EMG-based speech detection and communication

Systems and methods are provided for performing operations comprising: detecting, by one or more electromyograph (EMG) electrodes of an EMG communication device, subthreshold muscle activation signals of one or more muscles associated with speech production, the subthreshold muscle activation signals being generated in response to inner speech of a user; applying a machine learning technique to the subthreshold muscle activation signals to estimate one or more speech features corresponding to the subthreshold muscle activation signals, the machine learning technique being trained to establish a relationship between a plurality of training subthreshold muscle activation signals and ground truth speech features; generating visual or audible output based on the one or more speech features; and causing the visual or audible output to be processed by a messaging application to engage a feature of the messaging application.