T26 HUMAN BIOLOGY 



REPRESENTATIONAL OR IMAGINAL PROCESSES 



For ages mankind has assumed and believed that ideation, 

 thought, and reasoning are distinctively and probably 

 exclusively human. But recently the development of new 

 techniques and the accumulation of observational data, 

 through the comparative study of psychobiological phenom- 

 ena in the primates, have essentially altered the status of 

 knowledge. It is now legitimate to state that ideas, simple 

 thought processes, and primitive forms of reasoning exist 

 in the anthropoid apes, or that functional equivalents cause 

 the animals to act as though experiencing ideas and directed 

 by thoughts. One may take one's choice as between the 

 natural inference that similarity in adaptive behavior 

 implies similarity in the essentials of experience or that 

 rationality may be simulated by some mechanism which is 

 possessed by apes but not by men. 



Within the compass of a few paragraphs typical observa- 

 tions or evidences of representational processes, or their 

 functional equivalents, in the infrahuman primates may be 

 indicated but not adequately described. In accordance with 

 analysis of human experience these processes are of two 

 principal types: the reproductive and the creative. The 

 former are usually called memory processes; the latter, 

 processes of constructive or creative imagination. Either 

 type of process may involve imagery, and if the subject of 

 observation is capable of experiencing images they are 

 almost certain to appear in any representational process. 



Whereas in mammals other than the primates, notably in 

 rats, guinea pigs and rabbits, a problematic environmental 

 situation cannot ordinarily be responded to appropriately 

 for more than a few seconds, and at best a very few minutes, 

 after it has disappeared from view; monkeys, apes and men 

 apparently are able to respond adaptively and as if with 

 definite memory of the situation after much longer intervals 

 of delay. Typical experiments will render this important 

 psychological contrast clearer. 



The subject sits before three doorways, through one of 

 which when released it may pass to get its dinner. Everything 

 in readiness, the experimenter exhibits for a moment the 



