Skip to Main content Skip to Navigation
Journal articles

Mapping Horizontal Spread of Activity in Monkey Motor Cortex Using Single Pulse Microstimulation

Abstract : Anatomical studies have demonstrated that distant cortical points are interconnected through long range axon collaterals of pyramidal cells. However, the functional properties of these intrinsic synaptic connections, especially their relationship with the cortical representations of body movements, have not been systematically investigated. To address this issue, we used multielectrode arrays chronically implanted in the motor cortex of two rhesus monkeys to analyze the effects of single-pulse intracortical microstimulation (sICMS) applied at one electrode on the neuronal activities recorded at all other electrodes. The temporal and spatial distribution of the evoked responses of single and multiunit activities was quantified to determine the properties of horizontal propagation. The typical responses were characterized by a brief excitatory peak followed by inhibition of longer duration. Significant excitatory responses to sICMS could be evoked up to 4 mm away from the stimulation site, but the strength of the response decreased exponentially and its latency increased linearly with the distance. We then quantified the direction and strength of the propagation in relation to the somatotopic organization of the motor cortex. We observed that following sICMS the propagation of neural activity is mainly directed rostro-caudally near the central sulcus but follows medio-lateral direction at the most anterior electrodes. The fact that these interactions are not entirely symmetrical may characterize a critical functional property of the motor cortex for the control of upper limb movements. Overall, these results support the assumption that the motor cortex is not functionally homogeneous but forms a complex network of interacting subregions.
Document type :
Journal articles
Complete list of metadatas

Cited literature [46 references]  Display  Hide  Download

https://hal-amu.archives-ouvertes.fr/hal-01464318
Contributor : Alexa Riehle <>
Submitted on : Friday, February 10, 2017 - 10:58:48 AM
Last modification on : Friday, January 10, 2020 - 3:10:18 PM
Long-term archiving on: : Thursday, May 11, 2017 - 12:33:03 PM

File

HaoRiehleBrochier2016.pdf
Publisher files allowed on an open archive

Identifiers

Collections

Citation

Yaoyao Hao, Alexa Riehle, Thomas Brochier. Mapping Horizontal Spread of Activity in Monkey Motor Cortex Using Single Pulse Microstimulation. Frontiers in Neural Circuits, Frontiers, 2016, 10, pp.104. ⟨10.3389/fncir.2016.00104⟩. ⟨hal-01464318⟩

Share

Metrics

Record views

266

Files downloads

284