Magnified visual feedback exacerbates positional variability in older adults due to altered modulation of the primary agonist muscle
- PMID: 22948735
- PMCID: PMC3631577
- DOI: 10.1007/s00221-012-3219-0
Magnified visual feedback exacerbates positional variability in older adults due to altered modulation of the primary agonist muscle
Abstract
The purpose of this study was to determine whether magnified visual feedback during position-holding contractions exacerbates the age-associated differences in motor output variability due to changes in the neural activation of the agonist muscle in the upper and lower limb. Twelve young (18-35 years) and ten older adults (65-85 years) were instructed to accurately match a target position at 5° of index finger abduction and ankle dorsiflexion while lifting 10 % of their 1 repetition maximum (1RM) load. Position was maintained at three different visual angles (0.1°, 1°, and 4°) that varied across trials. Each trial lasted 25 s and visual feedback of position was removed from 15 to 25 s. Positional error was quantified as the root mean square error (RMSE) of the subject's performance from the target. Positional variability was quantified as the standard deviation of the position data. The neural activation of the first dorsal interosseus and tibialis anterior was measured with surface electromyography (EMG). Older adults were less accurate compared with young adults and the RMSE decreased significantly with an increase in visual gain. As expected, and independent of limb, older adults exhibited significantly greater positional variability compared with young adults that was exacerbated with magnification of visual feedback (1° and 4°). This increase in variability at the highest magnification of visual feedback was predicted by a decrease in power from 12 to 30 Hz of the agonist EMG signal. These findings demonstrate that motor control in older adults is impaired by magnified visual feedback during positional tasks.
Figures






Similar articles
-
Greater amount of visual information exacerbates force control in older adults during constant isometric contractions.Exp Brain Res. 2011 Sep;213(4):351-61. doi: 10.1007/s00221-011-2777-x. Epub 2011 Jul 29. Exp Brain Res. 2011. PMID: 21800256 Free PMC article.
-
Greater amount of visual feedback decreases force variability by reducing force oscillations from 0-1 and 3-7 Hz.Eur J Appl Physiol. 2010 Mar;108(5):935-43. doi: 10.1007/s00421-009-1301-5. Epub 2009 Dec 2. Eur J Appl Physiol. 2010. PMID: 19953262 Free PMC article. Clinical Trial.
-
Modulation of force below 1 Hz: age-associated differences and the effect of magnified visual feedback.PLoS One. 2013;8(2):e55970. doi: 10.1371/journal.pone.0055970. Epub 2013 Feb 11. PLoS One. 2013. PMID: 23409099 Free PMC article.
-
Age-associated impairement in endpoint accuracy of goal-directed contractions performed with two fingers is due to altered activation of the synergistic muscles.Exp Gerontol. 2012 Jul;47(7):519-26. doi: 10.1016/j.exger.2012.04.007. Epub 2012 May 8. Exp Gerontol. 2012. PMID: 22580059
-
Aging and variability of voluntary contractions.Exerc Sport Sci Rev. 2011 Apr;39(2):77-84. doi: 10.1097/JES.0b013e31820b85ab. Exerc Sport Sci Rev. 2011. PMID: 21206281 Free PMC article. Review.
Cited by
-
Force control is related to low-frequency oscillations in force and surface EMG.PLoS One. 2014 Nov 5;9(11):e109202. doi: 10.1371/journal.pone.0109202. eCollection 2014. PLoS One. 2014. PMID: 25372038 Free PMC article.
-
Visual Information Processing in Older Adults: Force Control and Motor Unit Pool Modulation.J Mot Behav. 2024;56(3):330-338. doi: 10.1080/00222895.2023.2298888. Epub 2023 Dec 28. J Mot Behav. 2024. PMID: 38155098 Free PMC article.
-
The Effect of Antagonist Muscle Sensory Input on Force Regulation.PLoS One. 2015 Jul 17;10(7):e0133561. doi: 10.1371/journal.pone.0133561. eCollection 2015. PLoS One. 2015. PMID: 26186590 Free PMC article. Clinical Trial.
-
The modulation of force steadiness by electrical nerve stimulation applied to the wrist extensors differs for young and older adults.Eur J Appl Physiol. 2019 Jan;119(1):301-310. doi: 10.1007/s00421-018-4025-6. Epub 2018 Oct 30. Eur J Appl Physiol. 2019. PMID: 30377779
-
Speed but not amplitude of visual feedback exacerbates force variability in older adults.Exp Brain Res. 2018 Oct;236(10):2563-2571. doi: 10.1007/s00221-018-5317-0. Epub 2018 Jun 23. Exp Brain Res. 2018. PMID: 29936533
References
-
- Addison PS. The illustrated wavelet transform handbook. New York: Taylor & Francis Group; 2002.
-
- Baweja HS, Kwon MH, Glover SQ, Christou EA. Greater amount of visual feedback decreases error but not variability during movements and positional tasks with the finger and foot. San Diego: Society for Neuroscience; 2010b.
Publication types
MeSH terms
Grants and funding
LinkOut - more resources
Full Text Sources
Medical
Research Materials