The Cerebrum Flashcards
Where is the cerebrum located?
Within the anterior and middle cranial fossa of the cranium. It extends from the frontal bone to the occipital bone and is located above the tentorium cerebelli inferoposteriorly.
What types of tissue is the cerebrum composed of?
White matter - located deep within the brain - made up mainly of myelinated axons.
Grey matter - makes up the cortex on the brain - contains main cell bodies and few mylelinated axons.
External structure - What are the depressions of the cerebrum known as?
Sulci
External structure - What are the elevations or ridges known as?
Gyri
What is the name of the gap that separates the two cerebral hemispheres?
The longitudinal fissure that lies in the median saggital plane.
What structure separates the two cerebral hemispheres?
The falx cerebri, a fold of dura mater.
What structure holds the two cerebral hemispheres together?
What type of fibre is it?
The corpus callosum - commisural fibres.
What are the main sulci?
1) Central sulcus - separates the frontal and parietal.
2) Lateral sulcus - separates the frontal and parietal lobes from the temporal lobe.
3) Lunate sulcus - groove located in the occipital cortex.
What are the main gyri?
1) Precentral gyrus - ridge anterior to the central sulcus - location of motor cortex.
2) Postcentral gyrus - ridge posterior to central sulcus - location of primary somatosensory cortex.
3) Superior temporal gyrus - ridge inferior to lateral sulcus - primary auditory cortex is located here.
What are the main lobes of the cerebrum?
Location?
Function?
1) Frontal lobe - separated by the central and lateral sulci - responsible for higher intellect, personality, mood, social conduct and language.
2) Parietal lobe - separated by the central and parieto-occipital sulcus - responsible for language, calculation and visuospatial functions.
3) Temporal lobe - separated by the lateral sulcus - responsible for memory, language and hearing (primary auditory cortex).
4) Occipital lobe - rests upon the tentorium cerebelli - the parieto-occipital separates the occipital from the parietal and temporal anteriorly. Responsible for vision (primary visual cortex).
What is the arterial supply of the cerebrum?
3 distinct paired arterial branches:
1) Anterior cerebral arteries - supplies anteromedial of cerebrum.
2) Middle cerebral arteries - supplies the lateral portions of the cerebrum.
3) Posterior cerebral arteries - supplies the medial and lateral sides of cerebrum posteriorly.
What is the venous drainage of the cerebrum?
Drainage via small cerebral veins into dural venous sinuses - endothelial linings between the inner and outer layers of the dura mater.
Clinical relevance - cerebrovascular accident
Also known as stroke - this is the abrupt loss of focal brain function lasting more than 24 hours to either spontaneous haemorrhage in brain substance or inadequate blood supply to part of the brain ie. ischaemia (due to thrombosis or embolism). Symptoms can vary depending on which part of the brain is affected.
