This study was concerned with an evaluation of the visual cues used by a driver at night as he decides he is overtaking the vehicle in front of him. Three cues were selected for study: 1. change in size of taillight surfaces. 2. change in apparent brightness of taillight surfaces. 3. changes in visual angle subtended by taillights. Two of these variables were manipulated, the third was the one on which an "overtaking" decision had to be based. The results of this test were compared with a control condition in which the taillights appeared as normal. One of the results shows that size was not significant.
Abstract