Dopaminergic influences on formation of a motor memory.
The ability of the central nervous system to form motor memories, a process contributing to motor learning and skill acquisition, decreases with age. Dopaminergic activity, one of the mechanisms implicated in memory formation, experiences a similar decline with aging. It is possible that restoring dopaminergic function in elderly adults could lead to improved formation of motor memories with training. We studied the influence of a single oral dose of levodopa (100mg) administered preceding training on the ability to encode an elementary motor memory in the primary motor cortex of elderly and young healthy volunteers in a randomized, double-blind, placebo-controlled design. Attention to the task and motor training kinematics were comparable across age groups and sessions. In young subjects, encoding a motor memory under placebo was more prominent than in older subjects, and the encoding process was accelerated by intake of levodopa. In the elderly group, diminished motor memory encoding under placebo was enhanced by intake of levodopa to levels present in younger subjects. Therefore, upregulation of dopaminergic activity accelerated memory formation in young subjects and restored the ability to form a motor memory in elderly subjects; possible mechanisms underlying the beneficial effects of dopaminergic agents on motor learning in neurorehabilitation.
Human Cortical Physiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20817, USA.
Agnes
A
Flöel
Caterina
C
Breitenstein
Friedhelm
F
Hummel
Pablo
P
Celnik
Christian
C
Gingert
Lumy
L
Sawaki
Stefan
S
Knecht
Leonardo G
LG
Cohen
D000328:Adult; D000367:Age Factors; D004298:Dopamine; D015259:Dopamine Agents / Q000494:pharmacology*; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D007980:Levodopa / Q000494:pharmacology*; D008280:Magnetics; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D009044:Motor Cortex / Q000187:drug effects* / Q000502:physiology
D015259:Dopamine Agents; D007980:Levodopa; D004298:Dopamine