote muscle development or maintain muscle strength should increase the chance of an independent old age.

Remote Limb Ischemic Conditioning and Motor Learning: Evaluation of Factors Influencing Response in Older Adults

Remote limb ischemic conditioning (RLIC) is a clinically feasible method of promoting tissue protection against subsequent ischemic insult. Recent findings from our lab demonstrated that RLIC robustly enhances motor learning in young, healthy humans. The next step is to determine which individuals would receive maximum benefit from RLIC before applying these findings to clinical rehabilitation populations such as stroke. Numerous factors, such as age, sex, body mass index (BMI), and cardiovascular comorbidities may influence the response. Sixty-nine participants aged 40-80 were randomized to receive either RLIC (n = 33) or sham (n = 36) conditioning. Participants underwent seven consecutive sessions consisting of RLIC or sham conditioning with a blood pressure cuff on the upper extremity and motor training on a stability platform balance task, with two follow-up sessions. Balance change (post-test-pre-test) was compared across participants, groups, and the factors of age, sex, BMI, and comorbidities. Participants in both groups improved their performance on the balance task from pre- to post-test. Overall balance change was independently associated with age and BMI. There was no difference in balance change between RLIC and Sham groups. However, RLIC significantly enhanced balance performance in participants with no comorbidities. Compared with our previous study in young adults, middle-aged and older adults demonstrated smaller improvements on the balance task. RLIC enhanced learning in middle-aged and older adults only in the absence of pre-defined comorbidities. RLIC may be a promising tool for enhancing motor recovery, but the accumulation of comorbidity with age may decrease its effectiveness.

Erasure of striatal chondroitin sulfate proteoglycan-associated extracellular matrix rescues aging-dependent decline of motor learning

Cognitive decline is a feature of aging. Accumulating evidence suggests that the brain extracellular matrix (ECM) is involved in the process of aging-dependent cognitive impairment and neurodegeneration by regulating synaptic neurotransmission and affecting neuroplasticity. Age-related changes in brain structure and cognition are not uniform across the whole brain. Being one of the most vulnerable brain regions to aging-dependent alterations, striatum is integral to several central nervous system functions, such as motor, cognition, and affective control. However, the striatal ECM is largely understudied. We first describe 2 major types of chondroitin sulfate proteoglycan (CSPG)-associated ECM in striatum: perineuronal nets and diffusive ECM. Both types of ECM accumulate in an aging-dependent manner. The accumulation of CSPG-associated ECM correlates with aging-dependent decline in striatum-related cognitive functions, including motor learning and working memory. Enzymatic depletion of CSPG-associated ECM in aged mice via chondroitinase ABC significantly improves motor learning, suggesting that changes in neural ECM CSPGs regulate striatal plasticity. Our study provides a greater understanding of the role of neural ECM underlying striatal plasticity, which is an important precursor to design appropriate therapeutic strategies for normal and pathologic aging.

Learning new gait patterns: Age-related differences in skill acquisition and interlimb transfer

Evidence from upper-extremity literature suggests that the normal ageing process affects an individual's ability to learn and retain a motor skill, but spares their ability to transfer the skill to the untrained, opposite limb. While this phenomenon has been well-studied in the upper-extremity, evidence in the lower-extremity is limited. Further, it is unclear to what extent age-related differences in motor learning and transfer are dependent on visual feedback of the motor task. Therefore, the purpose of this study was to examine the effects of ageing on motor learning, retention, and interlimb transfer during walking with and without visual feedback. Forty-four subjects (24 young; 20 older adults) were tested on a treadmill over two consecutive days. On day 1, subjects learned a new gait pattern by performing a foot-trajectory tracking task that necessitated greater hip and knee flexion during the swing phase of the gait. On day 2, subjects repeated the task with their training leg to test retention, then with their untrained leg to test interlimb transfer. Trials without visual feedback were also collected on both days. Results indicated that older adults had reduced ability to learn the task, and also exhibited lower retention and inter-limb transfer. However, these differences were dependent on visual feedback as the groups performed similarly when feedback was removed. The findings provide novel evidence indicating that ageing impairs learning, retention, and transfer of motor skills in the lower-extremity during walking, which may have implications for gait therapy after stroke and other geriatric conditions.

Age-Related Changes in Field Dependence-Independence and Implications for Geriatric Rehabilitation: A Review

Human aging is a dynamic life-long process and an inevitable experience. As the average age of the world's population rises, demands for effective geriatric rehabilitation dramatically increase. An important consideration for enhancing geriatric behavioral interventions is to better understand aging characteristics in perceptual, cognitive, and motor performances. A general shift in cognitive style from field independence to field dependence has been consistently observed during human aging, as older adults show a greater tendency to rely on environmental information, presumably reflecting a neuro-compensatory mechanism of reducing top-down control and relying instead on bottom-up processing. These changes in cognitive style can impact motor skill learning and relearning and, consequently, affect geriatric rehabilitation and behavioral treatments. In this article, we review research related to the cognitive style of field dependence and independence, and its dynamic associations with aging. We also identify implications of cognitive style for geriatric rehabilitation and explore future research.

