"Time is this rubbery thing,” Eagleman said. “It stretches out when you really turn your brain resources on, and when you say, ‘Oh, I got this, everything is as expected,’ it shrinks up.” The best example of this is the so-called oddball effect—an optical illusion that Eagleman had shown me in his lab. It consisted of a series of simple images flashing on a computer screen. Most of the time, the same picture was repeated again and again: a plain brown shoe. But every so often a flower would appear instead. To my mind, the change was a matter of timing as well as of content: the flower would stay onscreen much longer than the shoe. But Eagleman insisted that all the pictures appeared for the same length of time. The only difference was the degree of attention that I paid to them. The shoe, by its third or fourth appearance, barely made an impression. The flower, more rare, lingered and blossomed, like those childhood summers."