Adversarial Domain Adaptation for Stable Brain-Machine Interfaces

Ali Farshchian, Juan A. Gallego, Joseph P. Cohen, Yoshua Bengio, Lee E. Miller, Sara A. Solla

Abstract:

Brain-Machine Interfaces (BMIs) have recently emerged as a clinically viable option
to restore voluntary movements after paralysis. These devices are based on the
ability to extract information about movement intent from neural signals recorded
using multi-electrode arrays chronically implanted in the motor cortices of the
brain. However, the inherent loss and turnover of recorded neurons requires repeated
recalibrations of the interface, which can potentially alter the day-to-day
user experience. The resulting need for continued user adaptation interferes with
the natural, subconscious use of the BMI. Here, we introduce a new computational
approach that decodes movement intent from a low-dimensional latent representation
of the neural data. We implement various domain adaptation methods
to stabilize the interface over significantly long times. This includes Canonical
Correlation Analysis used to align the latent variables across days; this method
requires prior point-to-point correspondence of the time series across domains.
Alternatively, we match the empirical probability distributions of the latent variables
across days through the minimization of their Kullback-Leibler divergence.
These two methods provide a significant and comparable improvement in the performance
of the interface. However, implementation of an Adversarial Domain
Adaptation Network trained to match the empirical probability distribution of the
residuals of the reconstructed neural signals outperforms the two methods based
on latent variables, while requiring remarkably few data points to solve the domain
adaptation problem.

Keywords: Brain-Machine Interfaces, Domain Adaptation, Adversarial Networks

TL;DR: We implement an adversarial domain adaptation network to stabilize a fixed Brain-Machine Interface against gradual changes in the recorded neural signals.