Male human motor cortex stimulus-response characteristics are not altered by ageing

Smith, Ashleigh E., Sale, Martin V., Higgins, Ryan D., Wittert, Gary A. and Pitcher, Julia B. (2011) Male human motor cortex stimulus-response characteristics are not altered by ageing. Journal of Applied Physiology, 110 1: 206-212. doi:10.1152/japplphysiol.00403.2010

Author Smith, Ashleigh E.
Sale, Martin V.
Higgins, Ryan D.
Wittert, Gary A.
Pitcher, Julia B.
Title Male human motor cortex stimulus-response characteristics are not altered by ageing
Journal name Journal of Applied Physiology   Check publisher's open access policy
ISSN 8750-7587
Publication date 2011-01-11
Sub-type Article (original research)
DOI 10.1152/japplphysiol.00403.2010
Volume 110
Issue 1
Start page 206
End page 212
Total pages 7
Place of publication Bethesda, MD, United States
Publisher American Physiological Society
Collection year 2012
Language eng
Formatted abstract
Evidence suggests that there are aging-related changes in corticospinal stimulus-response curve characteristics in later life. However, there is also limited evidence that these changes may only be evident in postmenopausal women and not in men. This study compared corticospinal stimulus-response curves from a group of young men [19.8 ± 1.6 yr (range 17-23 yr)] and a group of old men [n = 18, aged 64.1 ± 5.0 yr (range 55-73 yr)]. Transcranial magnetic stimulation (TMS) over the contralateral motor cortex was used to evoke motor potentials at a range of stimulus intensities in the first dorsal interosseous muscle of each hand separately. There was no effect of age group or hemisphere (i.e., left vs. right motor cortex) on motor evoked potential (MEP) amplitude or any other stimulus-response characteristic. MEP variability was strongly modulated by resting motor threshold but not by age. M-wave (but not F-wave) amplitude was reduced in old men, but expressing MEP amplitude as a ratio of M-wave amplitude did not reveal any age-related differences in cortically evoked stimulusresponse characteristics. We conclude that male corticospinal stimulus-response characteristics are not altered by advancing age and that previously reported age-related changes in motor cortical excitability assessed with TMS are likely due to changes inherent in the female participants only. Future studies are warranted to fully elucidate the relationship between, and functional significance of, changes in circulating neuroactive sex hormones and motor function in later life.
Keyword Corticospinal stimulus-response curves
Florey Adelaide
Transcranial Magnetic Stimulation
Male Ageing Study
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Unknown
Additional Notes Published online before print November 2010.

Document type: Journal Article
Sub-type: Article (original research)
Collections: Non HERDC
Queensland Brain Institute Publications
ERA 2012 Admin Only
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 17 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 19 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Fri, 14 Oct 2011, 16:30:52 EST by Dr Martin Sale on behalf of Queensland Brain Institute