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Logue Cook RN, Kern KL, Brown SH. Effectiveness of a home training program on improving pinch force perception in older adults. J Hand Ther 2024:S0894-1130(24)00003-6. [PMID: 38942652 DOI: 10.1016/j.jht.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/07/2023] [Accepted: 02/09/2024] [Indexed: 06/30/2024]
Abstract
BACKGROUND Hand function is reduced with aging which can lead to impairments in the performance of daily activities and eventually loss of independence. The ability to perceive the forces being applied to an object is an important component of hand control that also declines with age. However, the extent to which force perception can be improved through training remains largely unknown. PURPOSE This study evaluated the effectiveness of a home-training program focused on improving force perception in older adults. STUDY DESIGN Quasi-experimental - Uncontrolled trial. METHODS Eleven independent, healthy adults (mean age: 77.2 ± 6.8 years) participated in a home-based sensorimotor hand training program 6 days/week for 6 weeks. Force perception, the primary outcome variable, was measured as the ability to reproduce a pinch force equal to 25% maximum voluntary contraction in the absence of visual feedback using either the ipsilateral remembered or contralateral concurrent (CC) hand. We also measured hand strength, dexterity, tactile acuity, and cognition before and after training. RESULTS After the program was completed, participants showed a 35% reduction in absolute (p < 0.01, confidence interval (CI): [7.3, 33.2], effect sizes (ES): 0.87) and constant (p = 0.05, CI: [0.0, 34.9], ES: 0.79) force matching errors in the CC condition. Improvements in dominant hand dexterity (Purdue pegboard test) (p < 0.05, CI: [0.2, 2.4], ES: 0.60) and tactile sensitivity (JVP thresholds) (p < 0.05, CI: [-1.7, -0.1], ES: 0.94), as well as cognition (Trail Making Test B) (p < 0.05, CI: [-24,1. -1.6], ES: 0.30) were also observed post-training. CONCLUSIONS The results suggest that home-hand training can be an effective way to improve force perception among older adults.
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Affiliation(s)
- Rachel N Logue Cook
- Motor Control Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI USA
| | - Kathy L Kern
- Motor Control Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI USA
| | - Susan H Brown
- Motor Control Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI USA.
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2
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Davidson S, Learman K, Zimmerman E, Rosenfeldt AB, Koop M, Alberts JL. Older adults are impaired in the release of grip force during a force tracking task. Exp Brain Res 2024; 242:665-674. [PMID: 38246931 PMCID: PMC10894767 DOI: 10.1007/s00221-023-06770-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 12/17/2023] [Indexed: 01/23/2024]
Abstract
Age-related changes in force generation have been implicated in declines in older adult manual dexterity. While force generation is a critical aspect of the successful manipulation of objects, the controlled release of force represents the final component of dexterous activities. The impact of advancing age on the release of grip force has received relatively little investigation despite its importance in dexterity. The primary aim of this project was to determine the effects of age on the control of force release during a precision grip tracking task. Young adults (N = 10, 18-28 years) and older adults (N = 10, 57-77 years) completed a ramp-hold-release (0-35% of maximum grip force) force tracking task with their dominant hand. Compared to young adults, older adults were disproportionately less accurate (i.e., less time within target range) and had more error (i.e., greater relative root mean squared error) in the release of force, compared to generation of grip force. There was a significant difference between groups in two-point discrimination of the thumb, which was moderately correlated to force control across all phases of the task. The decline in force release performance associated with advanced age may be a result of sensory deficits and changes in central nervous system circuitry.
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Affiliation(s)
- Sara Davidson
- Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Avenue, ND-20, Cleveland, OH, 44195, USA
- Youngstown State University, Youngstown, OH, USA
| | | | - Eric Zimmerman
- Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Avenue, ND-20, Cleveland, OH, 44195, USA
| | | | - Mandy Koop
- Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Avenue, ND-20, Cleveland, OH, 44195, USA
- Cleveland Clinic, Center for Neurologic Restoration, Cleveland, OH, USA
| | - Jay L Alberts
- Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Avenue, ND-20, Cleveland, OH, 44195, USA.
- Cleveland Clinic, Center for Neurologic Restoration, Cleveland, OH, USA.
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Tomlin KB, Johnson BP, Westlake KP. Age-Related Differences in Motor Skill Transfer with Brief Memory Reactivation. Brain Sci 2024; 14:65. [PMID: 38248280 PMCID: PMC10813682 DOI: 10.3390/brainsci14010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 12/29/2023] [Accepted: 01/04/2024] [Indexed: 01/23/2024] Open
Abstract
Motor memories can be strengthened through online practice and offline consolidation. Offline consolidation involves the stabilization of memory traces in post-practice periods. Following initial consolidation of a motor memory, subsequent practice of the motor skill can lead to reactivation and reconsolidation of the memory trace. The length of motor memory reactivation may influence motor learning outcomes; for example, brief, as opposed to long, practice of a previously learned motor skill appears to optimize intermanual transfer in healthy young adults. However, the influence of aging on reactivation-based motor learning has been scarcely explored. Here, the effects of brief and long motor memory reactivation schedules on the retention and intermanual transfer of a visuomotor tracing task are explored in healthy older adults. Forty older adults practiced a virtual star-tracing task either three ("brief reactivation") or ten ("long reactivation") times per session over a two-week period. Comparison with a previously reported group of younger adults revealed significant age-related differences in the effect of the motor memory reactivation schedule on the intermanual transfer of the motor task. In older adults, unlike younger adults, no significant between-group differences were found by practice condition in the speed, accuracy, or skill of intermanual task transfer. That is, motor task transfer in healthy younger, but not older, adults appears to benefit from brief memory reactivation. These results support the use of age-specific motor training approaches and may inform motor practice scheduling, with possible implications for physical rehabilitation, sport, and music.
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Affiliation(s)
- Kylie B. Tomlin
- Department of Physical Therapy and Rehabilitation Science, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Brian P. Johnson
- Department of Occupational Therapy, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kelly P. Westlake
- Department of Physical Therapy and Rehabilitation Science, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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4
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Xiong Q, Mo J, Yi C, Jiang S, Liu Y. Motor control differs for increasing and decreasing force production during ankle Isometric exercises in children. BMC Sports Sci Med Rehabil 2023; 15:120. [PMID: 37740224 PMCID: PMC10517481 DOI: 10.1186/s13102-023-00727-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 09/07/2023] [Indexed: 09/24/2023]
Abstract
BACKGROUND Performance of the central nervous system (CNS) in increased and decreasing muscle force around the ankle joint is essential for upright tasks of daily living. Previous studies have shown altered CNS control when they decrease force compared with when they increase force in young and older adults. But whether such alteration exists during childhood with incomplete maturation of CNS systems remain unclear. Therefore, this study aimed to evaluate the disparities in intramuscular EMG-EMG coherence, which serve as indicators of corticospinal drive to muscles during ankle isometric increasing and decreasing force generation in children. METHODS We measured intramuscular EMG-EMG coherence activity of the tibialis anterior (TA) and the associated ability to perform isometric efforts at the ankle in 12 typically developing children (mean ± SD age = 5.91±1.37 years) and 12 healthy young adults (mean ± SD age = 23.16±1.52 years). The participants maintained isometric contractions at 20% of their maximal voluntary contractions (MVC) during ankle dorsiflexion to match a triangle trajectory for 7 s, including ramping up in 3.5 s (increasing force phase) and then linearly ramping down to rest in 3.5 s (decreasing force phase). The variability of force control was characterized by the coefficient of variance (CoV) of force output. Intramuscular EMG-EMG coherence from TA in two frequency bands, the beta band (15-30 Hz) and gamma band (30-45) that could reflect the corticospinal drive, were calculated for the comparison. A repeated measures ANOVA with the within-subjects factor of force generation phase (increasing force vs. decreasing force)x between-subjects factor of the group (children and young adults) was used for statistical analysis. RESULTS Regarding the within-subjects difference, our results exhibited significantly higher CoV of force (p < 0.01) and lower EMG-EMG coherence of TA when they decrease force compared with when they increase force in both children and young adult groups. Regarding the between-subjects difference, the CoV of force was significantly higher (p < 0.01) in children compared to young adults, while the EMG-EMG coherence in children showed a significantly lower (p < 0.01) coherence compared with young adults. Furthermore, the EMG-EMG coherence measures were negatively correlated with the CoV of force. CONCLUSIONS The findings suggest that the age-related development would increase the corticospinal drive to TA muscle to deal with ankle isometric dorsiflexion during childhood, which could be also modulated with the force production phases, including increasing and decreasing force.
