A Chronically Implantable Bidirectional Neural Interface for Non-human Primates

Area of Science:

• Neuroscience
• Biomedical Engineering
• Optogenetics

Background:

• Optogenetics offers potential for epilepsy, neuroprosthetics, and neural circuit studies.
• Clinical translation requires chronic stimulation/monitoring devices with minimal brain trauma.

Purpose of the Study:

• To develop a chronically implantable device for brain photostimulation in non-human primates.
• To enable simultaneous photostimulation and electrocorticography (ECoG) recording.

Main Methods:

• Utilized a micro-light-emitting diode (LED) array on a flexible polyimide film.
• Combined the micro-LED array with a whole-cortex ECoG electrode array.
• Epidurally implanted the device in common marmosets after viral transduction of Channelrhodopsin-2 (ChR2) in the cerebral cortex.

Main Results:

• Successfully recorded neural activity during photostimulation in awake monkeys for 4 months.
• Observed a gradual increase in neural responses for ~8 weeks post-injection, stabilizing for the next 8 weeks.
• Demonstrated semi-invasive, simultaneous stimulation and recording capabilities with long-term implantation.

Conclusions:

• The developed micro-LED and ECoG device allows for chronic, semi-invasive optogenetic stimulation and neural recording in non-human primates.
• This represents significant progress towards clinical applications of optogenetics.
• The device facilitates long-term studies of neural circuit dynamics and therapeutic interventions.