Hockenbury Discovering Psychology 5th txtbk

214 CHAPTER 5 Learningcognitive mapTolman’s term for the mental representationof the layout of a familiar environment.latent learningTolman’s term for learning that occurs inthe absence of reinforcement but is notbehaviorally demonstrated until a reinforcerbecomes available.of responses required to get to the food. Tolman believed instead that the rats eventuallybuilt up, through experience, a cognitive map of the maze—a mental representationof its layout.As an analogy, think of the route you typically take to get to your psychology classroom.If a hallway along the way were blocked off for repairs, you would use yourcognitive map of the building to come up with an alternative route to class. Tolmanshowed experimentally that rats, like people, seem to form cognitive maps (Tolman,1948). And, like us, rats can use their cognitive maps to come up with an alternativeroute to a goal when the customary route is blocked (Tolman & Honzik, 1930a).Tolman challenged the prevailing behaviorist model on another important point.According to Thorndike, for example, learning would not occur unless the behaviorwas “strengthened,” or “stamped in,” by a rewarding consequence. But Tolmanshowed that this was not necessarily the case. In a classic experiment, three groupsof rats were put in the same maze once a day for several days (Tolman & Honzik,1930b). For group 1, a food reward awaited the rats at the end of the maze. Theirperformance in the maze steadily improved; the number of errors and the time ittook the rats to reach the goal box showed a steady decline with each trial. The ratsin group 2 were placed in the maze each day with no food reward. They consistentlymade many errors, and their performance showed only slight improvement. Theperformance of the rats in groups 1 and 2 was exactly what the traditional behavioristmodel would have predicted.Now consider the behavior of the rats in group 3. These rats were placed in themaze with no food reward for the first 10 days of the experiment. Like the rats ingroup 2, they made many errors as they wandered about the maze. But, beginningon day 11, they received a food reward at the end of the maze. As you can see inFigure 5.7, there was a dramatic improvement in group 3’s performance from day 11to day 12. Once the rats had discovered that food awaited them at the end of themaze, they made a beeline for the goal. On day 12, the rats in group 3 ran the mazewith very few errors, improving their performance to the level of the rats in group 1that had been rewarded on every trial!Tolman concluded that reward—or reinforcement—is not necessary for learningto take place (Tolman & Honzik, 1930b). The rats in group 3 had learned the layoutof the maze and formed a cognitive map of the maze simply by exploring it for10 days. However, they had not been motivated to demonstrate that learning untila reward was introduced. Rewards, then, seem to affect the performance of what has32Figure 5.7 Latent Learning Beginningwith day 1, the rats in group 1 received afood reward at the end of the maze, andthe number of errors they made steadilydecreased each day. The rats in group 2never received a food reward; they mademany errors as they wandered about inthe maze. The rats in group 3 did notreceive a food reward on days 1 through10. Beginning on day 11, they received afood reward at the end of the maze. Noticethe sharp decrease in errors on day12 and thereafter. According to Tolman,the rats in group 3 had formed a cognitivemap of the maze during the first 11 daysof the experiment. Learning had takenplace, but this learning was not demonstrateduntil reinforcement was present—aphenomenon that Tolman called latentlearning.Source: Tolman & Honzik (1930b).Average errors in maze30282624222018161412108642Group 1Received food rewardevery day.1 2 3Food reward introducedfor group 3.Group 2Never received foodreward.4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22Days of training in mazeGroup 3No food reward untilthe 11th day.