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Affiliation(s)
- Qiliang Xiong
- Department of Biomedical Engineering, Nanchang Hangkong University, Jiangxi, China.
| | - Jieyi Mo
- Department of Biomedical Engineering, Nanchang Hangkong University, Jiangxi, China
| | - Chen Yi
- Department of Biomedical Engineering, Nanchang Hangkong University, Jiangxi, China
| | - Shaofeng Jiang
- Department of Biomedical Engineering, Nanchang Hangkong University, Jiangxi, China
| | - Yuan Liu
- Department of Rehabilitation, Children's Hospital of Chongqing Medical University, Chongqing, China.
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Raffalt PC, Yentes JM, Freitas SR, Vaz JR. Calculating sample entropy from isometric torque signals: methodological considerations and recommendations. Front Physiol 2023; 14:1173702. [PMID: 37324377 PMCID: PMC10267410 DOI: 10.3389/fphys.2023.1173702] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 05/16/2023] [Indexed: 06/17/2023] Open
Abstract
We investigated the effect of different sampling frequencies, input parameters and observation times for sample entropy (SaEn) calculated on torque data recorded from a submaximal isometric contraction. Forty-six participants performed sustained isometric knee flexion at 20% of their maximal contraction level and torque data was sampled at 1,000 Hz for 180 s. Power spectral analysis was used to determine the appropriate sampling frequency. The time series were downsampled to 750, 500, 250, 100, 50, and 25 Hz to investigate the effect of different sampling frequency. Relative parameter consistency was investigated using combinations of vector lengths of two and three and tolerance limits of 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, and 0.4, and data lengths between 500 and 18,000 data points. The effect of different observations times was evaluated using Bland-Altman plot for observations times between 5 and 90 s. SaEn increased at sampling frequencies below 100 Hz and was unaltered above 250 Hz. In agreement with the power spectral analysis, this advocates for a sampling frequency between 100 and 250 Hz. Relative consistency was observed across the tested parameters and at least 30 s of observation time was required for a valid calculation of SaEn from torque data.
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Affiliation(s)
- Peter C. Raffalt
- Department of Biology, University of Southern Denmark, Odense, Denmark
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jennifer M. Yentes
- Department of Kinesiology & Sport Management, Texas A&M University, College Station, TX, United States
| | - Sandro R. Freitas
- Faculdade de Motricidade Humana, Universidade de Lisboa, Lisboa, Portugal
| | - João R. Vaz
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health & Science, Caparica, Almada, Portugal
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6
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Koyama S, Tatemoto T, Kumazawa N, Tanabe S, Nakagawa Y, Otaka Y. The effect of differences in powered wheelchair joystick shape on subjective and objective operability. APPLIED ERGONOMICS 2023; 107:103920. [PMID: 36306702 DOI: 10.1016/j.apergo.2022.103920] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 09/15/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Various-shaped joysticks steer electric-powered wheelchairs (EPWs); however, an operability evaluation has not been fully conducted. This study evaluated the subjective and objective operability of various-shaped joysticks in 22 younger and 22 older adults. Participants operated an EPW on an experimental course using nine different-shaped joysticks, before ranking each joystick by their operability (1 = best, 9 = worst) as a primary outcome. Movement time (MT) and driving accuracy (DA) were also measured. Despite no significant differences in the primary outcome between joysticks, the I-shaped joystick with rounded tips (neutral grip) was ranked higher than the others. MT did not differ between joysticks, but DA was higher for the thin-columnar I-shaped joystick (pinch grip) than for the U- and T-shaped joysticks (pronated grip). MT and DA scores for young adults were significantly better than those for older adults. Further studies should be conducted to clarify possible factors related to EPW operability.
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Affiliation(s)
- Soichiro Koyama
- Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Japan.
| | - Tsuyoshi Tatemoto
- Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Japan
| | - Nobuhiro Kumazawa
- Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Japan
| | - Shigeo Tanabe
- Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Japan
| | - Yuki Nakagawa
- Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Japan
| | - Yohei Otaka
- Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Japan
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Cai Y, Tian Q, Gross AL, Wang H, E JY, Agrawal Y, Simonsick EM, Ferrucci L, Schrack JA. Motor and Physical Function Impairments as Contributors to Slow Gait Speed and Mobility Difficulty in Middle-Aged and Older Adults. J Gerontol A Biol Sci Med Sci 2022; 77:1620-1628. [PMID: 34984437 PMCID: PMC9373947 DOI: 10.1093/gerona/glac001] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Motor function affects ability to perform daily activities and maintain independence. Yet, the interrelatedness of upper and lower extremity motor impairments and the magnitude of their contribution to slow gait and mobility difficulty are not well investigated. METHODS Participants in the Baltimore Longitudinal Study of Aging (N = 728, aged 50-99) completed motor and physical function tests including grip and knee extension strength, pegboard, finger tapping, standing balance, chair stands, fast-paced 400-m walk, and usual gait speed. Slow gait was defined as usual gait speed <1.0 m/s. Mobility difficulty was defined as self-reported difficulty walking ¼ mile or climbing stairs. Structural equation modeling examined the interrelationships of motor measures and their contributions to slow gait and mobility difficulty, adjusting for demographics and comorbidities. RESULTS Poorer manual dexterity (-0.571 standard deviation [SD] units, p < .001) and lower muscle strength (upper and lower extremity; -0.447 SD units, p = .014) were most strongly associated with slow gait speed, followed by slower chair stand pace (-0.195 SD units, p = .002) and greater lap time variation (0.102 SD units, p = .028). Lower muscle strength (-0.582 SD units, p = .001) was most strongly associated with mobility difficulty, followed by slower chair stand pace (-0.322 SD units, p < .001), slower gait speed (-0.247 SD units, p < .001), and poorer standing balance (-0.190 SD units, p = .043). CONCLUSIONS Components of manual dexterity and strength were the strongest correlates of slow gait and mobility difficulty in mid-to-late life. Longitudinal studies examining relationships between changes in these motor parameters and mobility are needed to elucidate possible causal effects.
