General Discussion 215 



Bartlett: It is quite true that from the fifties upwards, the attempt to 

 introduce new conditions of performance, new types of stimulation is 

 Hkely to be met by a relatively long learning stage. But I think that is 

 about the only thing that we can say about that. Most of the work that 

 we have been doing involves repetitive activities which have been 

 completely learnt. 



J. Verzdr: In that connection, and relative to Dr. Welford's work, 

 we have been doing some maze experiments with rats. We have tried 

 to study two problems: learning at different ages in a multiple T maze, 

 and relearning or memory of it at different stages during life. We have 

 found slightly lower learning in extreme old age, but the most interesting 

 thing was that certain of the old animals, about 40 per cent of the groups, 

 were not able to learn at all when presented with the maze for the first 

 time in old age, whereas the other 60 per cent learnt it within the 

 normal range, although rather more slowly than the young rats. The 

 second point was that in memory tests with groups of rats which had 

 learnt the maze at different ages, again in extreme old age about 40 per 

 cent forgot the task which they had learnt in earlier life, and were quite 

 unable to remember it, whereas the other 60 per cent of that same 

 group remembered as well as the younger rats. I don't know how far 

 that correlates with the work of Dr. Welford. 



Bartlett: I didn't say anything about the learning side of all this, 

 because if one doesn't take special precautions what you discovered 

 about the rats is equally true about human beings. That is to say the 

 learning processes which are characteristic of middle and older age are 

 quite different from those which are characteristic of the relatively 

 young. If the older people are presented with the same conditions of 

 learning as the young, they either learn less quickly or perhaps fail to 

 learn at all. But so far the evidence is that this is more a question of the 

 conditions under which the tests are given than it is of any absolute 

 capacity to learn. It seems extremely likely that as far as human 

 beings are concerned, there is no particular reason why people shouldn't 

 go on learning things as long as they live, or at any rate up to extreme 

 old age, provided they are given conditions of learning which are 

 suitable for their particular range. 



I think, too, there is a great deal of agreement between the results 

 about relearning which you have indicated with the rats and similar 

 cases with human beings. The only thing about it is that it seems as if 

 you can get rid of all these differences if you adjust your learning 

 conditions to the age range that is conqerned. It is very difficult to do 

 that with rat experiments, I think, but a little easier to do it with 

 human experiments. The whole progranune of our unit was to be 

 concerned also with learning, and we have got a good deal of evidence 

 about the learning processes which are characteristic of age ranges, and 

 they certainly are different in human beings for different age ranges, 

 but I haven't time to say anything about that. 



Parkes: I suppose in the case of the animal experiments the stimulus 

 applied to learning is the same for young as for old, is it? Loss of food, 

 or falling into a tank of water, or whatever? 



