Neuroanatomy Chapter 4:
Cerebral Cortex: place where consciousness arises and where voluntary action is initiated.
I.
General Structures and Landmarks of the Cerebral Cortex
a. Cerebral hemispheres: two mirror-image halves of the cerebral cortex
b. Meningeal lining: Membranes that overlay the cerebral cortex, consisting of the dura
mater, arachnoid mater and pia mater. FUNCTION: protects and supports the structure
of the brain. Provides nutrients to the neurons and glial cells.
i. Layers:
1. Dura mater: outermost layer. Comprised of two layers of tough
connective tissue that are tightly bound together.
a. The outer layer is More inelastic than the inner layer
b. Epidural space is the space between the layers
c. 4 infoldings that support and surround the major structures of
the brain
i. Falx cerebelli
ii. Tentorium cerebelli
iii. Diaphragma sallae
d. Subdural hematoma: cerebral blood vessel is ruptured.
2. Arachnoid mater: spider like covering that’s under the dura mater
which many blood vessels of the brain pass
a. Lacey filamentous lining, easily disrupted during dissection.
3. Pia mater: inner most later. Delicately envelops all the sulci and gyri of
the CNS.
a. Contains major blood vessels that serve the surface of the
cerebrum.
c. Gyri: outfoldings
d. Sulci: infoldings
i. Major Sulci and Fissures
1. Superior longitudinal fissure: separates the right and left hemispheres.
2. Precentral gyrus: boundary between the frontal and parietal lobes
3. Lateral fissure/ lateral sulcus/ Sylvian fissure: Separates the temporal
lobe from the parietal and frontal lobes. In swallowing, the buccal
cavity.
e. The Ventricles and Cerebrospinal Fluid
i. Cerebrospinal Fluid: CSF: bathes the CNS, providing a cushion for the neural
tissue, some nutrient delivery and an important waste removal process that
occurs during sleep.
1. Consist of 4 cavities:
a. Lateral Ventricles: Right lateral ventricle, Left lateral ventricle
(largest ventricles)
i. Choroid plexus: produce the bulk of the CSF, although
all of the ventricles produce CSF.
ii. Largest of the ventricles
iii. Four spaces that extend into each of the lobes of the
cerebral cortex. Shaped like a horseshoe
1. Anterior horn of the lateral ventricles projects
into the frontal lobe to the genu of the corpus
callosum.
2. Septum pellucidum: medial wall of lateral
ventricle.
b. Third ventricle ,Fourth ventricle