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Affiliation(s)
- Yurun Cai
- Address correspondence to: Yurun Cai, PhD, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA. E-mail:
| | - Qu Tian
- Intramural Research Program, National Institute on Aging, Baltimore, Maryland, USA
| | - Alden L Gross
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA,Center on Aging and Health, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Hang Wang
- Center on Aging and Health, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jian-Yu E
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA,Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Yuri Agrawal
- Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Eleanor M Simonsick
- Intramural Research Program, National Institute on Aging, Baltimore, Maryland, USA
| | - Luigi Ferrucci
- Intramural Research Program, National Institute on Aging, Baltimore, Maryland, USA
| | - Jennifer A Schrack
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA,Center on Aging and Health, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
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Goelz C, Mora K, Stroehlein JK, Haase FK, Dellnitz M, Reinsberger C, Vieluf S. Electrophysiological signatures of dedifferentiation differ between fit and less fit older adults. Cogn Neurodyn 2021; 15:847-859. [PMID: 34603546 PMCID: PMC8448815 DOI: 10.1007/s11571-020-09656-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 11/03/2020] [Accepted: 11/27/2020] [Indexed: 11/26/2022] Open
Abstract
Cardiorespiratory fitness was found to influence age-related changes of resting state brain network organization. However, the influence on dedifferentiated involvement of wider and more unspecialized brain regions during task completion is barely understood. We analyzed EEG data recorded during rest and different tasks (sensory, motor, cognitive) with dynamic mode decomposition, which accounts for topological characteristics as well as temporal dynamics of brain networks. As a main feature the dominant spatio-temporal EEG pattern was extracted in multiple frequency bands per participant. To deduce a pattern’s stability, we calculated its proportion of total variance among all activation patterns over time for each task. By comparing fit (N = 15) and less fit older adults (N = 16) characterized by their performance on a 6-min walking test, we found signs of a lower task specificity of the obtained network features for the less fit compared to the fit group. This was indicated by fewer significant differences between tasks in the theta and high beta frequency band in the less fit group. Repeated measures ANOVA revealed that a significantly lower proportion of total variance can be explained by the main pattern in high beta frequency range for the less fit compared to the fit group [F(1,29) = 12.572, p = .001, partial η2 = .300]. Our results indicate that the dedifferentiation in task-related brain activation is lower in fit compared to less fit older adults. Thus, our study supports the idea that cardiorespiratory fitness influences task-related brain network organization in different task domains.
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Affiliation(s)
- Christian Goelz
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany
| | - Karin Mora
- Department of Mathematics, Paderborn University, Paderborn, Germany
| | - Julia Kristin Stroehlein
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany
| | | | - Michael Dellnitz
- Department of Mathematics, Paderborn University, Paderborn, Germany
| | - Claus Reinsberger
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany
| | - Solveig Vieluf
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany
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9
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Strote C, Gölz C, Stroehlein JK, Haase FK, Koester D, Reinsberger C, Vieluf S. Effects of force level and task difficulty on force control performance in elderly people. Exp Brain Res 2020; 238:2179-2188. [PMID: 32661649 PMCID: PMC7496054 DOI: 10.1007/s00221-020-05864-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 06/30/2020] [Indexed: 11/25/2022]
Abstract
As the proportion of people over 60 years of age rises continuously in westernized societies, it becomes increasingly important to better understand aging processes and how to maintain independence in old age. Fine motor tasks are essential in daily living and, therefore, necessary to maintain. This paper extends the existing literature on fine motor control by manipulating the difficulty of a force maintenance task to characterize performance optima for elderly. Thirty-seven elderly (M = 68.00, SD = 4.65) performed a force control task at dynamically varying force levels, i.e. randomly changing every 3 s between 10%, 20%, and 30% of the individual's maximum voluntary contraction (MVC). This task was performed alone or with one or two additional tasks to increase task difficulty. The force control characteristics accuracy, variability, and complexity were analyzed. Lowest variability was observed at 20%. Accuracy and complexity increased with increasing force level. Overall, increased task difficulty had a negative impact on task performance. Results support the assumption, that attention control has a major impact on force control performance in elderly people. We assume different parameters to have their optimum at different force levels, which remain comparably stable when additional tasks are performed. The study contributes to a better understanding of how force control is affected in real-life situations when it is performed simultaneously to other cognitive and sensory active and passive tasks.
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Affiliation(s)
- Caren Strote
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany
| | - Christian Gölz
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany
| | - Julia Kristin Stroehlein
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany
| | | | - Dirk Koester
- Department of Psychology and Sports Science, Bielefeld University, Universitätsstraße 25, Bielefeld, 33615, Germany
- Faculty Business and Management, BSP Business School Berlin, Calandrellistr. 1-9, Berlin, 12247, Germany
| | - Claus Reinsberger
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany
| | - Solveig Vieluf
- Institute of Sports Medicine, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany.
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Rudisch J, Müller K, Kutz DF, Brich L, Sleimen-Malkoun R, Voelcker-Rehage C. How Age, Cognitive Function and Gender Affect Bimanual Force Control. Front Physiol 2020; 11:245. [PMID: 32292353 PMCID: PMC7121519 DOI: 10.3389/fphys.2020.00245] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/02/2020] [Indexed: 02/06/2023] Open
Abstract
Coordinated bimanual control depends on information processing in different intra- and interhemispheric networks that differ with respect to task symmetry and laterality of execution. Aging and age-related cognitive impairments, but also sex can have detrimental effects on connectivity of these networks. We therefore expected effects of age, cognitive function and sex on bimanual force coordination. We furthermore expected these effects to depend on the characteristics of the task (i.e., difficulty and symmetry). 162 right handed participants (19 younger adults [YA], 21–30 years, 9 females; 52 cognitively healthy older adults [HOA], 80–91 years, 32 females; and 91 older adults with mild cognitive impairments [MCI] 80–91 years, 37 females) performed isometric bimanual force control tasks that required following constant or alternating (cyclic sine-wave) targets and varied in symmetry, i.e., (i) constant symmetric, asymmetric [with constant left and alternating right (ii) or vice versa (iii)], (iv) alternating in- and (v) alternating antiphase (both hands alternating with 0° or 180° relative phase, respectively). We analyzed general performance (time on target), bimanual coordination as coupling between hands (linear correlation coefficient) and structure of variability (i.e., complexity measured through detrended fluctuation analysis). Performance and coupling strongly depended on task symmetry and executing hand, with better performance in symmetric tasks and in asymmetric tasks when the left hand produced a constant and the right hand an alternating force. HOA and MCI, compared to YA, showed poorer performance (time on target) and reduced coupling in in- and antiphase tasks. Furthermore, both groups of OA displayed less complex structure in alternating force production tasks, a marker of reduced control. In addition, we found strong sex effects with females displaying reduced coupling during in- and antiphase coordination and less complex variably structure in constant force production. Results of this study revealed strong effects of age, but also sex on bimanual force control. Effects depended strongly on task symmetry and executing hand, possibly due to different requirements in interhemispheric information processing. So far, we found no clear relationship between behavioral markers of bimanual force control and age-related cognitive decline (compared to healthy aging), making further investigation necessary.
