Dopamine function and the efficiency of human movement. J Cogn Neurosci 2014 Mar;26(3):645-57
Date
10/23/2013Pubmed ID
24144250Pubmed Central ID
PMC4805420DOI
10.1162/jocn_a_00503Scopus ID
2-s2.0-84893423157 (requires institutional sign-in at Scopus site) 36 CitationsAbstract
To sustain successful behavior in dynamic environments, active organisms must be able to learn from the consequences of their actions and predict action outcomes. One of the most important discoveries in systems neuroscience over the last 15 years has been about the key role of the neurotransmitter dopamine in mediating such active behavior. Dopamine cell firing was found to encode differences between the expected and obtained outcomes of actions. Although activity of dopamine cells does not specify movements themselves, a recent study in humans has suggested that tonic levels of dopamine in the dorsal striatum may in part enable normal movement by encoding sensitivity to the energy cost of a movement, providing an implicit "motor motivational" signal for movement. We investigated the motivational hypothesis of dopamine by studying motor performance of patients with Parkinson disease who have marked dopamine depletion in the dorsal striatum and compared their performance with that of elderly healthy adults. All participants performed rapid sequential movements to visual targets associated with different risk and different energy costs, countered or assisted by gravity. In conditions of low energy cost, patients performed surprisingly well, similar to prescriptions of an ideal planner and healthy participants. As energy costs increased, however, performance of patients with Parkinson disease dropped markedly below the prescriptions for action by an ideal planner and below performance of healthy elderly participants. The results indicate that the ability for efficient planning depends on the energy cost of action and that the effect of energy cost on action is mediated by dopamine.
Author List
Gepshtein S, Li X, Snider J, Plank M, Lee D, Poizner HAuthor
Xiaoyan Li PhD Assistant Professor in the Neurology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultAged
Antiparkinson Agents
Biomechanical Phenomena
Corpus Striatum
Costs and Cost Analysis
Dopamine
Humans
Middle Aged
Models, Neurological
Motivation
Motor Activity
Neuropsychological Tests
Parkinson Disease
Physical Exertion
Psychomotor Performance
Reward
Risk
Task Performance and Analysis
Uncertainty