Design strategies for dynamic closed-loop optogenetic neurocontrol in vivo.

Area of Science:

• Neuroscience
• Biotechnology
• Systems Biology

Background:

• Optogenetic stimulation is a powerful tool for modulating neural activity and understanding neural circuits.
• Current methods often use open-loop or basic closed-loop stimulation, limiting precise, real-time control.
• Disentangling complex neural circuits requires precise manipulation of neuronal activity.

Purpose of the Study:

• To develop and demonstrate a design approach for precise optogenetic control of neuronal firing rate modulation using continuous feedback.
• To enable real-time adjustment of optogenetic stimulation based on neural activity.
• To improve the ability to functionally dissect neural circuits.

Main Methods:

• Utilized the rodent somatosensory thalamus as an experimental model.
• Employed a moving average exponential filter for online estimation of firing rate from extracellular single-unit spiking.
• Implemented a proportional-integral (PI) controller using the estimated firing rate as feedback, designed based on a linear-nonlinear Poisson (LNP) model.

Main Results:

• Achieved robust closed-loop control of neuronal firing rates using the developed feedback system.
• Demonstrated good tracking of both sinusoidal and non-sinusoidal firing rate targets.
• Showcased effective rejection of unmeasured disturbances and manipulation of trial-to-trial variability.

Conclusions:

• Continuous feedback-guided optogenetic stimulation offers precise control over neuronal firing rates.
• This approach is crucial for disambiguating neural circuit functions in the face of changing activity.
• Real-time adjusted stimulation improves data quality for optogenetic manipulation studies.