TAPPING THE HEAD ACTIVATES THE VESTIBULAR SYSTEM - A NEW USE FOR THE CLINICAL REFLEX HAMMER

We investigated the use of skull taps with a modified clinical reflex hammer as a method of vestibular activation. Using recently described EMG techniques to measure vestibulocollic reflexes in response to clic ks, we were able to show analogous short-latency potentials to taps. T he earliest responses were invariably absent on the side of a previous vestibular nerve section but were preserved in profound sensorineural or conductive hearing loss. We propose that the taps activated the ve stibular apparatus directly by a bone-conducted vibration wave.