802 Psychoses. 



chronic disseminated distemper encephalitis, and in the parrot a traumatic lesion of 

 the brain, v. Kaliseher has proved experimentally that injury of a definite part of 

 the mesostriatum in parrots abolishes their power of speech. 



In a case observed by Pierquin a previously healthy and very lively young cat 

 was attacked with something like an "anxiety psychosis"; the animal became as 

 if fascinated at the first sight of a dog; it watched the dog with anxious look, was 

 motionless and stupid, and recovered only after several hours, the dog having been 

 removed in the meantime. In this case there appears to have been simply a violent 

 fright of a more than usually sensitive animal, similar to that in the so-called ' ' faint- 

 ing goats" (see page 77.5). 



In this category would also belong the mad rush of a herd of animals (taking 

 fright in a body, stampede, animal panic). But there is no valid reason for con- 

 sidering these as acute psychoses, because in such stampedes it is less an un- 

 thinking factor, the sensing of a danger and the transmission of this idea upon 

 all individuals of a herd, that is here active, but rather reactions to external in- 

 fluences, based upon instinct (Dexler). Stampedes, especially in horses, and not sel- 

 dom in cattle, camels and mules are not rare moreover, and may be very fatal in the 

 course of war or manoeuvres. The impetus to a stampede is apparently always af- 

 forded by the abnormal excitement of one or several individuals and finally it causes 

 an unreasoning flight in which the animals run blindly against obstacles or precipitate 

 themselves into fire or water, etc. A blind, unreasoning flight is now and again 

 noticed in single animals. 



Straaten saw paroxysmal attacks of nervous symptoms in 12 cows of different 

 herds after a severe fright. These were manifested by shaking of the head, stagger- 

 ing, falling down, stretching of the limbs, loud bellowing, labored breathing and 

 diarrhea. In half an hour the attack was over. 



To the affective psychoses especially melancholy, a case is supposed to belong 

 which was observed also by Pierquin in a dog. An old dog went about sorrowfully 

 after the death of his master, took insufficient food and finally became affected with 

 marasmus, dying in a few months. Neither during life nor after death were the 

 various organs examined for any derangement, and therefore internal illness leading 

 to nutritional disturbances was not eliminated. 



The three cases of psychic paralysis in dogs recorded by Aruch (1889) exhibit 

 a great similarity to disturbances caused by compression of the spinal cord. Nor 

 can exact proof be deduced from the case of supposed psychic paralysis in an 

 epileptic horse, recorded by Girotti, since no anatomical examination was made. 



Albrecht (1903) reports upon nervous disturbances in a dog whose extensor 

 muscles of the fore and hind limbs together with the muscles of mastication refused 

 to act after certain influences. By strong stroking or tapping of the back, the dis- 

 turbances were made to disappear. When these attacks became more and more 

 frequent, the dog finally became incapable of standing upright, and fell away rapidly 

 in condition. As the examination of the brain gave negative results (the spinal cord 

 was not examined) a psychic illness with pronounced symptoms of inhibition was 

 supposed to have been present. 



Staggers of horses was in many instances mistaken for a kind of "circular 

 delirium." Gleisberg (1865) says in his text book of Comparative Pathology, that 

 ' ' idiopathic delirium ' ' among animals, especially horses, is represented by staggers ; 

 he identified the socalled mad staggers with the paroxysms of "idiopathic de- 

 lirium." On the other hand, Vogel (1888) grouped the maniacal symptoms together 

 under the name of "mania transitoria" and considered them to be due to organic 

 disease of the brain, nervous predisposition, sexual excitement and so forth. Ziirn 

 (1899) agrees with Gleisberg 's view concerning staggers in horses, and Hoffmann 

 (1899) also classes staggers and restiveness with the mental diseases without, however, 

 attempting an analysis of the symptoms. Finally, even a prominent psychiatrist like 

 Ferg (1895) considers that staggers of horses is very similar to the "mental con- 

 fusion" of man. But if one considers that the circular delirium of man in the ma- 

 niacal stage is characterized by a hilarious ill-temper and by acceleration of cortical 

 association, and in the melancholy stage, by morbid primary depression, primary 

 inhibition of thought and frequently also by motor inhibition (Ziehen), the idea of 

 allying staggers with the psychoses in man that have been mentioned, will have to 

 be given up, the more so, as staggers is based upon organic brain disease. 



By many authors the disseminated subacute or chronic encephalitis of distemper 

 has been taken to be dementia paralytica (paralysis progressiva). In a case de- 

 scribed by Cadiot (1896) in a three year old dog, previously very lively, which had 

 been forgotten in a railway carriage and in consequence made a journey of 79 hours' 

 duration, a certain idiocy developed after a few weeks, while a two year old dachs- 

 hund observed by Nissl, suddenly became ill with nervous symptoms. Both cases 

 call to mind the appearances of distemper encephalitis, and the histological changes 



