Disclosed herein are apparatus and methods for delivering bone conduction stimuli for measuring the gravitation receptor functions of the inner ear. In some embodiments, an apparatus may include (i) an impactor operatively linked to a guide disposed within a housing and (ii) an electrically driven actuator enclosed within the housing. The electrically driven actuator may be configured to cause the impactor to (i) travel to a striking point to deliver a mechanical bone conduction stimulus for transmission to a skull bone and (ii) controllably decelerate prior to the instance of stimuli delivery.