Getting the measure of vergence weight in nearness perception

Combining multiple sources of information allows the human nervous system t o construct an approximately Euclidean representation of near (personal) sp ace. Within this space, binocular vergence is an important source of egocen tric distance information. We investigated how the nervous system determine s the significance (weight) accorded to vergence information when other (re tinal) distance cues are present. We found that weight decreases with (1) i ncreasing discrepancy between vergence information and other cues and (2) r educed vergence demand. The results also provided evidence that the nervous system represents vergence related distance information in units of nearne ss (the reciprocal of distance).