Download M555 Medical Neuroscience Lab 1: Gross Anatomy of Brain, Crainal

M555 Medical Neuroscience
Lab 1: Gross Anatomy of Brain, Crainal Nerves and Cerebral Blood Vessels
Anatomical Directions
Terms like “dorsal,” “ventral,” “anterior” and “posterior” provide a means of locating structures
relative to the overall orientation of the nervous system.
Complications with those terms mayarise for two reasons:
i) humans stand upright
ii) the CNS curves or flexes as it grows from the embryonic neural tube,
and the forebrain structures (telencephalon and diencephalon) are oriented somewhat differently
than the brain stem (midbrain, pons, medulla, cerebellum) and spinal cord.
This drawing shows the application of these terms to the human central nervous system.
Forebrain
Orientation
telencephalon
diencephalon
dorsal
superior
rostral
anterior
caudal
posterior
dorsal
rostral
caudal
ventral
midbrain
pons
ventral
inferior
medulla
cerebellum
ventral
dorsal
rostral
ventral
Brain Stem and Spinal Cord
Orientation
spinal cord
rostral
superior
ventral
anterior
dorsal
caudal
dorsal
posterior
caudal
inferior
Axis of CNS
gross neuroanatomical structures and spaces
forebrain
telencephalon
frontal lobe
parietal lobe
temporal lobe
occipital lobe
limbic lobe
insula
lateral sulcus
central sulcus
in the frontal lobe
precentral gyrus
spaces containing
cerebrospinal fluid
lateral ventricles
interventricular foramina
(cerebral) aqueduct
third ventricle
fourth ventricle
central canal (in spinal cord)
anterior commissure
lamina terminalis
arachnoid granulations
(arachnoid villi)
forebrain
diencephalon
pineal
medial surface of the thalamus
medial surface of the hypothalamus
mammillary bodies
in the temporal lobe
superior temporal gyrus
brain stem
transverse gyri
parahippocampal gyrus mesencephalon
tectum
uncus
superior and inferior colliculi
(corpora quadregemina)
in the parietal lobe
tegmentum
postcentral gyrus
substantia nigra
angular gyrus
cerebral peduncles
supramarginal gyrus
pons
pontine nuclei
between the parietal
middle cerebellar peduncle
and occipital lobes
tegmentum
parieto-occipital sulcus
medulla
obex
in the occipital lobe
location of dorsal column nuclei
calcarine gyrus
upper parts of dorsal columns
tegmentum
in the limbic lobe
olives and inferior olivary nuclei
cingulate gyrus
pyramids
corpus callosum
genu, body, splenium
meninges
dura mater
arachnoid and pia mater
(leptomeniges)
cerebellum
lateral hemispheres
tonsils
vermis
cranial nerves
II – XII
olfactory bulbs
and olfactory tracts
optic nerves,
optic chiasm
and optic tracts
arteries
internal carotid As
anterior, middle and
posterior cerebral As
communicating arteries
superior cerebellar A,
AICA and PICA
basilar artery
vestibular arteries
regions of
cerebral cortex
supplied by anterior,
middle and posterior
cerebral arteries
see next page ...
Blood Supply to the Cerebral Cortex
Three major arteries - the Anterior, Middle and Posterior Cerebral Arteries supply the forebrain.
Below are three views of the cerebral hemispheres. On the drawings, identify the regions supplied
by these three major arteries.
anterior
Lateral Surface
of Right Cerebral Hemisphere
anterior
Medial Surface
of Left Cerebral Hemisphere
anterior
lateral
Inferior Surface
of Right Cerebral Hemisphere
Cerebrovascular System
Two systems of arterial blood flow supply the CNS.
- the Internal Carotid System
- the Vertebrobasilar System
Internal Carotid System
Find the remaining part of the Internal Carotid Arteries at the base of the brain.
Anterior Cerebral Artery
Anterior Communicating Artery
Middle Cerebral Artery
Posterior Cerebral Artery
Posterior Communicating Artery
Vertebrobasilar System
Look for the Vertebral Arteries on the brain stem.
Several smaller arteries branch from the vertebral arteries.
Anterior and Posterior Spinal Arteries and the Posterior Inferior Cerebellar Arteries.
Blood from the vertebral arteries enters the basilar artery.
Basilar Artery is found on the ventral surface of the pons, part of the brain stem.
From the basilar artery, blood distributes to
several smaller arteries:
anterior
communicating A
Superior Cerebellar Artery.
Anterior Inferior Cerebellar Artery (AICA).
Posterior Communicating Artery (PICA)
anterior
cerebral A
middle cerebral A
circle of Willis
internal carotid A
posterior communicating A
posterior cerebral A
superior cerebellar A
anterior inferior cerebellar A
posterior inferior cerebellar A
vertebral A
Circle of Willis
A network of arteries in the vicinity of the optic chiasm forms an interconnecting network of vessels.
Blood enters the Circle of Willis from both the Internal Carotid and Vertebrobasilar Systems.
MRIs
Horizontal Views
medulla (top row)
pyramids (approx location)
olive (approx location)
inferior cerebellar peduncle (approx location)
fourth ventricle
cerebellum
vermis
cerebellar hemispheres
pons
pontine nuclei (approx location)
vertebral artieries and basilar artery
insula
Sagittal Views
prime panel: bottom row, left-hand column
corpus callosum – splenium, body and genu
cingulate gyrus and cingulate sulcus
parieto-occipital sulcus
calcarine sulcus
lamina terminalis
thalamus and hypothalamus
mammillary body
brain stem – medulla, pons and midbrain
tectum: superior and inferior colliculi
tegmentum
pontine nuclei (location)
cerebellar tonsil
lateral ventricle, third ventricle, cerebral aqeduct and fourth ventricle
cervical spinal cord
Coronal Views
lateral ventricles and third ventricle
temporal lobe (and uncus)
cingulate gyrus
corpus callosum
cerebellum - vermis and hemispheres
insula