Early life experience sets hard limits on motor learning as evidenced from artificial arm use
- University of Oxford, United Kingdom
- University College London, United Kingdom
- Nuffield Orthopaedic Centre, United Kingdom
- Imperial College London, United Kingdom
Abstract
The study of artificial arms provides a unique opportunity to address long-standing questions on sensorimotor plasticity and development. Learning to use an artificial arm arguably depends on fundamental building blocks of body representation and would therefore be impacted by early-life experience. We tested artificial arm motor-control in two adult populations with upper-limb deficiencies: a congenital group - individuals who were born with a partial arm, and an acquired group - who lost their arm following amputation in adulthood. Brain plasticity research teaches us that the earlier we train to acquire new skills (or use a new technology) the better we benefit from this practice as adults. Instead, we found that although the congenital group started using an artificial arm as toddlers, they produced increased error noise and directional errors when reaching to visual targets, relative to the acquired group who performed similarly to controls. However, the earlier an individual with a congenital limb difference was fitted with an artificial arm, the better their motor control was. Since we found no group differences when reaching without visual feedback, we suggest that the ability to perform efficient visual-based corrective movements is highly dependent on either biological or artificial arm experience at a very young age. Subsequently, opportunities for sensorimotor plasticity become more limited.
Data availability
All data generated and analysed during this study can be found at https://osf.io/quyke/
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Artificial-arm (prosthesis) motor controlOpen Science Framework, DOI 10.17605/OSF.IO/QUYKE.
Article and author information
Author details
Funding
H2020 European Research Council (715022 EmbodiedTech)
- Tamar R Makin
Wellcome Trust (Senior Research Fellowship (215575/Z/19/Z))
- Tamar R Makin
Clarendon Fund (Graduate Student fellowship)
- Roni O Maimon-Mor
University College, Oxford (Graduate Student fellowship)
- Roni O Maimon-Mor
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Participants were recruited to the study between October 2017 and December 2018, based on the guidelines in our ethical approvals (UCL REC: 9937/001; NHS National Research Ethics service: 18/LO/0474), and in accordance with the declaration of Helsinki. All participants gave full written informed consent for their participation, data storage and dissemination.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Early life experience sets hard limits on motor learning as evidenced from artificial arm use
eLife 10:e66320.
https://doi.org/10.7554/eLife.66320
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