Learning to learn in young adult, mature adult, and aged rats.

摘要

Barnes, Nadel and Honig (1980) report that different rules govern maze navigation in aged and non-aged rats. In their experiment, aged rats were more likely than adult rats to use a "response" strategy, whereas adult rats relied on a "place" strategy. In the present experiment 2.5-month (young adult), 5-month (mature adult), and 19-month (aged) rats were required to make sequential choices in an eight-arm radial maze. Two conditions were used, one in which rats had to select adjacent maze arms for reinforcement (adjacent condition), and one in which they had to skip an arm for reinforcement (skip condition). The experiment was designed to allow for use of "place" or "response" strategies, and to minimize the effect of age-related differences in motivation. Evidence is presented for an effect of age and condition. The aged rats had significantly lower error rates than the young adult rats in the skip condition. The results also indicate the presence of transfer learning. The young adult rats demonstrated proportionate levels of positively (30%) and negatively (39%) transferred learning in the skip condition, and their overall degree of transfer in this condition was greater than the other groups'.