426 MENTAL FUNCTION 



that of dreams. Hallucinations are about half as frequent again in 

 women as in men, and more common in Brazilian women, for example, 

 than in English women. 



Delusions exist wherever knowledge about the relations of things is 

 deficient, mistaken, or deranged. Thus, one thinks of Eddyism as a 

 delusion which for obvious reasons has had a certain popularity. The 

 delusions' names, like their natures, in the history of civilization have been 

 legion, but With the advancement of learning they continually become 

 fewer and less dangerous. In the individual delusions are of all sorts, 

 all degrees, and all importances. Some of the dearest beliefs the world 

 knows are delusions: surely Santa Glaus is the precious birth-right of 

 every child. 



It is with the delusions at the basis of paranoia (monomania), paresis, 

 etc., that mental and legal medicine are most often concerned. Some- 

 times these are based on hallucinations or on illusions. Whatever their 

 source (and we have no idea of it in pathological terms), the delusions of 

 an alienated mind often make him, long before he is put in a hospital, 

 one of the most dangerous of beings, so cunning and so cruel are the 

 purposes of such unfortunates apt to be under the unnatural stimuli of 

 these delusions. These are unknown derangements in the powers of the 

 reasoning aspects of the mental process. 



Anesthesia. This term commonly means not only the absence of 

 "feeling," as the word itself implies, but also the absence of pain, anal- 

 gesia. In the use of laughing-gas (nitrous oxide), for example, pain may 

 be lost and feeling retained, and this is the case also in the lightest degrees 

 of the effects of ether- and of chloroform-inhalation. Analgesia and 

 anesthesia may be either general or local. In the former case the anes- 

 thetic is inhaled and, entering the circulating blood through the alveolar 

 walls, is taken quickly to every part of the body. It is its action on the 

 nervous system especially which causes the disturbance, shutting off, 

 or "loss" of consciousness. Local anesthetics seem to act by cutting 

 off the else painful impressions passing inward on the afferent nerves. 

 We are concerned now only with general anesthesia, and then only so 

 far as consciousness is concerned. 



General anesthetics in one way or another (just how is not yet certain) 

 check the conductivity in the neural tissue and thus prevent that unifica- 

 tion of numberless impressions which we call the mental process or con- 

 sciousness. People widely vary in their mode of reaction to anesthetics, 

 but very often (aside from the feelings of suffocation, etc., incident to 

 taking the drug) there is experienced a vast hurrying of some great mass 

 that is very variously described. Most often, perhaps, this mass very 

 early begins to rotate, sometimes around the anesthetized subject, 

 sometimes with the latter on its edge, or within it. Then the speed 

 rapidly increases until the mind is in a vortex of tremendous energy but 

 without any suggestions (usually) of terror or unpleasantness. No 

 limit of time can be set by the subject to these long-remembered im- 

 pressions, but often they seem to continue throughout the anesthesia. 