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Affiliation(s)
- Julian Rudisch
- Institute of Human Movement Science and Health, Faculty of Behavioral and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany.,Department of Neuromotor Behavior and Exercise, Institute of Sport and Exercise Sciences, University of Muenster, Muenster, Germany
| | - Katrin Müller
- Institute of Human Movement Science and Health, Faculty of Behavioral and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany
| | - Dieter F Kutz
- Institute of Human Movement Science and Health, Faculty of Behavioral and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany.,Department of Neuromotor Behavior and Exercise, Institute of Sport and Exercise Sciences, University of Muenster, Muenster, Germany
| | - Louisa Brich
- Institute of Human Movement Science and Health, Faculty of Behavioral and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany.,Department of Pediatrics, Technical University Munich, Munich, Germany
| | - Rita Sleimen-Malkoun
- CNRS, Institute of Movement Sciences, Aix-Marseille Université, Marseille, France
| | - Claudia Voelcker-Rehage
- Institute of Human Movement Science and Health, Faculty of Behavioral and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany.,Department of Neuromotor Behavior and Exercise, Institute of Sport and Exercise Sciences, University of Muenster, Muenster, Germany
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11
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Müller K, Fröhlich S, Germano AMC, Kondragunta J, Agoitia Hurtado MFDC, Rudisch J, Schmidt D, Hirtz G, Stollmann P, Voelcker-Rehage C. Sensor-based systems for early detection of dementia (SENDA): a study protocol for a prospective cohort sequential study. BMC Neurol 2020; 20:84. [PMID: 32145744 PMCID: PMC7060588 DOI: 10.1186/s12883-020-01666-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/28/2020] [Indexed: 02/06/2023] Open
Abstract
Background Dementia and cognitive decline are serious social and economic burdens. An increase in the population of older people, as well as longer lifespans mean that numbers of dementia cases are exponentially rising. Neuropathological changes associated with dementia are thought to appear before the clinical manifestation of cognitive symptoms, i.e., memory impairments. Further, some older adults (OA) experience cognitive decline before it can be objectively diagnosed. For optimal care of these patients, it is necessary to detect cognitive decline and dementia at an early stage. In this vein, motor, sensory, and neurophysiological declines could be promising factors if found to be present before the onset of cognitive impairment. Hence, the objective of the SENDA study is to develop a multi-dimensional sensor-based instrument that allows early detection of cognitive decline or dementia in OA with the help of cognitive, sensory, motor, and neurophysiological parameters before its clinical manifestation. Methods/design In the cohort sequential study, participants are assigned to one of three study groups depending on their cognitive status: 1. cognitively healthy individuals (CHI), 2. subjectively cognitively impaired persons (SCI), or 3. (possible) mildly cognitively impaired persons (pMCI, MCI). All groups take part in the same cognitive (e.g., executive function tests), motor (e.g., gait analyses, balance tests), sensory (e.g., vibration perception threshold test, proprioception tests), and neurophysiological (e.g., electroencephalograms) measurements. Depending on the time at which participants are included into the study, all measurements are repeated up to four times in intervals of 8 months within 3 years to identify associations with cognitive changes over time. Discussion This study aims to detect possible motor, sensory, neurophysiological, and cognitive predictors to develop an early screening tool for dementia and its pre-stages in OA. Thus, affected persons could receive optimal health care at an earlier time point to maintain their health resources. Trial status The study is ongoing. The recruitment of participants will be continued until May 2020.
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Affiliation(s)
- Katrin Müller
- Department of Sports Psychology (with focus on prevention and rehabilitation), Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Thüringer Weg 11, 09126, Chemnitz, Germany.
| | - Stephanie Fröhlich
- Department of Sports Psychology (with focus on prevention and rehabilitation), Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Thüringer Weg 11, 09126, Chemnitz, Germany
| | - Andresa M C Germano
- Department of Human Locomotion, Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany
| | - Jyothsna Kondragunta
- Department of Digital Signal Processing and Circuit Technology, Faculty of Electrical Engineering and Information Technology, Chemnitz University of Technology, Chemnitz, Germany
| | | | - Julian Rudisch
- Department of Sports Psychology (with focus on prevention and rehabilitation), Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Thüringer Weg 11, 09126, Chemnitz, Germany.,Department of Neuromotor Behavior and Exercise, University of Münster, Münster, Germany
| | - Daniel Schmidt
- Department of Human Locomotion, Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Chemnitz, Germany
| | - Gangolf Hirtz
- Department of Digital Signal Processing and Circuit Technology, Faculty of Electrical Engineering and Information Technology, Chemnitz University of Technology, Chemnitz, Germany
| | - Peter Stollmann
- Department of Analysis, Faculty of Mathematics, Chemnitz University of Technology, Chemnitz, Germany
| | - Claudia Voelcker-Rehage
- Department of Sports Psychology (with focus on prevention and rehabilitation), Institute of Human Movement Science and Health, Faculty of Behavioural and Social Sciences, Chemnitz University of Technology, Thüringer Weg 11, 09126, Chemnitz, Germany.,Department of Neuromotor Behavior and Exercise, University of Münster, Münster, Germany
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12
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Digit Force Controls and Corresponding Brain Activities in Finger Pressing Performance: A Comparison Between Older Adults and Young Individuals. J Aging Phys Act 2020; 28:94-103. [PMID: 31629354 DOI: 10.1123/japa.2018-0252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 05/05/2019] [Accepted: 05/30/2019] [Indexed: 11/18/2022]
Abstract
This study aims toward an investigation and comparison of the digital force control and the brain activities of older adults and young groups during digital pressing tasks. A total of 15 young and 15 older adults were asked to perform force ramp tasks at different force levels with a custom pressing system. Near-infrared spectroscopy was used to collect the brain activities in the prefrontal cortex and primary motor area. The results showed that the force independence and hand function of the older adults were worse than that of the young adults. The cortical activations in the older adults were higher than those in the young group during the tasks. A significant hemodynamic between-group response and mild negative correlations between brain activation and force independence ability were found. Older adults showed poor force independence ability and manual dexterity and required additional brain activity to compensate for the degeneration.
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13
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Explaining Individual Differences in Fine Motor Performance and Learning in Older Adults: The Contribution of Muscle Strength and Cardiovascular Fitness. J Aging Phys Act 2019; 27:725-738. [PMID: 30747569 DOI: 10.1123/japa.2018-0289] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
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.
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14
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Jin Y, Lee J, Kim S, Yoon B. Noninvasive brain stimulation over M1 and DLPFC cortex enhances the learning of bimanual isometric force control. Hum Mov Sci 2019; 66:73-83. [PMID: 30921762 DOI: 10.1016/j.humov.2019.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 11/19/2022]
Abstract
Motor learning plays an important role in upper-limb function and the recovery of lost functionality. This study aimed to investigate the relative impact of transcranial direct current stimulation (tDCS) on learning in relation to the left primary motor cortex (M1) and left dorsolateral prefrontal cortex (DLPFC) during bimanual isometric force-control tasks performed with both hands under different task constraints. In a single-blind cross-over design, 20 right-handed participants were randomly assigned to either the M1 group (n = 10; mean age, 22.90 ± 1.66 years, mean ± standard deviation) or the DLPFC group (n = 10; mean age, 23.20 ± 1.54 years). Each participant received 30 min of tDCS (anodal or sham, applied randomly in two experiments) while performing the bimanual force control tasks. Anodal tDCS of the M1 improved the accuracy of maintenance and rhythmic alteration of force tasks, while anodal tDCS of the DLPFC improved only the maintenance of the force control tasks compared with sham tDCS. Hence, tDCS over the left M1 and DLPFC has a beneficial effect on the learning of bimanual force control.
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Affiliation(s)
- Yan Jin
- Major in Rehabilitation Science, Graduate School, Korea University, Seoul, Republic of Korea
| | - Jaehyuk Lee
- Major in Rehabilitation Science, Graduate School, Korea University, Seoul, Republic of Korea
| | - Sungyong Kim
- Department of Physical Therapy, College of Health Sciences, Korea University, Seoul, Republic of Korea
| | - BumChul Yoon
- Major in Rehabilitation Science, Graduate School, Korea University, Seoul, Republic of Korea; Department of Physical Therapy, College of Health Sciences, Korea University, Seoul, Republic of Korea.
