Effect of Sleep on Memory This article is from The Journal of Experimental Psychology, and was written on an experiment performed by psychologist Bruce R. Ekstrand, from the University of Colorado. He experimented on the effects that sleep has on one’s memory, after learning a particular bit of knowledge, in this case a certain list of twelve three-letter words. There were several different ways Ekstrand went about discovering whether sleep would facilitate memory or not. Out of the entire group of people who he experimented on, some of them were given nothing but a simple list to memorize, some were given a pro-active interfering list, and some were given a retroactive interfering list. For his core measurement method, he used a 3x2 factorial chart. In this factorial were the three types of interference learning he used- retroactive, pro-active, and no interference. The factorial’s two-part were the levels of sleep that those who were experimented on got – either eight hours of sleep, or none. The participants would have to learn these certain lists and associations with the lists, and perhaps pro-active or retroactive learning if they were assigned to that particular group. Half of the participants, chosen at random, would then sleep in the laboratory for approximately eight hours before being awakened in the morning, being urged to fall asleep as soon as they could, and with the average time it takes on to fall asleep being taken into account. Those who had to stay awake would leave for eight hours and return. Both groups would assure that no rehearsing had been done, and they would then have to recall the lists and associations. In most of the rehearsals for testing, sleep proved to facilitate recall better than staying awake did. However, the facilitation was not incredibly significant. In some of the pro-active and retroactive cases, sleep did not actually facilitate memory...
