A hearable comprises at least one microphone coupled with a wearable structure and a sensor processing unit disposed within the wearable structure and coupled with the microphone. A portion of the wearable structure is configured to be disposed within a user's ear. The sensor processing unit acquires audio data from the at least one microphone and head motion data from at least one motion sensor of the sensor processing unit. The head motion data describes motions of the user's head and comprises cranium motion data and mandible motion data. The sensor processing unit separates the mandible motion data from the head motion data, synchronizes the mandible motion data and the audio data into a synchronized data stream； classifies an activity of the head during a portion of the synchronized data stream； and generates a health indicator for the user based on the activity and the synchronized data stream.
