Independent representations of ipsilateral and contralateral limbs in primary motor cortex
Several lines of research demonstrate that primary motor cortex (M1) is principally involved in controlling the contralateral side of the body. However, M1 activity has been correlated with both contralateral and ipsilateral limb movements. Why does ipsilaterally-related activity not cause contralat...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2019-10-01
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| Series: | eLife |
| Subjects: | |
| Online Access: | https://elifesciences.org/articles/48190 |
| _version_ | 1811181547285381120 |
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| author | Ethan A Heming Kevin P Cross Tomohiko Takei Douglas J Cook Stephen H Scott |
| author_facet | Ethan A Heming Kevin P Cross Tomohiko Takei Douglas J Cook Stephen H Scott |
| author_sort | Ethan A Heming |
| collection | DOAJ |
| description | Several lines of research demonstrate that primary motor cortex (M1) is principally involved in controlling the contralateral side of the body. However, M1 activity has been correlated with both contralateral and ipsilateral limb movements. Why does ipsilaterally-related activity not cause contralateral motor output? To address this question, we trained monkeys to counter mechanical loads applied to their right and left limbs. We found >50% of M1 neurons had load-related activity for both limbs. Contralateral loads evoked changes in activity ~10ms sooner than ipsilateral loads. We also found corresponding population activities were distinct, with contralateral activity residing in a subspace that was orthogonal to the ipsilateral activity. Thus, neural responses for the contralateral limb can be extracted without interference from the activity for the ipsilateral limb, and vice versa. Our results show that M1 activity unrelated to downstream motor targets can be segregated from activity related to the downstream motor output. |
| first_indexed | 2024-04-11T09:19:24Z |
| format | Article |
| id | doaj.art-82ab4030ba9e4f948b6a17b906172059 |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-11T09:19:24Z |
| publishDate | 2019-10-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-82ab4030ba9e4f948b6a17b9061720592022-12-22T04:32:15ZengeLife Sciences Publications LtdeLife2050-084X2019-10-01810.7554/eLife.48190Independent representations of ipsilateral and contralateral limbs in primary motor cortexEthan A Heming0Kevin P Cross1https://orcid.org/0000-0001-9820-1043Tomohiko Takei2https://orcid.org/0000-0002-6429-5798Douglas J Cook3Stephen H Scott4https://orcid.org/0000-0002-8821-1843Centre for Neuroscience Studies, Queen’s University, Kingston, CanadaCentre for Neuroscience Studies, Queen’s University, Kingston, CanadaCentre for Neuroscience Studies, Queen’s University, Kingston, Canada; Graduate School of Medicine, The Hakubi Center for Advanced Research, Kyoto University, Kyoto, JapanCentre for Neuroscience Studies, Queen’s University, Kingston, Canada; Department of Surgery, Queen’s University, Kingston, Canada; Department of Surgery, Dalhousie University, Halifax, CanadaCentre for Neuroscience Studies, Queen’s University, Kingston, Canada; Department of Medicine, Queen’s University, Kingston, Canada; Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, CanadaSeveral lines of research demonstrate that primary motor cortex (M1) is principally involved in controlling the contralateral side of the body. However, M1 activity has been correlated with both contralateral and ipsilateral limb movements. Why does ipsilaterally-related activity not cause contralateral motor output? To address this question, we trained monkeys to counter mechanical loads applied to their right and left limbs. We found >50% of M1 neurons had load-related activity for both limbs. Contralateral loads evoked changes in activity ~10ms sooner than ipsilateral loads. We also found corresponding population activities were distinct, with contralateral activity residing in a subspace that was orthogonal to the ipsilateral activity. Thus, neural responses for the contralateral limb can be extracted without interference from the activity for the ipsilateral limb, and vice versa. Our results show that M1 activity unrelated to downstream motor targets can be segregated from activity related to the downstream motor output.https://elifesciences.org/articles/48190feedbackpostureneural computationipsilateralbimanualorthogonality |
| spellingShingle | Ethan A Heming Kevin P Cross Tomohiko Takei Douglas J Cook Stephen H Scott Independent representations of ipsilateral and contralateral limbs in primary motor cortex eLife feedback posture neural computation ipsilateral bimanual orthogonality |
| title | Independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| title_full | Independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| title_fullStr | Independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| title_full_unstemmed | Independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| title_short | Independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| title_sort | independent representations of ipsilateral and contralateral limbs in primary motor cortex |
| topic | feedback posture neural computation ipsilateral bimanual orthogonality |
| url | https://elifesciences.org/articles/48190 |
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