The influence of normal aging on the cortical processing of a simple motor task.
OBJECTIVE
To assess the influence of normal aging on the cortical physiology of motor behavior.


METHODS
The authors studied cortical activation in eight elderly (55 to 76 years of age) and eight younger (18 to 27 years of age) healthy subjects while they performed a simple motor task. A 28-channel EEG was recorded; task-related power changes associated with repetitive, metronome-paced (1 Hz) finger movements were computed as a measure of cortical activation.


RESULTS
Distinct, age-dependent activation patterns were expressed in four distinct frequency ranges: low-alpha (10 to 11 Hz), high-alpha (12 to 13 Hz), low-beta (16 to 17 Hz), and high-beta (22 to 23 Hz) bands. The main findings were a greater overall activation and, more specifically, a pronounced bilateral activation of sensorimotor regions in elderly subjects for both alpha bands. Additionally, in the elderly subjects there was increased activation of the mesial frontocentral cortex (supplementary motor area region) in the high-beta band, whereas younger volunteers had a prominent activation of the left lateral premotor and sensorimotor region in this frequency range.


CONCLUSIONS
These findings demonstrate that the functional anatomy of the human motor system changes during normal aging. It appears that, for a given motor task, the aging brain recruits additional primary sensorimotor and premotor regions of both hemispheres.
Sailer
A
A
Department of Neurology, Tuebingen University, Germany.
Dichgans
J
J
Gerloff
C
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D012016:Reference Values; D013647:Task Performance and Analysis