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Ananda Sidarta
Ph.D. Student
Ph.D. Neuroscience, McGill University, Montreal
M.Sc. Biomedical Engineering, Nanyang Technological University, Singapore
BEng. Electrical & Electronic Engineering, Nanyang Technological University, Singapore
Tel.: +1-514-398-6111
Email: ananda.sidarta@mail.mcgill.ca
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Journal
Articles
Sidarta A, Vahdat S, Bernardi NF, Ostry DJ (2016) Somatic and reinforcement-based plasticity in the initial
stages of human motor learning. J Neurosci. 36:11682-11692.
Abstract PDF
As one learns to dance or play tennis, the desired somatosensory state is typically unknown. Trial and error is important as motor
behavior is shaped by successful and unsuccessful movements. As an experimental model, we designed a task in which human participants
make reaching movements to a hidden target and receive positive reinforcement when successful. We identified somatic and
reinforcement-based sources of plasticity on the basis of changes in functional connectivity using resting-state fMRI before and after
learning. The neuroimaging data revealed reinforcement-related changes in both motor and somatosensory brain areas in which a
strengthening of connectivity was related to the amount of positive reinforcement during learning. Areas of prefrontal cortex were
similarly altered in relation to reinforcement, with connectivity between sensorimotor areas of putamen and the reward-related ventromedial
prefrontal cortex strengthened in relation to the amount of successful feedback received. In other analyses, we assessed connectivity
related to changes in movement direction between trials, a type of variability that presumably reflects exploratory strategies during
learning. We found that connectivity in a network linking motor and somatosensory cortices increased with trial-to-trial changes in
direction. Connectivity varied as well with the change in movement direction following incorrect movements. Here the changes were
observed in a somatic memory and decision making network involving ventrolateral prefrontal cortex and second somatosensory cortex.
Our results point to the idea that the initial stages of motor learning are not wholly motor but rather involve plasticity in somatic and
prefrontal networks related both to reward and exploration.
WT Latt, Tan UX, Georgiou A, Sidarta AE, Riviere CN, Ang WT (2011). "A micro motion sensing system for micromanipulation tasks", Journal of Sensors and Actuators: Physical, Vol. 173, pp 254 - 266.
Abstract PDF
Conference
presentations / published abstracts
Sidarta A., Bergeron K., VanVugt FT, Ostry DJ (2018). "The relationship between somatosensory working memory and human motor learning". Abstract for Neural Control of Movement 2018 - Sante Fe (US).
Sidarta A., VanVugt FT., Bernardi N., Ostry DJ (2017). "Relation of kinaesthetic working memory to human motor learning". Abstract for Society for Neuroscience 2017 - Washington DC (US).
Sidarta A., Vahdat S., Bernardi N., Ostry DJ (2016). "The incentive of success: Plasticity in the initial stages of motor learning". Abstract for the 1st NeuroSymposium - Quebec 2016.
Sidarta A., Bernardi N., Vahdat S., Ostry DJ (2015). "Neural substrates of the initial stages of human motor learning". Abstract for Society for Neuroscience 2015 - Chicago (US).
Bernardi NF, Darainy M, Sidarta A, Ostry DJ (2014). "The contribution of somatosensory perceptual learning to human motor skill acquisition." Abstract for Society for Neuroscience 2014 - Washington DC (US).
Ananda E.S., W.T. Latt, C.Y. Shee, E.L.M. Su, E. Burdet, T.C. Lim, C.L. Teo, W.T. Ang, "Influence of visual feedback and speed on micro-manipulation accuracy", Proc. 31st Ann. Intl. Conf. IEEE Engineering in Medicine and Biology Society - Minneapolis (US), September 2009.
W. T. Latt, U. X. Tan, Ananda E. S., S. C. L. Ong, K. C. Veluvolu, C. Y. Shee, and W. T. Ang, "Design and Implementation of a Two Degrees-of-Freedom Micro-manipulation Assessment System", Proc. 30th Ann. Intl. Conf. IEEE Engineering in Medicine and Biology Society - Vancouver (Canada), August 2008.
