We investigated how the nervous system processes ambiguous cues from the otolith organs by measuring roll tilt perception elicited by two motion paradigms. In one paradigm (Tilt), 8 subjects were sinusoidally tilted in roll with the axis of rotation near ear-level. Stimulus frequencies ranged from 0.005 to 0.7 Hz and the peak amplitude of tilt was 20 deg. During this paradigm, subjects experienced a sinusoidal variation of inter-aural gravitational force with a peak of 0.34 G. The second motion paradigm (Translation) was designed to yield the same sinusoidal variation in inter-aural force, but did not include a roll canal cue. This was achieved by sinusoidally translating the subjects along their inter-aural axis. For the 0.7 Hz Translation trial, the subjects were simply translated from side-to-side. A centrifuge was used for the 0.005 to 0.5 Hz Translation trials; the subjects were rotated in yaw at 250 deg/s for 5 minutes before initiating sinusoidal translations yielding an inter-aural otolith stimulus composed of both centrifugal and radial acceleration. Using a somatosensory task to measure roll tilt perception, we found substantial differences in tilt perception during the two motion paradigms. Since the primary difference between the two motion paradigms was the presence of roll canal cues during roll tilt trials, these perceptual differences suggest that canal cues influence tilt perception. Specifically, rotational cues provided by the semicircular canals help the central nervous system resolve ambiguous otolith cues during head tilt, yielding more accurate tilt perception.