Visuospatial function predicts one-week motor skill retention in cognitively intact older adults

Motor learning declines with aging, such that older adults retain less motor skill after practice compared to younger adults. However, it remains unclear if these motor learning declines are related to normal cognitive changes associated with aging. The purpose of this study was to examine which cognitive domains would best predict the amount of retention on a motor task one week after training in cognitively intact older adults. Twenty-one adults ages 65-84 years old were assessed with Repeatable Battery for the Assessment of Neuropsychological Status, which assesses five cognitive domains (immediate and delayed memory, visuospatial/constructional, language, and attention). Participants also completed one training session of a functional upper extremity task, and were re-tested one week later. Stepwise regression indicated that the visuospatial domain was the only significant predictor of how much skill participants retained over one week, with a visual perception subtest explaining the most variance. Results from this study support previous work reporting that older adults' capacity for motor learning can be probed with visuospatial tests. These tests may capture the structural or functional health of neural networks critical for skill learning within the aging brain, and provide valuable clinical insight about an individual's unique rehabilitation potential.

People with Dementia Can Learn Compensatory Movement Maneuvers for the Sit-to-Stand Task: A Randomized Controlled Trial

BACKGROUND

A complex motor skill highly relevant to mobility in everyday life (e.g., sit-to-stand [STS] transfer) has not yet been addressed in studies on motor learning in people with dementia (PwD).

OBJECTIVE

To determine whether a dementia-specific motor learning exercise program enables PwD to learn compensatory STS maneuvers commonly taught in geriatric rehabilitation therapy to enhance patients' STS ability.

METHODS

Ninety-seven patients with mild-to-moderate dementia (Mini-Mental State Examination: 21.9±2.9 points) participated in a double-blinded, randomized, placebo-controlled trial with 10-week intervention and 3-month follow-up period. The intervention group (IG, n = 51) underwent a motor learning exercise program on compensatory STS maneuvers specifically designed for PwD. The control group (CG, n = 46) performed a low-intensity motor placebo activity. Primary outcomes were scores of the Assessment of Compensatory Sit-to-stand Maneuvers in People with Dementia (ACSID), which covers the number of recalled and initiated, and of effectively performed compensatory STS maneuvers. Secondary outcomes included temporal and kinematic STS characteristics measured by a body-fixed motion sensor (BFS, DynaPort® Hybrid).

RESULTS

The IG significantly improved in all ACSID scores compared to the CG (p < 0.001). Secondary analysis confirmed learning effects for all BFS-based outcomes (p < 0.001-0.006). Learning gains were sustained during follow-up for most outcomes.

CONCLUSION

People with mild-to-moderate dementia can learn and retain compensatory STS maneuvers in response to a dementia-specific motor learning exercise program. This is the first study that demonstrated preserved motor learning abilities in PwD by using a motor skill highly relevant to everyday life.

Intellectual ability in young adulthood as an antecedent of physical functioning in older age

OBJECTIVES

low cognitive ability is associated with subsequent functional disability. Whether this association extends across adult life has been little studied. The aim of this study was to examine the association between intellectual ability in young adulthood and physical functioning during a 10-year follow-up in older age.

METHODS

three hundred and sixty persons of the Helsinki Birth Cohort Study (HBCS) male members, born between 1934 and 1944 and residing in Finland in 1971, took part in The Finnish Defence Forces Basic Intellectual Ability Test during the first 2 weeks of their military service training between 1952 and 1972. Their physical functioning was assessed twice using the Short Form 36 (SF-36) questionnaire at average ages of 61 and 71 years. A longitudinal path model linking Intellectual Ability Test score to the physical functioning assessments was used to explore the effect of intellectual ability in young adulthood on physical functioning in older age.

RESULTS

after adjustments for age at measurement, childhood socioeconomic status and adult BMI (kg/m(2)), better intellectual ability total and arithmetic and verbal reasoning subtest scores in young adulthood predicted better physical functioning at age 61 years (P values <0.021). Intellectual ability total and arithmetic and verbal reasoning subtest scores in young adulthood had indirect effects on physical functioning at age 71 years (P values <0.022) through better physical functioning at age 61 years. Adjustment for main chronic diseases did not change the results materially.

CONCLUSION

better early-life intellectual ability helps in maintaining better physical functioning in older age.

No Effect of Anodal Transcranial Direct Current Stimulation Over the Motor Cortex on Response-Related ERPs during a Conflict Task

Anodal transcranial direct current stimulation (tDCS) over the motor cortex is considered a potential treatment for motor rehabilitation following stroke and other neurological pathologies. However, both the context under which this stimulation is effective and the underlying mechanisms remain to be determined. In this study, we examined the mechanisms by which anodal tDCS may affect motor performance by recording event-related potentials (ERPs) during a cued go/nogo task after anodal tDCS over dominant primary motor cortex (M1) in young adults (Experiment 1) and both dominant and non-dominant M1 in older adults (Experiment 2). In both experiments, anodal tDCS had no effect on either response time (RT) or response-related ERPs, including the cue-locked contingent negative variation (CNV) and both target-locked and response-locked lateralized readiness potentials (LRP). Bayesian model selection analyses showed that, for all measures, the null effects model was stronger than a model including anodal tDCS vs. sham. We conclude that anodal tDCS has no effect on RT or response-related ERPs during a cued go/nogo task in either young or older adults.

