FACE ENGAGED OR NOT FREE. 207 



The facial muscles are indices of the brain action 

 for the same reason that postures or movements of 

 the hands are expressive. It is only when the 

 facial muscles are free and disengaged that they 

 can receive, and be acted upon by, the finer nerve- 

 currents coming to them from the brain. It is, then, 

 the disengaged face in which we see the most 

 expression of that action of the brain which pro- 

 duces the emotions and mentation. 



Observing a man while his facial muscles are 

 performing the movements necessary to eating, or 

 while a strong light is shining in his eyes, does not 

 afford a good opportunity for observing the effect of 

 mental action in producing mobile conditions of 

 expression. While the facial muscles are passive, 

 and not under the influence of any strong stimulus, 

 they are much more impressionable to nerve- 

 currents coming down from the centres of mentation. 

 When strongly acted on by some reflex stimulus, 

 they are less impressionable to the slight ever- 

 changing currents coming from the centres of 

 mentation. 



When the orbicularis muscles are contracted from 

 a light shining in the eyes, when the semi-reflex 

 actions of eating are going on, or while whistling, 

 the facial muscles are less expressive of the condi- 

 tion of the mind. Conditions of disease of the 

 brain may render the movements of the face inex- 

 pressive of the state of the brain as regards its 

 function of mentation. 



The following case should probably be classed as 

 one of athetosis of the face, associated with petit mal. 



