AN EXPERIMENTALLY INDUCED CONFLICT BETWEEN VISION AND PROPRIOCEPTION

Settings of a bar so that if felt horizontal were examined under conditions where subjects were given false visual information of the slant of the bar. With a distortion of 15° subjects reported that the bar felt horizontal when it in fact looked horizontal. Although for larger distortions most subjects became aware of a conflict between what was seen and felt, few were able to make accurate settings. The bar tended to be set at a slant between the visual horizontal and the physical horizontal. Settings were variable over trials but there was no trend towards greater accuracy. The data indicate that in making spatial judgements more reliance is placed on visual than proprioceptive input.