The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans.
Substantial evidence has highlighted the significant role of associative brain areas, such as the posterior parietal cortex (PPC) in transforming multimodal sensory information into motor plans. However, little is known about how different sensory information, which can have different delays or be a...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2015-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4529220?pdf=render |
| _version_ | 1818188808959557632 |
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| author | Derrik E Asher Nicolas Oros Jeffrey L Krichmar |
| author_facet | Derrik E Asher Nicolas Oros Jeffrey L Krichmar |
| author_sort | Derrik E Asher |
| collection | DOAJ |
| description | Substantial evidence has highlighted the significant role of associative brain areas, such as the posterior parietal cortex (PPC) in transforming multimodal sensory information into motor plans. However, little is known about how different sensory information, which can have different delays or be absent, combines to produce a motor plan, such as executing a reaching movement. To address these issues, we constructed four biologically plausible network architectures to simulate PPC: 1) feedforward from sensory input to the PPC to a motor output area, 2) feedforward with the addition of an efference copy from the motor area, 3) feedforward with the addition of lateral or recurrent connectivity across PPC neurons, and 4) feedforward plus efference copy, and lateral connections. Using an evolutionary strategy, the connectivity of these network architectures was evolved to execute visually guided movements, where the target stimulus provided visual input for the entirety of each trial. The models were then tested on a memory guided motor task, where the visual target disappeared after a short duration. Sensory input to the neural networks had sensory delays consistent with results from monkey studies. We found that lateral connections within the PPC resulted in smoother movements and were necessary for accurate movements in the absence of visual input. The addition of lateral connections resulted in velocity profiles consistent with those observed in human and non-human primate visually guided studies of reaching, and allowed for smooth, rapid, and accurate movements under all conditions. In contrast, Feedforward or Feedback architectures were insufficient to overcome these challenges. Our results suggest that intrinsic lateral connections are critical for executing accurate, smooth motor plans. |
| first_indexed | 2024-12-11T23:32:49Z |
| format | Article |
| id | doaj.art-1a8520831a54424b941fefe8cef2f9df |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-11T23:32:49Z |
| publishDate | 2015-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-1a8520831a54424b941fefe8cef2f9df2022-12-22T00:45:58ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01108e013466910.1371/journal.pone.0134669The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans.Derrik E AsherNicolas OrosJeffrey L KrichmarSubstantial evidence has highlighted the significant role of associative brain areas, such as the posterior parietal cortex (PPC) in transforming multimodal sensory information into motor plans. However, little is known about how different sensory information, which can have different delays or be absent, combines to produce a motor plan, such as executing a reaching movement. To address these issues, we constructed four biologically plausible network architectures to simulate PPC: 1) feedforward from sensory input to the PPC to a motor output area, 2) feedforward with the addition of an efference copy from the motor area, 3) feedforward with the addition of lateral or recurrent connectivity across PPC neurons, and 4) feedforward plus efference copy, and lateral connections. Using an evolutionary strategy, the connectivity of these network architectures was evolved to execute visually guided movements, where the target stimulus provided visual input for the entirety of each trial. The models were then tested on a memory guided motor task, where the visual target disappeared after a short duration. Sensory input to the neural networks had sensory delays consistent with results from monkey studies. We found that lateral connections within the PPC resulted in smoother movements and were necessary for accurate movements in the absence of visual input. The addition of lateral connections resulted in velocity profiles consistent with those observed in human and non-human primate visually guided studies of reaching, and allowed for smooth, rapid, and accurate movements under all conditions. In contrast, Feedforward or Feedback architectures were insufficient to overcome these challenges. Our results suggest that intrinsic lateral connections are critical for executing accurate, smooth motor plans.http://europepmc.org/articles/PMC4529220?pdf=render |
| spellingShingle | Derrik E Asher Nicolas Oros Jeffrey L Krichmar The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. PLoS ONE |
| title | The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. |
| title_full | The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. |
| title_fullStr | The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. |
| title_full_unstemmed | The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. |
| title_short | The Importance of Lateral Connections in the Parietal Cortex for Generating Motor Plans. |
| title_sort | importance of lateral connections in the parietal cortex for generating motor plans |
| url | http://europepmc.org/articles/PMC4529220?pdf=render |
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