Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex
The posterior parietal cortex (PPC) is thought to play an important role in the planning of visually-guided reaching movements. However, the relative roles of the various subdivisions of the PPC in this function are still poorly understood. For example, studies of dorsal area 5 point to a representa...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2013-05-01
|
| Series: | Frontiers in Integrative Neuroscience |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fnint.2013.00039/full |
| _version_ | 1818303192981569536 |
|---|---|
| author | Elizabeth B Torres Rodrigo eQuian Quiroga He eCui Christopher eBuneo |
| author_facet | Elizabeth B Torres Rodrigo eQuian Quiroga He eCui Christopher eBuneo |
| author_sort | Elizabeth B Torres |
| collection | DOAJ |
| description | The posterior parietal cortex (PPC) is thought to play an important role in the planning of visually-guided reaching movements. However, the relative roles of the various subdivisions of the PPC in this function are still poorly understood. For example, studies of dorsal area 5 point to a representation of reaches in both extrinsic (endpoint) and intrinsic (joint or muscle) coordinates, as evidenced by partial changes in preferred directions and positional discharge with changes in arm posture. In contrast, recent findings suggest that the adjacent medial intraparietal area (MIP) is involved in more abstract representations, e.g. in converting target and hand position signals in visual coordinates into desired ‘displacement vectors’. Such a representation is suitable for planning reach trajectories involving straight paths to targets. However, it is currently unclear how MIP contributes to the planning of reaches requiring highly curved trajectories and moreover, whether these trajectories are represented purely in extrinsic coordinates or in intrinsic ones as well. Here we investigated the role of the PPC in these processes during an obstacle avoidance task that required the planning of curved trajectories that recruited different postural paths for which the animals had not been explicitly trained. We found that PPC planning activity was predictive of both the spatial and temporal aspects of upcoming trajectories. Moreover, activity of the same PPC neurons predicted the upcoming trajectory in both endpoint and joint coordinates. The predictive power of these neurons remained stable and accurate despite concomitant learning related changes in planning activity across task conditions. These findings suggest the role of the PPC can be extended from specifying abstract movement plans to expressing these plans as corresponding trajectories in both endpoint and joint coordinates. The PPC appears to contribute to reach planning at multiple levels of representation. |
| first_indexed | 2024-12-13T05:50:54Z |
| format | Article |
| id | doaj.art-caacb63d289045c7ae0a5d15ca32249e |
| institution | Directory Open Access Journal |
| issn | 1662-5145 |
| language | English |
| last_indexed | 2024-12-13T05:50:54Z |
| publishDate | 2013-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Integrative Neuroscience |
| spelling | doaj.art-caacb63d289045c7ae0a5d15ca32249e2022-12-21T23:57:33ZengFrontiers Media S.A.Frontiers in Integrative Neuroscience1662-51452013-05-01710.3389/fnint.2013.0003945463Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal CortexElizabeth B Torres0Rodrigo eQuian Quiroga1He eCui2Christopher eBuneo3Rutgers UniversityUniversity of LeicesterGeorgia Regents UniversityArizona State UniversityThe posterior parietal cortex (PPC) is thought to play an important role in the planning of visually-guided reaching movements. However, the relative roles of the various subdivisions of the PPC in this function are still poorly understood. For example, studies of dorsal area 5 point to a representation of reaches in both extrinsic (endpoint) and intrinsic (joint or muscle) coordinates, as evidenced by partial changes in preferred directions and positional discharge with changes in arm posture. In contrast, recent findings suggest that the adjacent medial intraparietal area (MIP) is involved in more abstract representations, e.g. in converting target and hand position signals in visual coordinates into desired ‘displacement vectors’. Such a representation is suitable for planning reach trajectories involving straight paths to targets. However, it is currently unclear how MIP contributes to the planning of reaches requiring highly curved trajectories and moreover, whether these trajectories are represented purely in extrinsic coordinates or in intrinsic ones as well. Here we investigated the role of the PPC in these processes during an obstacle avoidance task that required the planning of curved trajectories that recruited different postural paths for which the animals had not been explicitly trained. We found that PPC planning activity was predictive of both the spatial and temporal aspects of upcoming trajectories. Moreover, activity of the same PPC neurons predicted the upcoming trajectory in both endpoint and joint coordinates. The predictive power of these neurons remained stable and accurate despite concomitant learning related changes in planning activity across task conditions. These findings suggest the role of the PPC can be extended from specifying abstract movement plans to expressing these plans as corresponding trajectories in both endpoint and joint coordinates. The PPC appears to contribute to reach planning at multiple levels of representation.http://journal.frontiersin.org/Journal/10.3389/fnint.2013.00039/fullreachingPosterior parietal cortexplanningPostural controlobstacle avoidance |
| spellingShingle | Elizabeth B Torres Rodrigo eQuian Quiroga He eCui Christopher eBuneo Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex Frontiers in Integrative Neuroscience reaching Posterior parietal cortex planning Postural control obstacle avoidance |
| title | Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex |
| title_full | Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex |
| title_fullStr | Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex |
| title_full_unstemmed | Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex |
| title_short | Neural Correlates of Learning and Trajectory Planning in the Posterior Parietal Cortex |
| title_sort | neural correlates of learning and trajectory planning in the posterior parietal cortex |
| topic | reaching Posterior parietal cortex planning Postural control obstacle avoidance |
| url | http://journal.frontiersin.org/Journal/10.3389/fnint.2013.00039/full |
| work_keys_str_mv | AT elizabethbtorres neuralcorrelatesoflearningandtrajectoryplanningintheposteriorparietalcortex AT rodrigoequianquiroga neuralcorrelatesoflearningandtrajectoryplanningintheposteriorparietalcortex AT heecui neuralcorrelatesoflearningandtrajectoryplanningintheposteriorparietalcortex AT christopherebuneo neuralcorrelatesoflearningandtrajectoryplanningintheposteriorparietalcortex |