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15
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Gölz C, Voelcker-Rehage C, Mora K, Reuter EM, Godde B, Dellnitz M, Reinsberger C, Vieluf S. Improved Neural Control of Movements Manifests in Expertise-Related Differences in Force Output and Brain Network Dynamics. Front Physiol 2018; 9:1540. [PMID: 30519188 PMCID: PMC6258820 DOI: 10.3389/fphys.2018.01540] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 10/15/2018] [Indexed: 02/05/2023] Open
Abstract
It is well-established that expertise developed through continuous and deliberate practice has the potential to delay age-related decline in fine motor skills. However, less is known about the underlying mechanisms, that is, whether expertise leads to a higher performance level changing the initial status from which age-related decline starts or if expertise-related changes result in qualitatively different motor output and neural processing providing a resource of compensation for age-related changes. Thus, as a first step, this study aims at a better understanding of expertise-related changes in fine motor control with respect to force output and respective electrophysiological correlates. Here, using a multidimensional approach, we investigated fine motor control of experts and novices in precision mechanics during the execution of a dynamic force control task. On the level of force output, we analyzed precision, variability, and complexity. We further used dynamic mode decomposition (DMD) to analyze the electrophysiological correlates of force control to deduce brain network dynamics. Experts’ force output was more precise, less variable, and more complex. Task-related DMD mean mode magnitudes within the α-band at electrodes over sensorimotor relevant areas were reduced in experts, and lower DMD mean mode magnitudes related to the force output in novices. Our results provide evidence for expertise dependent central adaptions with distinct and more complex organization and decentralization of sensorimotor subsystems. Results from our multidimensional approach can be seen as a step forward in understanding expertise-related changes and exploiting their potential as resources for healthy aging.
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Affiliation(s)
- Christian Gölz
- Institute of Sports Medicine, Paderborn University, Paderborn, Germany
| | - Claudia Voelcker-Rehage
- Institute of Human Movement Science and Health, Chemnitz University of Technology, Chemnitz, Germany
| | - Karin Mora
- Department of Mathematics, Paderborn University, Paderborn, Germany
| | - Eva-Maria Reuter
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Ben Godde
- Department of Psychology & Methods, Jacobs University Bremen, Bremen, Germany
| | - Michael Dellnitz
- Department of Mathematics, Paderborn University, Paderborn, Germany
| | - Claus Reinsberger
- Institute of Sports Medicine, Paderborn University, Paderborn, Germany
| | - Solveig Vieluf
- Institute of Sports Medicine, Paderborn University, Paderborn, Germany
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16
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Carment L, Abdellatif A, Lafuente-Lafuente C, Pariel S, Maier MA, Belmin J, Lindberg PG. Manual Dexterity and Aging: A Pilot Study Disentangling Sensorimotor From Cognitive Decline. Front Neurol 2018; 9:910. [PMID: 30420830 PMCID: PMC6215834 DOI: 10.3389/fneur.2018.00910] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/09/2018] [Indexed: 01/04/2023] Open
Abstract
Manual dexterity measures can be useful for early detection of age-related functional decline and for prediction of cognitive decline. However, what aspects of sensorimotor function to assess remains unclear. Manual dexterity markers should be able to separate impairments related to cognitive decline from those related to healthy aging. In this pilot study, we aimed to compare manual dexterity components in patients diagnosed with cognitive decline (mean age: 84 years, N = 11) and in age comparable cognitively intact elderly subjects (mean age: 78 years, N = 11). In order to separate impairments due to healthy aging from deficits due to cognitive decline we also included two groups of healthy young adults (mean age: 26 years, N = 10) and middle-aged adults (mean age: 41 years, N = 8). A comprehensive quantitative evaluation of manual dexterity was performed using three tasks: (i) visuomotor force tracking, (ii) isochronous single finger tapping with auditory cues, and (iii) visuomotor multi-finger tapping. Results showed a highly significant increase in force tracking error with increasing age. Subjects with cognitive decline had increased finger tapping variability and reduced ability to select the correct tapping fingers in the multi-finger tapping task compared to cognitively intact elderly subjects. Cognitively intact elderly subjects and those with cognitive decline had prolonged force release and reduced independence of finger movements compared to young adults and middle-aged adults. The findings suggest two different patterns of impaired manual dexterity: one related to cognitive decline and another related to healthy aging. Manual dexterity tasks requiring updating of performance, in accordance with (temporal or spatial) task rules maintained in short-term memory, are particularly affected in cognitive decline. Conversely, tasks requiring online matching of motor output to sensory cues were affected by age, not by cognitive status. Remarkably, no motor impairments were detected in patients with cognitive decline using clinical scales of hand function. The findings may have consequences for the development of manual dexterity markers of cognitive decline.
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Affiliation(s)
- Loic Carment
- Inserm U894, Université Paris Descartes, Paris, France
| | - Abir Abdellatif
- Plateforme de Recherche Clinique en Gériatrie, Hôpitaux universitaires Pitié-Salpêtrière-Charles Foix, APHP, Ivry-sur-Seine, France
| | - Carmelo Lafuente-Lafuente
- Service de Gériatrie à orientation Cardiologique et Neurologique, Sorbonne Université, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, APHP, Ivry-sur-Seine, France
| | - Sylvie Pariel
- Département de soins ambulatoires, Hôpitaux universitaires Pitié-Salpêtrière-Charles Foix, APHP, Ivry-sur-Seine, France
| | - Marc A Maier
- FR3636 CNRS, Université Paris Descartes, Paris, France.,Department of Life Sciences, Université Paris Diderot, Paris, France
| | - Joël Belmin
- Service de Gériatrie à orientation Cardiologique et Neurologique, Sorbonne Université, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, APHP, Ivry-sur-Seine, France
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17
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Vieluf S, Mora K, Gölz C, Reuter EM, Godde B, Dellnitz M, Reinsberger C, Voelcker-Rehage C. Age- and Expertise-Related Differences of Sensorimotor Network Dynamics during Force Control. Neuroscience 2018; 388:203-213. [DOI: 10.1016/j.neuroscience.2018.07.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/23/2018] [Accepted: 07/14/2018] [Indexed: 10/28/2022]
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18
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Hübner L, Godde B, Voelcker-Rehage C. Older adults reveal enhanced task-related beta power decreases during a force modulation task. Behav Brain Res 2018; 345:104-113. [DOI: 10.1016/j.bbr.2018.02.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/16/2018] [Accepted: 02/20/2018] [Indexed: 10/18/2022]
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19
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Almuklass AM, Feeney DF, Mani D, Hamilton LD, Enoka RM. Peg-manipulation capabilities of middle-aged adults have a greater influence on pegboard times than those of young and old adults. Exp Brain Res 2018; 236:2165-2172. [PMID: 29785485 DOI: 10.1007/s00221-018-5294-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/16/2018] [Indexed: 11/30/2022]
Abstract
Declines in manual dexterity are frequently quantified as the time it takes to complete the grooved pegboard test. The test requires individuals to manipulate 25 pegs, one at a time, by removing them from a well and inserting them into a prescribed hole. The manipulation of each peg involves four phases: selection, transport, insertion, and return. The purpose of our study was to compare the times to complete the four phases of peg manipulation and the forces applied to the pegboard during peg insertion as young, middle-aged, and old adults performed the grooved pegboard test. The relative significance of the peg-manipulation attributes for 30 young (24.0 ± 4.4 years), 15 middle-aged (46.5 ± 6.5 years), and 15 old (70.4 ± 4.0 years) adults was assessed with a multiple-regression analysis. The grooved pegboard test was performed on a force plate. Pegboard times for the old adults (81 ± 17 s) were longer than those for young (56 ± 7 s) and middle-aged (58 ± 11 s) adults. Regression analysis indicated that the explanatory variables for the pegboard times of young (R2 = 0.33) and middle-aged (R2 = 0.78) adults were the times for the peg insertion and return phases, whereas the predictors for old adults (R2 = 0.49) were the times for the peg selection and transport phases. The relative influence of peg-manipulation capabilities on a pegboard test of manual dexterity was greater for middle-aged adults than for young and old adults.
