286 MAN --AN ADAPTIVE MECHANISM 



are precisely the same as the cycle of changes produced 

 by the emotions, physical exertion or other forms 

 of kinetic stimulation. For example, according to the 

 dosage, strychnin causes intense excitement con- 

 vulsions ending in exhaustion and death ; a lesser 

 degree of excitation followed by lassitude ; slight 

 stimulation without notable after-results ; while tho 

 histologic changes in the brain, adrenals and liver - 

 especially marked in the brain display these physio- 

 logic alterations in proportional hyperchromaiism in 

 the active stages and %pochromatism in the stages of 

 reaction. 



Opium 



Abundant clinical and experimental evidence exists 

 to show that opium blocks or depresses the cerebral 

 link of the kinetic system. Every one knows that deep 

 opium narcotization prevents anger, fear, shock, mus- 

 cular and mental work, and in addition the clinician 

 knows that opium diminishes fever and controls 

 anaphylactic phenomena. Of most vital significance 

 to our theme, however, is the fact, established by 

 laboratory experimentation, that deep opium narcoti- 

 zation prevents the output of adrenin. (See Fig. 48.) 

 Even in large doses, however, opium does not prevent 

 the action of adrenin injected intravenously. We 

 have shown in previous chapters that adrenin is a 

 powerful activator of the kinetic system, but it may be 

 well in this instance to refer again to the fact that 

 adrenin causes all the phenomena of kinetic activity 

 -with one exception, an increase in adrenal out- 

 put. Adrenin causes all the phenomena of fever, 



