Presenter Information

Lauryn BarrettFollow

Major

Biology

Anticipated Graduation Year

2020

Access Type

Open Access

Abstract

Electric activation of nerve conductance has provided many positive clinical outputs, including restoring function in the upper extremities, lower extremities, and respiratory system. Deep brain stimulation (DBS) of neuronal tissue represents a rapidly expanding viable therapeutic strategy for treating brain disorders. Limitations of this technique include the low biocompatibility of the implanted electrodes and inconsistency in the stimulation efficiency, due to inflammatory/immune reactions and glial scarring around the electrodes.

An alternative method to generate electric current inside the neural tissue is via electromagnetic induction by magnetic coils. Recently, miniature-sized magnetic coils have been used to activate selected neuronal subpopulations. The miniature coil can be covered with of biocompatible material, which prevents the direct contact between the electrode and neural tissue, eliminating numerous problems that may arise at the brain-electrode interface. However, the cellular mechanisms of single neural activation by the miniature coil is largely unknown.

We address this question by investigating activation of large neurons in the buccal ganglion of Aplysia californica under miniature coil stimulation. Biophysical computation indicates that the miniature coil can induce intensive electric field inside the buccal ganglion, where soma located. We used a modified multi-compartment model of motor neuron to evaluate the effects of magnetic stimulation. When the coil induced electric field was applied to the modeled neuron, it initiated action potential by depolarizing the membrane. The threshold of the action potential was dependent on the magnitude of the field intensity. It also depends on the orientation of the coil in relation to the neuron, which determines the location of membrane depolarization. Electrophysiological recording from the soma or the axon confirmed the activation of the neuron by the miniature coil.

These results raise the possibility to further optimize the design of the miniature coil and the stimulation protocol, for more efficient neuronal activation with this novel technology. Miniature coil control of neural activity can be further developed into an effective alternative to existing stimulation devices.

Faculty Mentors & Instructors

Dr. Hui Ye, Associate Professor, Biology Department

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.

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Control neuron activity with miniature magnetic coil – theoretical and experimental study

Electric activation of nerve conductance has provided many positive clinical outputs, including restoring function in the upper extremities, lower extremities, and respiratory system. Deep brain stimulation (DBS) of neuronal tissue represents a rapidly expanding viable therapeutic strategy for treating brain disorders. Limitations of this technique include the low biocompatibility of the implanted electrodes and inconsistency in the stimulation efficiency, due to inflammatory/immune reactions and glial scarring around the electrodes.

An alternative method to generate electric current inside the neural tissue is via electromagnetic induction by magnetic coils. Recently, miniature-sized magnetic coils have been used to activate selected neuronal subpopulations. The miniature coil can be covered with of biocompatible material, which prevents the direct contact between the electrode and neural tissue, eliminating numerous problems that may arise at the brain-electrode interface. However, the cellular mechanisms of single neural activation by the miniature coil is largely unknown.

We address this question by investigating activation of large neurons in the buccal ganglion of Aplysia californica under miniature coil stimulation. Biophysical computation indicates that the miniature coil can induce intensive electric field inside the buccal ganglion, where soma located. We used a modified multi-compartment model of motor neuron to evaluate the effects of magnetic stimulation. When the coil induced electric field was applied to the modeled neuron, it initiated action potential by depolarizing the membrane. The threshold of the action potential was dependent on the magnitude of the field intensity. It also depends on the orientation of the coil in relation to the neuron, which determines the location of membrane depolarization. Electrophysiological recording from the soma or the axon confirmed the activation of the neuron by the miniature coil.

These results raise the possibility to further optimize the design of the miniature coil and the stimulation protocol, for more efficient neuronal activation with this novel technology. Miniature coil control of neural activity can be further developed into an effective alternative to existing stimulation devices.