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Affiliation(s)
- Awad M Almuklass
- Department of Integrative Physiology, University of Colorado, Boulder, CO, 80309, USA. .,College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
| | - Daniel F Feeney
- Department of Integrative Physiology, University of Colorado, Boulder, CO, 80309, USA
| | - Diba Mani
- Department of Integrative Physiology, University of Colorado, Boulder, CO, 80309, USA
| | - Landon D Hamilton
- Department of Integrative Physiology, University of Colorado, Boulder, CO, 80309, USA
| | - Roger M Enoka
- Department of Integrative Physiology, University of Colorado, Boulder, CO, 80309, USA
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20
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Mirakhorlo M, Maas H, Veeger HEJ. Increased enslaving in elderly is associated with changes in neural control of the extrinsic finger muscles. Exp Brain Res 2018; 236:1583-1592. [PMID: 29572650 PMCID: PMC5982445 DOI: 10.1007/s00221-018-5219-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 02/24/2018] [Indexed: 11/03/2022]
Abstract
Aging has consequences for hand motor control, among others affecting finger force enslaving during static pressing tasks. The aim of this study was to assess whether the extent of finger force enslaving changes with aging during a task that involves both static and dynamic phases. Ten right-handed young (22-30 years) and ten elderly subjects (67-79 years) were instructed to first exert a constant force (static phase) and then flex their index finger while counteracting constant resistance forces orthogonal to their fingertips (dynamic phase). The other fingers (non-instructed) were held in extension. EMG activities of the flexor digitorum superficialis (FDS) and extensor digitorum (ED) muscles in the regions corresponding to the index, middle and ring fingers together with their forces and position of index finger were measured. In both elderly and young, forces exerted by the non-instructed fingers increased (around 0.6 N for both young and elderly) during isotonic flexion of the index finger, but with a different delay of on average 100 ± 72 ms in elderly and 334 ± 101 ms in young subjects. Results also suggest different responses in activity of FDS and ED muscle regions of the non-instructed fingers to index finger flexion between elderly and young subjects. The enslaving effect was significantly higher in elderly than in young subjects both in the static (12% more) and dynamic (14% more) phases. These differences in enslaving can at least partly be explained by changes in neuromuscular control.
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Affiliation(s)
- M Mirakhorlo
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands.
| | - H Maas
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands
| | - H E J Veeger
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands.,Department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands
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21
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Motor practice in a force modulation task in young and middle-aged adults. J Electromyogr Kinesiol 2018; 38:224-231. [DOI: 10.1016/j.jelekin.2017.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 12/06/2017] [Accepted: 12/21/2017] [Indexed: 11/22/2022] Open
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22
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Hamilton LD, Thomas E, Almuklass AM, Enoka RM. A framework for identifying the adaptations responsible for differences in pegboard times between middle-aged and older adults. Exp Gerontol 2017; 97:9-16. [PMID: 28688836 PMCID: PMC5591777 DOI: 10.1016/j.exger.2017.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/22/2017] [Accepted: 07/03/2017] [Indexed: 11/25/2022]
Abstract
Time to complete two tests of manual dexterity, the 9-hole Peg Test and Grooved Pegboard Test, increases with advancing age. However, the adaptations responsible for the differences in pegboard times between middle-aged and older adults are largely unknown. Potential mechanisms include neuromuscular characteristics, cognitive function, and cutaneous sensation. To provide a tractable framework to address these gaps in knowledge, the purpose of the current study was to identify the latent variables underlying age-associated differences in time to complete the 9-hole and grooved pegboard tests. The approach involved an independent component analysis that identified associations between the two pegboard times for the two groups of participants with two to six secondary outcomes. The common association across three of the four conditions (two groups and two pegboard tests) was features derived from force-matching tasks requiring submaximal isometric contraction. In addition, there were significant associations for older adults between age, measures of cognitive function, and pegboard times. Nonetheless, the significant associations were unique for each age group and pegboard test. The results provide a framework for subsequent mechanistic studies to identify the adaptations underlying age-associated declines in manual dexterity.
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Affiliation(s)
- Landon D Hamilton
- Department of Integrative Physiology, University of Colorado, 354 UCB, Boulder, CO 80309-0354, United States.
| | - Ewan Thomas
- Sports and Exercise Science Research Unit, University of Palermo, Palermo, Italy.
| | - Awad M Almuklass
- Department of Integrative Physiology, University of Colorado, 354 UCB, Boulder, CO 80309-0354, United States.
| | - Roger M Enoka
- Department of Integrative Physiology, University of Colorado, 354 UCB, Boulder, CO 80309-0354, United States; Department of Mathematics, University of Colorado, Boulder, CO.
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23
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Krehbiel LM, Kang N, Cauraugh JH. Age-related differences in bimanual movements: A systematic review and meta-analysis. Exp Gerontol 2017; 98:199-206. [PMID: 28890358 DOI: 10.1016/j.exger.2017.09.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/20/2017] [Accepted: 09/05/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND With increasing age motor functions decline. The additional challenges of executing bimanual movements further hinder motor functions in older adults. The current systematic review and meta-analysis determined the effects of healthy aging on performance in bimanual movements as compared to younger adults. METHODS Our comprehensive search identified 27 studies that reported bimanual movement performance measures. Each study included a between groups comparison of older (mean age=68.79years) and younger adults (mean age=23.14years). The 27 qualified studies generated 40 total outcome measure comparisons: (a) accuracy: 18, (b) variability: 14, and (c) movement time: eight. RESULTS Our meta-analysis conducted on a random effects model identified a relatively large negative standardized mean difference effect (ES=-0.93). This indicates that older adults exhibited more impaired bimanual movement performance in comparison to younger adults in our group of studies. Specifically, a moderator variable analysis revealed large negative effects in both accuracy (ES=-0.94) and variability (ES=-1.00), as well as a moderate negative effect (ES=-0.71) for movement time. These findings indicate that older adults displayed reduced accuracy, greater variability, and longer execution time when executing bimanual movements. CONCLUSION These meta-analytic findings revealed that aging impairs bimanual movement performance.
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Affiliation(s)
- Lisa M Krehbiel
- Motor Behavior Laboratory, University of Florida, Gainesville, Florida, USA
| | - Nyeonju Kang
- Laboratory for Rehabilitation Neuroscience, University of Florida, Gainesville, Florida, USA; Division of Sport Science, Incheon National University, Incheon, South Korea
| | - James H Cauraugh
- Motor Behavior Laboratory, University of Florida, Gainesville, Florida, USA.
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24
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Differences in grip force control between young and late middle-aged adults. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2017; 40:595-602. [PMID: 28831682 DOI: 10.1007/s13246-017-0567-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 06/20/2017] [Indexed: 10/19/2022]
Abstract
Grip force control is a crucial function for human to guarantee the quality of life. To examine the effects of age on grip force control, 10 young adults and 11 late middle-aged adults participated in visually guided tracking tasks using different target force levels (25, 50, and 75% of the subject's maximal grip force). Multiple measures were used to evaluate the tracking performance during force rising phase and force maintenance phase. The measurements include the rise time, fuzzy entropy, mean force percentage, coefficient of variation, and target deviation ratio. The results show that the maximal grip force was significantly lower in the late middle-aged adults than in the young adults. The time of rising phase was systematically longer among late middle-aged adults. The fuzzy entropy is a useful indicator for quantitating the force variability of the grip force signal at higher force levels. These results suggest that the late middle-aged adults applied a compensatory strategy that allow allows for sufficient time to reach the required grip force and reduce the impact of the early and subtle degenerative changes in hand motor function.
