INTRACRANIAL TENSION 43 



and in cases of cerebral involvement, e.g., the intracranial 

 haemorrhage of birth palsies. Cerebral symptoms induced 

 reflexly by pathological conditions of other organs are not 

 accompanied by any increase in intracranial tension. 



Sinking of the anterior fontanelle indicates a decrease in 

 Intracranial tension. It marks a diminution of vitality, and 

 is of common occurrence in epidemic enteritis and other 

 conditions which are accompanied by a loss of fluid from 

 the body. 



The anterior fontanelle should be closed by the end of the 

 second year. Delayed closure occurs in certain constitutional 

 diseases, e.g. rickets, cretinism, etc., or it may be due to 

 hydrocephalus or some other condition causing increased 

 intracranial tension. If the anterior fontanelle closes too 

 early, the condition of microcephalus results. 



The Structure of the Spinal Medulla is identical with the 

 structure of the brain, but the arrangement of its constituent 

 parts is somewhat different. The grey matter is situated 

 centrally and consists of anterior &D& posterior columns (horns] ; 

 the white matter, which consists of afferent and efferent 

 tracts, completely surrounds the grey matter (Fig. 25). 



The posterior funiculus (columns of Goll and Burdock) of 

 the spinal medulla lies between the posterior column of grey 

 matter and the middle line. It contains a few tactile fibres 

 and the fibres which convey joint and muscle sense. These 

 latter arise in the nerve-cells in the ganglia on the posterior 

 nerve-roots of the spinal nerves and ascend, through the 

 spinal medulla, to the medulla oblongata, where they establish 

 connexions with the cerebellum. Above the level of the 

 decussation of the pyramids, they cross the median plane 

 and ascend through the pons and mid-brain to reach the 

 thalamus. Their precise destination is not yet known, but 

 they probably traverse the posterior part of the posterior 

 limb of the internal capsule. 



In advanced cases of locomotor ataxia, joint-sense and 



