Abstract
Visual direction in the context of cyclopean vision continues to be a topic of debate. The established view is that we perceive the world as if from a single vantage point — the cyclopean eye — located midway between the two eyes. A set of rules, known as the laws of visual direction, summarize these ideas and allow one to predict visual direction of most objects in the field of view. Erkelens and van Ee (2002) have claimed that the concept of a cyclopean eye is irrelevant, especially for predicting visual direction of monocular stimuli during a purely visual task. Additionally, they criticized the methodology of previous experiments in this area. We challenge their claim and provide support for the relevance of the cyclopean eye concept and its usefulness in predicting absolute visual direction of monocular stimuli. At the same time we improve on some possible shortcomings of past studies. Using an arrangement of polaroid filters we presented light emitting diodes to the observers monocularly, without them knowing which eye was being stimulated. Viewing distance was 9–11 cm (depending on the observer's interocular distance), while fixation distance was 30 cm. Observers judged the absolute and relative visual directions of the LEDs located in front of various parts of their faces. This was a visual task since no motor response was required. Our results conform to the predictions made using the laws of visual direction and are in agreement with the concept of cyclopean vision. Reference: Erkelens, C. J., & van Ee, R., (2002). The role of the cyclopean eye in vision: sometimes inappropriate, always irrelevant. Vision Research, 42, 1157–1163.