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25
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Vieluf S, Sleimen-Malkoun R, Voelcker-Rehage C, Jirsa V, Reuter EM, Godde B, Temprado JJ, Huys R. Dynamical signatures of isometric force control as a function of age, expertise, and task constraints. J Neurophysiol 2017; 118:176-186. [PMID: 28356479 DOI: 10.1152/jn.00691.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 03/10/2017] [Accepted: 03/27/2017] [Indexed: 01/27/2023] Open
Abstract
From the conceptual and methodological framework of the dynamical systems approach, force control results from complex interactions of various subsystems yielding observable behavioral fluctuations, which comprise both deterministic (predictable) and stochastic (noise-like) dynamical components. Here, we investigated these components contributing to the observed variability in force control in groups of participants differing in age and expertise level. To this aim, young (18-25 yr) as well as late middle-aged (55-65 yr) novices and experts (precision mechanics) performed a force maintenance and a force modulation task. Results showed that whereas the amplitude of force variability did not differ across groups in the maintenance tasks, in the modulation task it was higher for late middle-aged novices than for experts and higher for both these groups than for young participants. Within both tasks and for all groups, stochastic fluctuations were lowest where the deterministic influence was smallest. However, although all groups showed similar dynamics underlying force control in the maintenance task, a group effect was found for deterministic and stochastic fluctuations in the modulation task. The latter findings imply that both components were involved in the observed group differences in the variability of force fluctuations in the modulation task. These findings suggest that between groups the general characteristics of the dynamics do not differ in either task and that force control is more affected by age than by expertise. However, expertise seems to counteract some of the age effects.NEW & NOTEWORTHY Stochastic and deterministic dynamical components contribute to force production. Dynamical signatures differ between force maintenance and cyclic force modulation tasks but hardly between age and expertise groups. Differences in both stochastic and deterministic components are associated with group differences in behavioral variability, and observed behavioral variability is more strongly task dependent than person dependent.
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Affiliation(s)
- Solveig Vieluf
- Institute of Sports Medicine, University of Paderborn, Paderborn, Germany.,Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut des Sciences du Mouvement, Marseille, France.,Jacobs Center on Lifelong Learning and Institutional Change, Jacobs University, Bremen, Germany
| | - Rita Sleimen-Malkoun
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut des Sciences du Mouvement, Marseille, France
| | - Claudia Voelcker-Rehage
- Jacobs Center on Lifelong Learning and Institutional Change, Jacobs University, Bremen, Germany.,Institute of Human Movement Science and Health, Chemnitz University of Technology, Chemnitz, Germany
| | - Viktor Jirsa
- Aix Marseille Université, Inserm, INS, Institut de Neurosciences des Systèmes, Marseille, France
| | - Eva-Maria Reuter
- Jacobs Center on Lifelong Learning and Institutional Change, Jacobs University, Bremen, Germany.,Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Ben Godde
- Jacobs Center on Lifelong Learning and Institutional Change, Jacobs University, Bremen, Germany.,Department of Psychology & Methods, Jacobs University Bremen, Bremen, Germany; and
| | - Jean-Jacques Temprado
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut des Sciences du Mouvement, Marseille, France
| | - Raoul Huys
- Université Toulouse III-Paul Sabatier, CNRS, Centre de Recherche Cerveau et Cognition UMR 5549, Toulouse, France
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Yu SH, Huang CY. Improving posture-motor dual-task with a supraposture-focus strategy in young and elderly adults. PLoS One 2017; 12:e0170687. [PMID: 28151943 PMCID: PMC5289460 DOI: 10.1371/journal.pone.0170687] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/09/2017] [Indexed: 11/19/2022] Open
Abstract
In a postural-suprapostural task, appropriate prioritization is necessary to achieve task goals and maintain postural stability. A “posture-first” principle is typically favored by elderly people in order to secure stance stability, but this comes at the cost of reduced suprapostural performance. Using a postural-suprapostural task with a motor suprapostural goal, this study investigated differences between young and older adults in dual-task cost across varying task prioritization paradigms. Eighteen healthy young (mean age: 24.8 ± 5.2 years) and 18 older (mean age: 68.8 ± 3.7 years) adults executed a designated force-matching task from a stabilometer board using either a stabilometer stance (posture-focus strategy) or force-matching (supraposture-focus strategy) as the primary task. The dual-task effect (DTE: % change in dual-task condition; positive value: dual-task benefit, negative value: dual-task cost) of force-matching error and reaction time (RT), posture error, and approximate entropy (ApEn) of stabilometer movement were measured. When using the supraposture-focus strategy, young adults exhibited larger DTE values in each behavioral parameter than when using the posture-focus strategy. The older adults using the supraposture-focus strategy also attained larger DTE values for posture error, stabilometer movement ApEn, and force-matching error than when using the posture-focus strategy. These results suggest that the supraposture-focus strategy exerted an increased dual-task benefit for posture-motor dual-tasking in both healthy young and elderly adults. The present findings imply that the older adults should make use of the supraposture-focus strategy for fall prevention during dual-task execution.
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Affiliation(s)
- Shu-Han Yu
- Physical Therapy Center, National Taiwan University Hospital, Taipei City, Taiwan
| | - Cheng-Ya Huang
- Physical Therapy Center, National Taiwan University Hospital, Taipei City, Taiwan
- School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei City, Taiwan
- * E-mail:
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Vieluf S, Godde B, Reuter EM, Temprado JJ, Voelcker-Rehage C. Practice effects in bimanual force control: does age matter? J Mot Behav 2016; 47:57-72. [PMID: 25575223 DOI: 10.1080/00222895.2014.981499] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The authors examined age-related differences in fine motor control during a bimanual coordination task. The task required the modulation of fingertip forces in the precision grip according to a visually presented sinusoidal antiphase pattern (force range 2-12 N; frequency 0.2 Hz). Thirty-four right-handed participants of three age groups (young, early middle-aged, and late middle-aged) practiced 30 trials of the task. Accuracy and variability of relative timing and relative forces at minima and maxima of the sine wave were analyzed for hand-hand and hand-stimulus couplings and compared between age groups. Analysis showed for relative timing and force weaker hand-hand than hand-stimulus coupling as well as lower accuracy and higher variability for minima as compared to maxima. Further, we analyzed practice effects by comparing the first and last trials and characterized the course of practice by detecting the transition of a steeper to a shallower acquisition slope for the different age groups. Late middle-aged participants demonstrated poorer performance than both other groups for all parameters. All groups improved performance to a similar amount. However, an age-related difference in acquisition strategy is visible. Late middle-aged participants seemed to have focused on improvement of force amplitude, whereas young and early middle-aged focused on timing.
