General Symptomatology of Diseases of the Brain. 585 



duration and after its disappearance the particular disturb- 

 ances are aggravated. 



Giddiness is a frequent symptom of disease of the brain and 

 usually results from a temporary loss of consciousness. 



Abnormal movements are seen in both acute and chronic 

 conditions. They may be associated with loss of consciousness 

 and may affect either the whole body or only a part in the form 

 of tonic-clonic spasms (eclamptoid or epileptiform cases), and 

 also there may be forced movements and ataxia. 



Both the frequence and rhythm of the respiration may be 

 altered. _ In complete loss of consciousness and in deep stupor 

 the respirations are deep and their frequence diminished. In 

 severe cerebral diseases respiration of the Cheyne-Stokes type 

 is not rarely observed. In this type of breathing after a num- 

 ber of respirations of different lengths there is a pause which 

 may last for several seconds to be followed by respirations 

 which at first are superficial and which gradually become deeper 

 and even dyspneic. This is followed by another pause and the 

 respirations become gradually shallow again. In other cases of 

 encephalitis and meningitis respiration of the Biot type is ob- 

 served. In this type a number of normal respirations are fol- 

 lowed by a long pause. Another type of respiration is also ob- 

 served in which a long pause follows a series of respirations 

 which are at first violent and gradually decrease. As a general 

 rule any serious change in the type of respiration is an un- 

 favorable point in connection with prognosis. 



Changes in the rapidity of the pulse are frequently ob- 

 served. In diseases in which there is an increase of intracranial 

 pressure stimulation of the vagus slows the pulse rate, but 

 should there be any other factor in operation, such as fever, ex- 

 citement, heart weakness, which has an accelerating effect on 

 the pulse, stimulation of the vagus is without effect. In some 

 cases of serious disease of the brain there is acceleration of the 

 pulse which is of the utmost importance, as there are no other 

 factors tending to produce this in operation. In all these cases 

 the pulse may also be irregular. Considerable variations of the 

 number and rhythm of the pulse are observed in cases of 

 meningitis. 



Vomiting is seen frequently in carnivora and swine in cases 

 of diseases of the brain, and especially in acute meningitis and 

 is due either to direct stimulation of the vomiting center or of 

 the sensory nerve fibers of the meninges. The vomiting center 

 in the other animals is far less sensitive to stimulation and, as 

 a rule, they do not vomit in cerebral diseases. 



According to some authors (Esberg, Lustig) venous con- 

 gestion of the papilla of the optic nerve is caused by increased 

 intracranial pressure and especially in cases of chronic dropsy 

 of the ventricles. This should not be of very rare occurrence 

 in animals, but the majority of veterinary authors have not ob- 



