560 W. T. JAMES 



progress. The contrast of positive and negative signals and 

 varied stimulation is conducive to disturbance. 



The logical conclusion of the training in these dogs is quite 

 different from that found in group A. The dogs of B overact 

 each time the signal is presented, that is, overact in the sense 

 that most of the response has no connection at all with food 

 getting. This overaction is the nature of the animal. Due 

 to the inability to inhibit actions, these dogs become annoyed 

 by the repeated presentation of the same signal, and especially 

 by the introduction of negatives. The animals end the training 

 with an understanding of the laboratory procedure, but are 

 slightly disturbed by its repetition. This disturbance is evident 

 by increased action to the signals and general restlessness. 



Intermediate Groups 



Groups A and B represent the extremes in behavior, with 

 the animals of each group standing out as separate and dis- 

 tinct behavioral types. Yet it is quite evident that in an 

 animal as complicated as the dog, many individuals will fall 

 between the two extremes, having, to a greater or lesser degree, 

 the same general characteristics as the polar groups. These 

 intermediate animals will be referred to as behavioral types 

 A-plus and B-minus. The behavioral type A-plus includes 

 those animals which, although of the lethargic type, do not 

 reach the extreme of those in group A, and conversely, be- 

 havioral type B-minus includes animals of the active group 

 not quite reaching the extremes of group B. Of the thirty-six 

 animals trained, thirteen fall into the A-plus group while five 

 are classified as B-minus. These two groups grade into each 

 other and it is difficult in many cases to indicate whether a 

 dog is nearer the A or the B group. The main point of 

 emphasis here, however, is that the behavioral differences lie 

 in the degree of excitability as expressed by the particular 

 adjustment. 



Lethargic type A-plus. Thirteen animals fall into this 

 group, including the following: four bassethound-German 



