# 13 - F. Cerebrospinal fluid

# F. Cerebrospinal fluid

© SPMM Course 
VII 
Facial 
Both sensory and motor. Transmits taste sensation and controls facial muscles 
VIII 
Vestibular 
Transmits auditory sensation 
 
Cochlear 
Transmits balance sensation 
IX 
Glossopharyngeal 
Motor control of pharynx; parasympathetic control of the parotid gland; taste from the back of 
the tongue. 
X 
Vagus 
Motor control of larynx and pharynx; parasympathetic control of the viscera; visceral 
sensations. 
XI 
Accessory 
Motor control of neck muscles 
XII 
Hypoglossal 
Motor control of tongue muscles 
 
E. Spinal Cord 
Unlike cerebrum where grey matter is on the outer surface, in spinal cord grey matter occupies the deeper 
aspect forming an H shaped column surrounding the CSF. The white matter bundles form anterior, lateral 
and dorsal columns around the grey matter zone. The dorsal column carries proprioceptive sensory fibres; 
the anterior and lateral columns are made of ascending spinothalamic tracts carrying touch, pressure, 
pain and temperature sensations. 
F. Cerebrospinal fluid 
CSF is secreted by the choroid plexus in the lateral, third and fourth ventricles and at a rate of 300 ml/day, 
which is almost protein free. 
Route: From lateral ventricle to 3rd ventricle via interventricular foramina of Monroe; From 3rd to 4th 
ventricle via cerebral aqueduct of Sylvius; From 4th ventricle to subarachnoid space via foramen of 
Magendie (single) and foramina of Luschka (two lateral). 
The body of the lateral ventricle lies immediately below the corpus callosum, and the two lateral ventricles 
are separated by septum pellucidum. The third ventricle lies between thalamus and hypothalamus. The 
fourth ventricle lies above the pons and just below the cerebellum. 
Obstruction to CSF circulation commonly occurs within third or fourth ventricle (foramen of Monroe), 
leading to non-communicating hydrocephalus. Impairment of CSF reabsorption in the subarachnoid 
space due to partial occlusion of the arachnoid villi leads to communicating hydrocephalus.