3 88 



THE BRAIN 



The arteries of the ant ero -lateral central group are very numerous. They 

 pierce the substantia perforata anterior and supply the lentiform nucleus, 

 the internal capsule and the external capsule, the caudate nucleus, and a 

 portion of the thalamus. 



The cortical branches supply the greater part of the 

 supero-lateral surface of the hemisphere, the lateral half of 

 the orbital surface, the lower surface of the interior part of 

 the temporal lobe and the temporal pole (Figs. 147, 148). 



The frontal and parietal branches turn round the upper lip of the 

 posterior ramus of the lateral fissure and ascend on the supero-lateral 

 surface of the hemisphere. The frontal branches are : ( I ) lateral orbital, 



Ascending parietal artery Central sulcu 



Ascending frontal artery 

 Precentral sulcus 

 Inferior frontal 

 sulcus 



Parieto-temporal artery 



Superior 

 frontal 

 sulcus 



Parieto- 



occipital 



fissure 



(Lateral 



part) 



Inferior lateral frontal 

 artery 

 Posterior ramus of lateral fissure 



Temporal branches 



FIG. 148. Supero-lateral surface of the Cerebral Hemisphere. The districts 

 supplied by the three cerebral arteries are tinted differently : anterior 

 cerebral, purple ; middle cerebral, blue ; posterior cerebral, red. (Semi- 

 diagrammatic. ) 



to the lateral part of the orbital surface of the frontal lobe ; (2) inferior 

 lateral frontal, to the inferior and middle frontal gyri ; (3) ascending frontal ', 

 which runs upwards in relation to the anterior central gyrus (Figs. 147, 148). 



The ascending parietal branch extends, in an upward and backward 

 direction, in relation to the posterior central gyrus, and its terminal twigs 

 supply the greater part of the cortex of the superior parietal lobule (Fig. 187). 



The parieto -temporal branch is a very large artery which issues from 

 the posterior part of the posterior ramus of the lateral fissure ; it sends 

 branches upwards to the inferior parietal lobule, and others which incline 

 downwards over the posterior part of the temporal lobe. Its twigs, as 

 a rule, do not encroach upon the supero-lateral surface of the occipital 

 lobe (Fig. 148). 



The temporal branches, two or three in number, issue from the posterior 

 ramus of the lateral fissure, and, turning downwards and backwards, over 

 its lower lip (i.e. the superior temporal gyrus), they ramify upon the 

 lateral surface of the temporal lobe (Fig. 148). 