Learning Temporal Statistics for Sensory Predictions in Aging

Predicting future events based on previous knowledge about the environment is critical for successful everyday interactions. Here, we ask which brain regions support our ability to predict the future based on implicit knowledge about the past in young and older age. Combining behavioral and fMRI measurements, we test whether training on structured temporal sequences improves the ability to predict upcoming sensory events; we then compare brain regions involved in learning predictive structures between young and older adults. Our behavioral results demonstrate that exposure to temporal sequences without feedback facilitates the ability of young and older adults to predict the orientation of an upcoming stimulus. Our fMRI results provide evidence for the involvement of corticostriatal regions in learning predictive structures in both young and older learners. In particular, we showed learning-dependent fMRI responses for structured sequences in frontoparietal regions and the striatum (putamen) for young adults. However, for older adults, learning-dependent activations were observed mainly in subcortical (putamen, thalamus) regions but were weaker in frontoparietal regions. Significant correlations of learning-dependent behavioral and fMRI changes in these regions suggest a strong link between brain activations and behavioral improvement rather than general overactivation. Thus, our findings suggest that predicting future events based on knowledge of temporal statistics engages brain regions involved in implicit learning in both young and older adults.

Frontal Lobe Function and Risk of Hip Fracture in Patient With Alzheimer Disease: An Analysis of Linked Data

To determine the association between frontal lobe function and risk of hip fracture in patients with Alzheimer disease (AD).Retrospective cohort study using multicenter hospital-based dementia registry and national health insurance claim data was done. Participants who had available data of neuropsychological test, national health insurance claim, and other covariates were included. A total of 1660 patients with AD were included based on Stroop Test results. A total of 1563 patients with AD were included based on the Controlled Oral Word Association Test (COWAT) results. Hip fracture was measured by validated identification criteria using national health insurance claim data. Frontal lobe function was measured by Stroop Test and COWAT at baseline.After adjusting for potential covariates, including cognitive function in other domains (language, verbal and nonverbal memory, and attention), the Cox proportional hazard regression analysis revealed that risk of a hip fracture was decreased with a hazard ratio (HR) of 0.98 per one point of increase in the Stroop Test (adjusted HR = 0.98, 95% confidence interval [CI]: 0.97-1.00) and 0.93 per one point increase in COWAT (adjusted HR = 0.93, 95% CI: 0.88-0.99).The risk of hip fracture in AD patients was associated with baseline frontal lobe function. The result of this research presents evidence of association between frontal lobe function and risk of hip fracture in patients with AD.

Visuospatial working memory training facilitates visually-aided explicit sequence learning

Finger sequence learning requires visuospatial working memory (WM). However, the dynamics between age, WM training, and motor skill acquisition are unclear. Therefore, we examined how visuospatial WM training improves finger movement sequential accuracy in younger (n=26, 21.1±1.37years) and older adults (n=22, 70.6±4.01years). After performing a finger sequence learning exercise and numerical and spatial WM tasks, participants in each age group were randomly assigned to either the experimental (EX) or control (CO) groups. For one hour daily over a 10-day period, the EX group practiced an adaptive n-back spatial task while those in the CO group practiced a non-adaptive version. As a result of WM practice, the EX participants increased their accuracy in the spatial n-back tasks, while accuracy remained unimproved in the numerical n-back tasks. In all groups, reaction times (RT) became shorter in most numerical and spatial n-back tasks. The learners in the EX group - but not in the CO group - showed improvements in their retention of finger sequences. The findings support our hypothesis that computerized visuospatial WM training improves finger sequence learning both in younger and in older adults. We discuss the theoretical implications and clinical relevance of this research for motor learning and functional rehabilitation.

Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study

Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age.

Training the developing brain part II: cognitive considerations for youth instruction and feedback

Growing numbers of youth participating in competitive, organized physical activity have led to a concern for the risk of sports-related injuries during important periods of human development. Recent studies have demonstrated the ability of integrative neuromuscular training (INT) to enhance athletic performance and reduce the risk of sports-related injuries in youth. Successful implementation of INT necessitates instruction from knowledgeable and qualified instructors who understand the unique physical, cognitive, and psychosocial characteristics of the youth to provide appropriate training instruction and feedback. Principles of a classical theory of cognitive development provide a useful context for discussion of developmentally appropriate methods and strategies for INT instruction of youth. INT programs that consider these developmentally appropriate approaches will provide a controlled efficacious environment for youth to improve athletic performance and reduce risk of sports-related injury, thus promoting a healthy active lifestyle beyond an individual's formative years.