A re-examination of the effect of monaural stimulation upon the perception of verticality

A classic effect of sensory-tonic theory--viz., apparent verticality shifts opposite the side of monaural sound--has been questioned in three more recent studies. In attempting to evaluate these "failures to replicate," the present paper (a) elaborates upon certain findings only briefly reported earlier and summarizes additional findings which are supportive, (b) examines in detail the "failures to replicate," and (c) offers a tentative reconceptualization of the problem (viz., that the original effect occurs under the original conditions but becomes attenuated under conditions thought to reduce degree of differentiation between self and object) and briefly reports two new studies bearing on this reconceptualization.