'9-° 



HANDBl H iK « II 1'IIYsHlI (>(,Y 



M 1 ROPHYSIOLOGY III 



Models 



Bench Marks of Neurophysiology 

 Axon properties 

 Neuron properties 

 Neuron groups 

 An Information Model 

 An Action Wave Model 

 Formulation 



U .ims in a neuron mass 

 Controls 



Reactivation properties 

 Epitome 



Experimental support 

 ( llose 



. . . there is something wonderful in the idea that man's 

 brain is the greatest machine of all, imitating within its tins 

 network events happening in the most distant stars, predicting 

 their appearances with accuracy, and finding in this power of 

 successful prediction and communication the ultimate feature 

 of consciousness. ... I see no reason to suppose that the 

 processes of reasoning ntf fundamentally different from the 

 mechanism of physical nature. On our model theory neural or 

 other mechanisms can imitate or parallel the behaviour and 

 interaction of physical objects and so supply us with informa- 

 tion on physical processes which are not directly observable to 

 us ( )ur thought, then, has objective validity because it is not 

 fundamentally different from objective reality but is specially 

 suited fbl imitating it — that is our suggested answer. It sets no 

 crabbed limit to the attempt of thought to understand and 

 express the universe. 



Craik, K. J. W. The Nature of 

 Explanation, p. 99 (49). 



The picture of skilled performance built up by modern 

 ire lies is one ul a complex interaction between man and 

 environment. Continuously the skilled man must select the 

 correct cues from the environment, take decisions upon them 

 which may possibly involve prediction of the future, and 

 initiate sequences of responses whose progress is controlled bj 

 feed-back, either through the original decision-making mech- 

 anism, or through lower-order loops. The processes of 

 filtering the information from the senses, of passing it through 

 a limited capacity channel, ami of storing it temporarily are 

 onl) pan ol the total skilled performance. Hut they are of the 



general nature as the other processes involved, and 



1 1. 11 in/.- with tin broad view "I skill which is now developing. 



BrOADBI NT, D I I' 



Communication, p. 295 



IS iRODl 1 I li i\' 



Slate (if ih' S( ietu 1 



living is seeking. Living things ride .1 double rail 

 through time. I In- organism (oi org or system) .11 



I his ' haptei is partly a review of reviews the mam fine 

 chapters in tins Handbook but is more a personal essa) I 



any instant possesses, ;i- a product of its individual 

 history, a more or less unique heterogeneity which 

 reacts to its present and its expected environment. 

 Early in evolution the presenting physical surround 

 was salient. Later, emphasis shifted to the biological 

 and, especially in man, to the future and the social 

 aspects of the environment. The outcome of actions 

 as good or had, adaptive or nonadaptivc, is judged 

 in terms of development of the individual or evolution 

 of the species projected against the future environ- 

 ment. There is always some type of goal or "desired" 

 direction at any time; but since this is as true for a 

 drop of water 'seeking' the sea or a population evolv- 

 ing adaptive structures as it is for a seedling 'seeking' 

 the light or a rat learning a maze, volition and freedom 

 are not at issue. 



So living is riding; the rails of the expected and the 

 desired, a double projection from the existing, an 

 unending tracking performance based on a probability 

 calculus [see Yickers (284)]. Whether a man actually 

 sets his goals more than does an ameba is still debated, 

 but he surely exhibits more conscious foresight in 

 pursuing them. A civilized man in his psychosocial 

 community faces wide divergence of the expected 

 from the hoped-for or feared, with the intricate 

 overtones of behavior involved in enculturation and 

 self-restraint, the psychiatrist's superego. This lull 



have read, with great profit, all available manuscripts (several 

 were not), have made voluminous notes and have drawn freely 

 on these materials in my own contribution. (Much of this 

 initial digestion was accomplished while I was guest praelector 

 of the University of St. Andrews, Scotland — for which oppor- 

 tunitv I am grateful.) Handbook chapters have been used 

 liberally as references for general or particular statements. 

 I hey are consistently referred to in the text by the authors' 

 names without reference numbers 1 On the other hand, it 

 would have been oppressive to cite ea< h chapter on each point 

 to which it related, so the references are somewhat impression- 

 istic, depending on which was in mind as I wrote. 1 he same 

 selection, based on undisciplined recall, has influenced the use 

 ul other citations Work that tern. lined long in mv mind or 

 was recently encountered in far from systematic reading <•> 

 Conferring has been mentioned That my own writings have 

 received undue emphasis will thus lie understood anil. I hopl 

 forgiven In this, Dl Gerard has had 0111 full encouragement 

 Editors Needless to say, tie- bulk ill classical work in neuro- 

 physiology is cited in other Hal I I' ipters and dues not 

 receive further note here; many great names do not appear in 

 the list of references rhis < hapter, rathet than being a hopeless 

 attempt at restating the findings ol a generation or two "i 

 investigators of the nervous svstem. is the residue '\.<i> 1 s.iv . 



.111.1111 nl mv own exposure to the work and thought ol 



man) 1 olli agui s and ol s ime teachers and intimate friends in 

 this goodl) band ol explorers I thank man) who have con- 

 tributed in it line, tlv 1.1 indirectly, It. in turn, may help 

 contribute a flavor to the intellectual food in the Handi 



