72 K. S. LASHLEY 



increased restlessness after frontal injury in higher animals. 

 The animals of each group are arranged in the same order in the 

 two parts of the table so that their records for activity and rest 

 may be compared. Usually a great amount of active running 



Us accompanied by a reduced amount of time spent in absolute 

 nactivity, but there are marked exceptions to this rule. 

 f~* There is a great amount of individual variation between the 

 members of each of the groups and there seems to be no con- 

 stant relation between the amount of activity of the animals 

 and the number of trials required by them for learning the 

 problem on which they were trained. Three animals which 

 showed little activity (numbers 1, 7, and 11) required many 

 trials for learning (141, 107, and 101 respectively), but one 

 very inactive animal (13) learned in only 41 trials. Two very 

 active animals (18 and 19) required few trials (51 and 27 respec- 

 tively), but an equally active animal (8) required 97 trials for 

 learning. There is no absolute correspondence between the 

 general activity and the rate of learning. 



The small number of animals studied and the great amount of 

 individual variation makes the significance of differences be- 

 _jLween the groups very questionable. The test seems to have 

 brought out the fact, however, that cerebral injury has no 

 constant effect upon general activity which could account for 

 any great differences in rate of learning found between normal 

 and partially decerebrate animals. 



A second question respecting the general activities of the 

 operated animals is of great importance in interpretation of the 

 results of training. Does destruction of parts of the cerebrum 

 so disturb the instinctive behavior of the animals as to modify 

 the effects of the stimuli used as incentives to learning? I have 

 kept operated animals for periods up to five months after opera- 

 tion and have not been able to discover any change in their 

 instinctive reactions. Animals of every group showed sexual 

 activities, exploration of new situations, great eagerness for 

 food after periods of starvation, efforts to be the bottom one 

 of the pile when several animals slept together in one cage, 

 etc. Except for motor incoordination which appeared in a few 



