ACTION OF OPIUM ON PSYCHOLOGICAL REACTION TIME 27 



the predominant picture as could be seen by the prolongation of 

 the reaction time readings and greater variations in the same 

 and also, in case of associations, by a greater number of mistakes. 



Although the two stages of morphin action above described 

 were not always marked, a careful analysis of all the experiments 

 indicated that they were present in almost all the cases. The 

 primary stage of quickening or stimulation, in our opinion, 

 probably corresponds to the stage of euphoria or well-being so 

 well known to the pharmacologist and which occurs after small 

 doses of opiates. It is this euphoria or sense of well-being 

 which probably is responsible in a great measure for the greater 

 accuracy in mathematical calculations, especially in subjects with 

 a nervous temperament; inasmuch as the narcotic action of the 

 drug is just sufficient to "take the edge out" of the subject's anxiety. 

 The primary stage of increased efficiency noted agrees well with 

 the results of some other tests of mental efficiency produced by 

 opium per os or by mouth described by Mtinsterberg (12). 



The ordinary therapeutic doses of morphin (8 to 15 mgm. 

 or | to J grain) are generally too large to make the primary stage 

 of quickened reaction in normal individuals very noticeable and 

 it is for this reason often overlooked. 



It may be remarked in this place that although the nauseat- 

 ing effect of morphin, so commonly met with, occurred in several 

 of the subjects, the nausea had apparently no effect on the read- 

 ings. Indeed, in the individual who was most markedly affected in 

 this way (Dr. Kiang) the reaction time, if anything, was quickened. 



EFFECT OF COMBINATIONS 



Three experiments were made with injections of narcotin 

 hydrochloride alone and have already been described. No defi- 

 nite change in the reaction time was produced by the drug. 



Three experiments were made with a combination of mor- 

 phin and narcotin in the ratio of one to two, by administering the 

 drug called narcophin, which is a mixture of morphin and narco- 

 tin meconates. In two of the experiments there was a definite 

 increase in narcosis and corresponding prolongation or depres- 

 sion of the reaction time noted as compared with morphin alone, 



