Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements
Multiple proprioceptive signals, like those from muscle spindles, are thought to enable robust estimates of body configuration. Yet, it remains unknown whether spindle signals suffice to discriminate limb movements. Here, a simulated 4-musculotendon, 2-joint planar limb model produced repeated cycle...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2023-06-01
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| Series: | Frontiers in Physiology |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fphys.2023.1183492/full |
| _version_ | 1797791593955065856 |
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| author | Jasmine A. Berry Ali Marjaninejad Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas |
| author_facet | Jasmine A. Berry Ali Marjaninejad Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas |
| author_sort | Jasmine A. Berry |
| collection | DOAJ |
| description | Multiple proprioceptive signals, like those from muscle spindles, are thought to enable robust estimates of body configuration. Yet, it remains unknown whether spindle signals suffice to discriminate limb movements. Here, a simulated 4-musculotendon, 2-joint planar limb model produced repeated cycles of five end-point trajectories in forward and reverse directions, which generated spindle Ia and II afferent signals (proprioceptors for velocity and length, respectively) from each musculotendon. We find that cross-correlation of the 8D time series of raw firing rates (four Ia, four II) cannot discriminate among most movement pairs (∼ 29% accuracy). However, projecting these signals onto their 1st and 2nd principal components greatly improves discriminability of movement pairs (82% accuracy). We conclude that high-dimensional ensembles of muscle proprioceptors can discriminate among limb movements—but only after dimensionality reduction. This may explain the pre-processing of some afferent signals before arriving at the somatosensory cortex, such as processing of cutaneous signals at the cat’s cuneate nucleus. |
| first_indexed | 2024-03-13T02:21:00Z |
| format | Article |
| id | doaj.art-76e4bd052fef4463938683ef7a4b32d7 |
| institution | Directory Open Access Journal |
| issn | 1664-042X |
| language | English |
| last_indexed | 2024-03-13T02:21:00Z |
| publishDate | 2023-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Physiology |
| spelling | doaj.art-76e4bd052fef4463938683ef7a4b32d72023-06-30T09:25:46ZengFrontiers Media S.A.Frontiers in Physiology1664-042X2023-06-011410.3389/fphys.2023.11834921183492Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movementsJasmine A. Berry0Ali Marjaninejad1Francisco J. Valero-Cuevas2Francisco J. Valero-Cuevas3Francisco J. Valero-Cuevas4Brain-Body Dynamics Lab, Department of Computer Science, University of Southern California, Los Angeles, CA, United StatesDepartment of Biomedical Engineering, University of Southern California, Los Angeles, CA, United StatesBrain-Body Dynamics Lab, Department of Computer Science, University of Southern California, Los Angeles, CA, United StatesDepartment of Biomedical Engineering, University of Southern California, Los Angeles, CA, United StatesDivision of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, United StatesMultiple proprioceptive signals, like those from muscle spindles, are thought to enable robust estimates of body configuration. Yet, it remains unknown whether spindle signals suffice to discriminate limb movements. Here, a simulated 4-musculotendon, 2-joint planar limb model produced repeated cycles of five end-point trajectories in forward and reverse directions, which generated spindle Ia and II afferent signals (proprioceptors for velocity and length, respectively) from each musculotendon. We find that cross-correlation of the 8D time series of raw firing rates (four Ia, four II) cannot discriminate among most movement pairs (∼ 29% accuracy). However, projecting these signals onto their 1st and 2nd principal components greatly improves discriminability of movement pairs (82% accuracy). We conclude that high-dimensional ensembles of muscle proprioceptors can discriminate among limb movements—but only after dimensionality reduction. This may explain the pre-processing of some afferent signals before arriving at the somatosensory cortex, such as processing of cutaneous signals at the cat’s cuneate nucleus.https://www.frontiersin.org/articles/10.3389/fphys.2023.1183492/fullmuscle spindle afferentproprioceptionlimb movementtask discriminationdimensionality reductionmusculotendon |
| spellingShingle | Jasmine A. Berry Ali Marjaninejad Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas Francisco J. Valero-Cuevas Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements Frontiers in Physiology muscle spindle afferent proprioception limb movement task discrimination dimensionality reduction musculotendon |
| title | Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements |
| title_full | Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements |
| title_fullStr | Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements |
| title_full_unstemmed | Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements |
| title_short | Edge Computing in Nature: Minimal pre-processing of multi-muscle ensembles of spindle signals improves discriminability of limb movements |
| title_sort | edge computing in nature minimal pre processing of multi muscle ensembles of spindle signals improves discriminability of limb movements |
| topic | muscle spindle afferent proprioception limb movement task discrimination dimensionality reduction musculotendon |
| url | https://www.frontiersin.org/articles/10.3389/fphys.2023.1183492/full |
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