FIGURE 3.4 Demonstration of the Blind Spot Hold this book a few feet in front of you. Close your right eye and stare at the insect spray can with your left eye. Slowly bring the book toward your face. At some point the spider will disappear because you have focused it onto the part of your retina where the blind spot is located. Notice, however, that you still perceive the spider web. That’s because your brain has filled in information from the surrounding area (Komatsu, 2006).