Academic Journal
Phase dependence of transport-aperture coordination variability reveals control strategy of reach-to-grasp movements.
| Title: | Phase dependence of transport-aperture coordination variability reveals control strategy of reach-to-grasp movements. |
|---|---|
| Authors: | Rand, Miya K.1 rand@asu.edu, Shimansky, Y. P.2, Hossain, Abul B. M. I.1, Stelmach, George E.1 |
| Source: | Experimental Brain Research. Nov2010, Vol. 207 Issue 1/2, p49-63. 15p. 2 Charts, 5 Graphs. |
| Subject Terms: | *Brain -- Mathematical models, *Central nervous system diseases, *Brain research, *Mathematical models, *Holes |
| Abstract: | Based on an assumption of movement control optimality in reach-to-grasp movements, we have recently developed a mathematical model of transport-aperture coordination (TAC), according to which the hand-target distance is a function of hand velocity and acceleration, aperture magnitude, and aperture velocity and acceleration (Rand et al. in Exp Brain Res 188:263-274, ). Reach-to-grasp movements were performed by young adults under four different reaching speeds and two different transport distances. The residual error magnitude of fitting the above model to data across different trials and subjects was minimal for the aperture-closure phase, but relatively much greater for the aperture-opening phase, indicating considerable difference in TAC variability between those phases. This study's goal is to identify the main reasons for that difference and obtain insights into the control strategy of reach-to-grasp movements. TAC variability within the aperture-opening phase of a single trial was found minimal, indicating that TAC variability between trials was not due to execution noise, but rather a result of inter-trial and inter-subject variability of motor plan. At the same time, the dependence of the extent of trial-to-trial variability of TAC in that phase on the speed of hand transport was sharply inconsistent with the concept of speed-accuracy trade-off: the lower the speed, the larger the variability. Conversely, the dependence of the extent of TAC variability in the aperture-closure phase on hand transport speed was consistent with that concept. Taking into account recent evidence that the cost of neural information processing is substantial for movement planning, the dependence of TAC variability in the aperture-opening phase on task performance conditions suggests that it is not the movement time that the CNS saves in that phase, but the cost of neuro-computational resources and metabolic energy required for TAC regulation in that phase. Thus, the CNS performs a trade-off between that cost and TAC regulation accuracy. It is further discussed that such trade-off is possible because, due to a special control law that governs optimal switching from aperture opening to aperture closure, the inter-trial variability of the end of aperture opening does not affect the high accuracy of TAC regulation in the subsequent aperture-closure phase. [ABSTRACT FROM AUTHOR] |
| Database: | Academic Search Index |
| FullText | Links: – Type: other Text: Availability: 0 CustomLinks: – Url: https://dx.doi.org/doi:10.1007/s00221-010-2428-7 Name: EDS - Springer Nature Journals (s7799221) Category: fullText Text: View record at Springer |
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| Header | DbId: asx DbLabel: Academic Search Index An: 54618689 RelevancyScore: 1204 AccessLevel: 6 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 1203.78198242188 |
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| Items | – Name: Title Label: Title Group: Ti Data: Phase dependence of transport-aperture coordination variability reveals control strategy of reach-to-grasp movements. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Rand%2C+Miya+K%2E%22">Rand, Miya K.</searchLink><relatesTo>1</relatesTo><i> rand@asu.edu</i><br /><searchLink fieldCode="AR" term="%22Shimansky%2C+Y%2E+P%2E%22">Shimansky, Y. P.</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Hossain%2C+Abul+B%2E+M%2E+I%2E%22">Hossain, Abul B. M. I.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Stelmach%2C+George+E%2E%22">Stelmach, George E.</searchLink><relatesTo>1</relatesTo> – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22Experimental+Brain+Research%22">Experimental Brain Research</searchLink>. Nov2010, Vol. 207 Issue 1/2, p49-63. 15p. 2 Charts, 5 Graphs. – Name: Subject Label: Subject Terms Group: Su Data: *<searchLink fieldCode="DE" term="%22Brain+--+Mathematical+models%22">Brain -- Mathematical models</searchLink><br />*<searchLink fieldCode="DE" term="%22Central+nervous+system+diseases%22">Central nervous system diseases</searchLink><br />*<searchLink fieldCode="DE" term="%22Brain+research%22">Brain research</searchLink><br />*<searchLink fieldCode="DE" term="%22Mathematical+models%22">Mathematical models</searchLink><br />*<searchLink fieldCode="DE" term="%22Holes%22">Holes</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: Based on an assumption of movement control optimality in reach-to-grasp movements, we have recently developed a mathematical model of transport-aperture coordination (TAC), according to which the hand-target distance is a function of hand velocity and acceleration, aperture magnitude, and aperture velocity and acceleration (Rand et al. in Exp Brain Res 188:263-274, ). Reach-to-grasp movements were performed by young adults under four different reaching speeds and two different transport distances. The residual error magnitude of fitting the above model to data across different trials and subjects was minimal for the aperture-closure phase, but relatively much greater for the aperture-opening phase, indicating considerable difference in TAC variability between those phases. This study's goal is to identify the main reasons for that difference and obtain insights into the control strategy of reach-to-grasp movements. TAC variability within the aperture-opening phase of a single trial was found minimal, indicating that TAC variability between trials was not due to execution noise, but rather a result of inter-trial and inter-subject variability of motor plan. At the same time, the dependence of the extent of trial-to-trial variability of TAC in that phase on the speed of hand transport was sharply inconsistent with the concept of speed-accuracy trade-off: the lower the speed, the larger the variability. Conversely, the dependence of the extent of TAC variability in the aperture-closure phase on hand transport speed was consistent with that concept. Taking into account recent evidence that the cost of neural information processing is substantial for movement planning, the dependence of TAC variability in the aperture-opening phase on task performance conditions suggests that it is not the movement time that the CNS saves in that phase, but the cost of neuro-computational resources and metabolic energy required for TAC regulation in that phase. Thus, the CNS performs a trade-off between that cost and TAC regulation accuracy. It is further discussed that such trade-off is possible because, due to a special control law that governs optimal switching from aperture opening to aperture closure, the inter-trial variability of the end of aperture opening does not affect the high accuracy of TAC regulation in the subsequent aperture-closure phase. [ABSTRACT FROM AUTHOR] |
| PLink | https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=asx&AN=54618689 |
| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1007/s00221-010-2428-7 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 15 StartPage: 49 Subjects: – SubjectFull: Brain -- Mathematical models Type: general – SubjectFull: Central nervous system diseases Type: general – SubjectFull: Brain research Type: general – SubjectFull: Mathematical models Type: general – SubjectFull: Holes Type: general Titles: – TitleFull: Phase dependence of transport-aperture coordination variability reveals control strategy of reach-to-grasp movements. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Rand, Miya K. – PersonEntity: Name: NameFull: Shimansky, Y. P. – PersonEntity: Name: NameFull: Hossain, Abul B. M. I. – PersonEntity: Name: NameFull: Stelmach, George E. IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 11 Text: Nov2010 Type: published Y: 2010 Identifiers: – Type: issn-print Value: 00144819 Numbering: – Type: volume Value: 207 – Type: issue Value: 1/2 Titles: – TitleFull: Experimental Brain Research Type: main |
| ResultId | 1 |