Intro to neuroanatomy Flashcards
CNS
Brain
Spinal cord
Components of brain
cerebrum
cerebellum
basal ganglia
brain stem
components of spinal cord
spinal tracts
meninges
axial skeleton
PNS
cranial nerves
major plexuses
all other nerves
What is the most complex region of human anatomy
CNS
what has more structures/regions in a smaller area than any other part of the body
brain
what does embryology start with —-
neural tube
what is the neural tube created from
ectoderm
when is the neural tube formed
between 2nd and 4th week after conception
The neural tube differentiates into 3 regions
forebrain
midbrain
hindbrain
Forebrain
telencephalon
diencephalon
cerebrum (basal ganglia and amygdala)
thalamus
hypothalamus
Midbrain
midbrain lol
Hindbrain
metencephalon
myelencephalon
When is the neural tube fully closed
by 6 weeks; and ventricles are formed
When does the PNS begin a period of rapid growth
8 weeks
When are all major components of the brain present
by around 34 weeks
brain development does not stop until approximately 25 years
White matter
myelinated structures in the CNS that appear white
primarily myelinated axons
Gray matter
unmyelinated structures such as neuronal cell bodies, dendrites, and some axons
Nuclei
collection of nerve cell bodies in the CNS
Edinger-Westphal nuclei
Ganglia
collections of nerve cell bodies in the PNS
sympathetic chain ganglia
What is the exception to the ganglia/nuclei concept
Basal ganglia –> found in the CNS (should be called nuclei)
Rostral
towards the nose/beak
Caudal
towards the tail; sacrum
Dorsal
towards the back
Ventral
towards the front
What is the largest part of the brain by weight
cerebrum
Cerebrum
contains outer cortex and inner subcortical white and gray matter
Subcortical white matter
corpus callosum
Subcortical gray matter
basal nuclei
Cerebral cortex
the outer gray matter layer of the cerebrum
4 lobes based on geography (frontal, parietal, occipital, temporal)
Where do subarachnoid bleeds occur
arachnoid trabeculae
Which meninge is the strongest
Dura mater (it’s durable!)
Meninges (in order)
Dura mater
Arachnoid mater
Pia mater
Folds of the dura mater for the
falx cerebri
falx cerebelli
tentorium cerebelli
The basal ganglia are
subcortical nuclei
5 paired nuclei
5 paired nuclei
caudate
putamen
globus pallidus
subthalamic
substantia nigra
Basal ganglia functions
fine tune voluntary movement
middleman between cortex and pyramidal system
also plays a role in limbic system –> mood, motivation, reward, fight/flight
Where is the amygdala found
the end of the caudate nucleus
strongly associated with aggression, particularly in association with fight/flight
White matter tracts
myelinated axon tracts that connect different gray matter regions
3 types
3 types of white matter tracts
projection
commissural
association
Association white matter tract
connect areas in the same hemisphere
Commissural white matter tract
connect areas in different hemispheres
corpus callosum
Projection white matter tract
connect cerebrum to other areas in CNS
internal capsule (corona radiata)
Thalamus
paired gray matter region with up to 50 isolated nuclei
relay station for sensory and motor function
Hypothalamus
found anterior-inferiorly to the thalami
11 major nuclei found here
main function: homeostasis (body temp, metabolism, alertness, reproduction, sleep)
What does the hypothalamus impact many of its functions through
pituitary gland
Midbrain location
found inferiorly to the thalamus and hypothalamus
Midbrain associated structures
colliculi
cerebral peduncles
Midbrain functions
eye movement
transmit fibers of ascending and descending spinal tracts
auditory and visual reflexes
Superior colliculus
visual reflexes
Inferior colliculus
auditory reflexes
Cerebral peduncle
transmits spinal tracts to pons and rest of brainstem
Key structures of hindbrain
pons
medulla
cerebellum
Structures of the brain stem
midbrain
pons
medulla
Cerebellum
little brain
subconscious fine motor coordination
attached to the cerebrum, pons, and medulla via the cerebellar peduncles
Pons
middle part of brainstem
sleep wake cycle
transmits spinal tract axons (afferent and efferent)
regulates breathing in conjunction with medulla
also affects BP and HR
Where does the basilar artery lie
basilar groove
Medulla
final part of brainstem (final connection to the spinal cord)
Structures of the medulla
pyramids
olive
decussation
Pyramids
contain the corticobulbar and corticospinal tracts (motor)
Olive
muscle memory and coordination
Decussation
Corticospinal tract decussates here
Spinal cord travels from
foramen magnum –> L1/2
Key structures of spinal cord
lumbar and cervical enlargement
cauda equina
spinal nerve roots
meningeal layers