THE BRAIN AND CRANIAL
NERVES SUMMARY
, Chapter 14 - The Brain and Cranial Nerves
14.1 - Overview of the Brain
Major Landmarks
rostral - toward the
forehead o anterior
caudal - toward the spinal cord
o posterior
coronal - (or frontal) sectioning into ventral-dorsal planes
sagittal - sectioning from left to right
brain weighs about
o 1,600 g (3.5 lb) in men, and
o 1,450 g in women
3 major portions of the brain:
o cerebrum - is 83% of brain volume
cerebral hemispheres,
gyri and sulci,
longitudinal fissure,
and corpus callosum
o cerebellum - contains 50% of the neurons
second largest brain region
located in posterior cranial fossa
o brainstem - the portion of the brain that remains if the cerebrum and cerebellum are
removed diencephalon,
midbrain,
pons, and
medulla oblongata
longitudinal fissure - deep groove that separates cerebral hemispheres
gyri - thick folds
sulci - shallow grooves
corpus callosum- thick nerve bundle at bottom of longitudinal fissure that connects hemispheres
,the brain occupies the
o anterior cranial fossa,
o middle cranial fossa, and
o posterior cranial fossa
cerebellum occupies posterior cranial fossa
o marked by gyri, sulci, and fissures
separated from cerebrum by transverse cerebral
fissure o about 10% of brain volume
o contains over 50% of brain neurons
2
, brainstem - what remains of the brain if the cerebrum and cerebellum are
removed o major components:
midbrain
pons
medulla oblongata
3
NERVES SUMMARY
, Chapter 14 - The Brain and Cranial Nerves
14.1 - Overview of the Brain
Major Landmarks
rostral - toward the
forehead o anterior
caudal - toward the spinal cord
o posterior
coronal - (or frontal) sectioning into ventral-dorsal planes
sagittal - sectioning from left to right
brain weighs about
o 1,600 g (3.5 lb) in men, and
o 1,450 g in women
3 major portions of the brain:
o cerebrum - is 83% of brain volume
cerebral hemispheres,
gyri and sulci,
longitudinal fissure,
and corpus callosum
o cerebellum - contains 50% of the neurons
second largest brain region
located in posterior cranial fossa
o brainstem - the portion of the brain that remains if the cerebrum and cerebellum are
removed diencephalon,
midbrain,
pons, and
medulla oblongata
longitudinal fissure - deep groove that separates cerebral hemispheres
gyri - thick folds
sulci - shallow grooves
corpus callosum- thick nerve bundle at bottom of longitudinal fissure that connects hemispheres
,the brain occupies the
o anterior cranial fossa,
o middle cranial fossa, and
o posterior cranial fossa
cerebellum occupies posterior cranial fossa
o marked by gyri, sulci, and fissures
separated from cerebrum by transverse cerebral
fissure o about 10% of brain volume
o contains over 50% of brain neurons
2
, brainstem - what remains of the brain if the cerebrum and cerebellum are
removed o major components:
midbrain
pons
medulla oblongata
3
