248 



PSYCHOLOGICAL EFFECTS OF ALCOHOL. 



Let us represent in schematic form some of the possible conditions of 

 variations in the action of an indicator consequent to the ingestion of a 

 drug. 



Apparent reinforcements of a process might be 

 due to: 



A. Increased action at some point in the direct 



process. 



B. The decreased action of some inhibiting 



factor. 



Under the first condition, i. c., increased action 

 at some point in the direct process: 



1. The drug may stimulate the indicator 



directly. (Pilocarpin on the ciliary 

 muscle.) 



2. It may make the indicator more sus- 



ceptible to its normal stimuli. 

 (Eserin.) 



3. It may really depress the indicator, 



but the depression may at first 

 produce Frolich's 1 "scheinbare Er- 

 regbarkeitssteigerung" due to the 

 summation of delayed processes. 

 (Action of COa and fatigue products 

 on muscle, nerve, and nerve centers.) 



4. The drug may act on some of the cen- 



tral links of the neuro-muscular arc, 

 (1) to stimulate them directly, (2) to 

 make them more susceptible to 

 stimulation, or (3) to produce 

 "scheinbare Erregbarkeitssteige- 

 rung." (Caffeine on central nervous 

 system; strychnine on the cord; 

 CC>2 and fatigue products on cen- 

 tral nervous system.) 

 o. It may supply some condition of metab- 

 olism, i. e., the drug may be a food, 

 or, like adrenalin, may facilitate the 

 liberation of stored foods. 



6. It may facilitate the diffusion of food 



or oxj'gen, by increased osmotic 

 pressure, or by decreased resistance 

 of permeable membranes. 



7. It may facilitate the distribution of 



food or oxygen by increasing the 

 flow of blood. (Increased pulse- 

 rate.) 



B. Similarly the drug may depress inhibit^ 

 ing or controlling mechanism in some 

 of the ways described under depres- 

 sion and so facilitate the process 

 that serves as indicator. 



Apparent depression of a process might be 

 due to: 



A. Decreased action at some point in the direct 



process. 



B. The increased action of some inhibiting 



factor. 

 Under the first condition of direct depression : 



1. The drug may narcotize the indicator 



directly. (Like curare on motor- 

 nerve endings, or cocaine on pain- 

 receptors.) 



2. It may make the indicator more sus- 



ceptible to depressing condition. 

 (Increased fatigability after strych- 

 nine.) 



3. It may directly increase the conserva- 



tive processes in the indicator by 

 delaying metabolism. (The best 

 example is not a drug, but cold.) 



4. It may act on some remote point of 



the neuro-muscular arc (1) to nar- 

 cotize it directly, (2) to make it 

 more susceptible to inhibiting stim- 

 uli, or (3) to increase in it some con- 

 servative process. (Morphine on 

 central nervous system; unknown to 

 writers if any drug has this specific 

 action; extreme form in normal 

 sleep.) 



5. The drug may destroy or render una- 



vailable some normal food or oxygen 

 supply. (Nerve-tissue under chlor- 

 oform narcosis.) 



6. It may hinder the diffusion of food or 



oxygen, by decreasing osmotic pres- 

 sure.* 



7. It may decrease the distribution of 



food or oxygen by decreasing the 

 blood flow, or by affecting the 

 hemoglobin, as CO. 



B. Similarly it may stimulate the inhibit- 

 ing and controlling mechanism in 

 some of the ways described under 

 stimulation of the direct process. 



Even this analysis does not exhaust the possibilities of complication ; 

 but it serves to illustrate the difficulties of the task of interpreting the 

 meaning of any specific increase or decrease in the operation of an indica- 

 tor. What we know of the physiological oxidation and pharmacology of 

 alcohol makes it clear that some of these complications really exist in 



^rolich, Zeitschr. f. allg. Physiol., 1909, 9, p. 1. 



