NERVOUS INTEGRATIONS IN MAN 259 



to the gullet, and so to the stomach, this despite its com- 

 plexity, can go forward after removal of all of the higher 

 parts of the brain and the whole of that portion which 

 we have termed mental. 



The Hypothalamus. If the brain stem is transected so as 

 to leave intact a few millimeters of the base of the brain, 

 known as the hypothalamus, the preparation being other- 

 wise the same as that used for study of the decerebrate 

 condition, one observes a most striking series of phenomena. 

 The animal is restless and exhibits periodic outbursts which 

 have been appropriately termed "sham rage." The pupils 

 become dilated, eyes protruded, fur erect and the animal 

 may snarl, growl and show his teeth, and exhibit in addition 

 periodic running movements. Occasionally, if gently patted 

 the animal may purr and wag its tail inordinately and show 

 other evidence of intense pleasure. In the small area of the 

 hypothalamus there he the centers for emotional expression, 

 and when these are released from higher control the thresh- 

 old for ehcitation of emotional responses is lowered. 



In man one sees the direct counterpart of such a state 

 under the influence of certain drugs, notably ether, alcohol 

 and "laughing" gas, when vigorous expressions of rage or of 

 exceptional delight may alternate with surprising rapidity. 

 Symptoms of acute mania associated with outbursts of 

 activity • of the sympathetic nervous system akin to the 

 sham rage or to the expression of pleasure seen in hypothal- 

 amic animals have been observed in man after injuries 

 to the base of the brain. From this and other evidence the 

 hypothalamus has come to be looked upon as the chief 

 ganglion of the sympathetic system, and the region of the 

 brain chiefly concerned with emotional expression.^ 



HIGHEST NERVOUS CENTERS 



The supreme outcome of nervous integration is mind, 

 and in man mind dominates the organism. Could we look 

 quite naively at the body as indwelt by mind we might 

 perhaps suppose mind diff'used throughout it, not locahzed 

 in any one particular portion at all. That it is locahzed and 



1 The relation of the hypothalamus to emotional expression has lately been 

 (fealt with at length by W. B. Cannon (1927) and by his pupil P. Bard (1928). 