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Affiliation(s)
- Solveig Vieluf
- a Jacobs Center on Lifelong Learning and Institutional Development , Jacobs University Bremen , Germany
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Lee B, Lee M, Yoh MS, You H, Park H, Jung K, Lee BH, Na DL, Kim GH. The Effects of Age, Gender, and Hand on Force Control Capabilities of Healthy Adults. HUMAN FACTORS 2015; 57:1348-1358. [PMID: 26282190 DOI: 10.1177/0018720815599284] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 07/09/2015] [Indexed: 06/04/2023]
Abstract
OBJECTIVE The present study examined the effects of age (20s to 70s), gender (male and female), and hand (dominant and nondominant) on force control capabilities (FCCs) in four force control phases (initiation, development, maintenance, and termination). BACKGROUND Normative data of FCCs by force control phase are needed for various populations in age and gender to identify a type of motor performance reduction and its severity. METHOD FCCs of 360 participants (30 for each combination of age group and gender) were measured using a finger dynamometer and quantified in terms of initiation time (IT), development time (DT), maintenance error (ME), and termination time (TT). RESULTS Although gradual increases (1%~28%) by age were shown in IT, DT, and TT, a dramatic increase in ME was observed among participants in their 50s (26%), 60s (68%), and 70s (160%) compared to those in their 20s~40s. The most distinctive interaction effect of age and gender was found in ME out of the four FCC measures. Lastly, hand and its related interactions were not found significant. CONCLUSION Normative FCC data were established for four age groups (20s~40s, 50s, 60s, and 70s) and gender. APPLICATION The normative FCC data can be used for evaluating an individual's motor performance, screening patients with brain disorders, and designing input devices triggered and/or operated by the finger.
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Affiliation(s)
- Baekhee Lee
- Pohang University of Science and Technology (POSTECH), Pohang, South KoreaLG Electronics, Seoul, South KoreaUniversity of Ulsan, Ulsan, South KoreaSungkyunkwan University School of Medicine, Seoul, South KoreaEwha Womans University Mokdong Hospital, Seoul, South Korea
| | - Mina Lee
- Pohang University of Science and Technology (POSTECH), Pohang, South KoreaLG Electronics, Seoul, South KoreaUniversity of Ulsan, Ulsan, South KoreaSungkyunkwan University School of Medicine, Seoul, South KoreaEwha Womans University Mokdong Hospital, Seoul, South Korea
| | - Myeung Sook Yoh
- Pohang University of Science and Technology (POSTECH), Pohang, South KoreaLG Electronics, Seoul, South KoreaUniversity of Ulsan, Ulsan, South KoreaSungkyunkwan University School of Medicine, Seoul, South KoreaEwha Womans University Mokdong Hospital, Seoul, South Korea
| | - Heecheon You
- Pohang University of Science and Technology (POSTECH), Pohang, South Korea
| | | | | | - Byung Hwa Lee
- Pohang University of Science and Technology (POSTECH), Pohang, South KoreaLG Electronics, Seoul, South KoreaUniversity of Ulsan, Ulsan, South KoreaSungkyunkwan University School of Medicine, Seoul, South KoreaEwha Womans University Mokdong Hospital, Seoul, South Korea
| | - Duk L Na
- Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Geon Ha Kim
- Ewha Womans University Mokdong Hospital, Seoul, South Korea
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Reuter EM, Behrens M, Zschorlich VR. Age-related differences in corticomotor facilitation indicate dedifferentiation in motor planning. Exp Gerontol 2015; 65:79-84. [DOI: 10.1016/j.exger.2015.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 03/11/2015] [Accepted: 03/16/2015] [Indexed: 01/03/2023]
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Vieluf S, Temprado JJ, Berton E, Jirsa VK, Sleimen-Malkoun R. Effects of task and age on the magnitude and structure of force fluctuations: insights into underlying neuro-behavioral processes. BMC Neurosci 2015; 16:12. [PMID: 25887599 PMCID: PMC4359767 DOI: 10.1186/s12868-015-0153-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 02/25/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The present study aimed at characterizing the effects of increasing (relative) force level and aging on isometric force control. To achieve this objective and to infer changes in the underlying control mechanisms, measures of information transmission, as well as magnitude and time-frequency structure of behavioral variability were applied to force-time-series. RESULTS Older adults were found to be weaker, more variable, and less efficient than young participants. As a function of force level, efficiency followed an inverted-U shape in both groups, suggesting a similar organization of the force control system. The time-frequency structure of force output fluctuations was only significantly affected by task conditions. Specifically, a narrower spectral distribution with more long-range correlations and an inverted-U pattern of complexity changes were observed with increasing force level. Although not significant older participants displayed on average a less complex behavior for low and intermediate force levels. The changes in force signal's regularity presented a strong dependence on time-scales, which significantly interacted with age and condition. An inverted-U profile was only observed for the time-scale relevant to the sensorimotor control process. However, in both groups the peak was not aligned with the optimum of efficiency. CONCLUSION Our results support the view that behavioral variability, in terms of magnitude and structure, has a functional meaning and affords non-invasive markers of the adaptations of the sensorimotor control system to various constraints. The measures of efficiency and variability ought to be considered as complementary since they convey specific information on the organization of control processes. The reported weak age effect on variability and complexity measures suggests that the behavioral expression of the loss of complexity hypothesis is not as straightforward as conventionally admitted. However, group differences did not completely vanish, which suggests that age differences can be more or less apparent depending on task properties and whether difficulty is scaled in relative or absolute terms.
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Affiliation(s)
- Solveig Vieluf
- Aix-Marseille Université, CNRS, Institut des Sciences du Mouvement UMR 7287, 13288, Marseille cedex 09, France.
| | - Jean-Jacques Temprado
- Aix-Marseille Université, CNRS, Institut des Sciences du Mouvement UMR 7287, 13288, Marseille cedex 09, France.
| | - Eric Berton
- Aix-Marseille Université, CNRS, Institut des Sciences du Mouvement UMR 7287, 13288, Marseille cedex 09, France.
| | - Viktor K Jirsa
- Aix-Marseille Université, Inserm, Institut de Neurosciences des Systèmes UMR_S 1106, 13385, Marseille, France.
| | - Rita Sleimen-Malkoun
- Aix-Marseille Université, CNRS, Institut des Sciences du Mouvement UMR 7287, 13288, Marseille cedex 09, France.
- Aix-Marseille Université, Inserm, Institut de Neurosciences des Systèmes UMR_S 1106, 13385, Marseille, France.
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Brown SD, Furrow D, Hill DF, Gable JC, Porter LP, Jacobs WJ. A Duty to Describe. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2014; 9:626-40. [DOI: 10.1177/1745691614551749] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Although many researchers have discussed replication as a means to facilitate self-correcting science, in this article, we identify meta-analyses and evaluating the validity of correlational and causal inferences as additional processes crucial to self-correction. We argue that researchers have a duty to describe sampling decisions they make; without such descriptions, self-correction becomes difficult, if not impossible. We developed the Replicability and Meta-Analytic Suitability Inventory (RAMSI) to evaluate the descriptive adequacy of a sample of studies taken from current psychological literature. Authors described only about 30% of the sampling decisions necessary for self-correcting science. We suggest that a modified RAMSI can be used by authors to guide their written reports and by reviewers to inform editorial recommendations. Finally, we claim that when researchers do not describe their sampling decisions, both readers and reviewers may assume that those decisions do not matter to the outcome of the study, do not affect inferences made from the research findings, do not inhibit inclusion in meta-analyses, and do not inhibit replicability of the study. If these assumptions are in error, as they often are, and the neglected decisions are relevant, then the neglect may create a good deal of mischief in the field.
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Vieluf S, Godde B, Reuter EM, Voelcker-Rehage C. Effects of age and fine motor expertise on the bilateral deficit in force initiation. Exp Brain Res 2013; 231:107-16. [DOI: 10.1007/s00221-013-3673-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 08/02/2013] [Indexed: 11/28/2022]
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