brain + spinal cord
CNS =
cranial & spinal nerves
PNS nerves eg.
PNS
are cranial nerves part of the CNS or PNS
cranial nerves
most superior nerves of the PNS
somatic + autonomic
PNS =
sympathetic + parasympathetic
autonomic =
sympathetic
fight & flight
parasympathetic
rest & digest
somatic
voluntary control
autonomic
involuntary control
somatic
spinal nerves, cranial nerves & association nerves are part of somatic or autonomic ?
oligodendroglia
makes myelin in CNS
schwann cells
makes myelin in PNS
cell bodies + dendrites
grey matter =
axon + myelin
white matter =
grey matter
white matter
sensory, affective, motor, effective
SAME =
CNS to PNS
motor neurons travel .....
PNS to CNS
sensory neurons travel
motor neurons
what cells are myelinated
CNS to CNS
interneurons travel....
PNS
lower motor neurons located in ....
CNS
upper motor neurons located in...
an effector (muscle)
a lower motor neuron's axon terminates on....
another neuron
an upper motor neuron's axon terminates on.....
thalamus
thalamus
important for integrating modalities
pons
medulla
midbrain
Midbrain + Pons + Medulla
brainstem
gyri
bulges =
sulci
grooves =
cerebrum
corpus callosum
cerebellum
central sulcus
central sulcus
separates frontal & parietal lobes
nuclei
small collection of neurons in the CNS
ganglia
small collection of neurons in the PNS
tract
axon-fibre bundle
cerebellum
coordination of smooth muscle movement
corpus callosum
white matter fibre crossing; important for interconnecting the left and right hemispheres of the brain
frontal lobe
temporal lobe
occipital lobe
parietal lobe
pre central gyrus
post central gyrus
sylvian fissure
horizontal
neutron layers in cerebral cortex are arranged in horizontal/vertical layers
6
how many layers of cells in the cerebral cortex
1. molecular layer, 2. external granular layer, 3. external pyramidal layer, 4. internal granular layer, 5. internal pyramidal layer, 6. multiform layer
layers of the cerebral cortex in order
layer 5, internal pyramidal layer
what layer does the pyramidal tract originate from
80-90, 10-20
_____% of cells in the cerebral cortex are pyramidal & ______% are non-pyramidal (stellate or granule)
brodmann area 4; primary motor cortex
brodmann areas 1, 2, 3; somatosensory cortex
brodmann area 17; primary visual cortex
brodmann areas 41, 42; primary auditory cortex
brodmann areas 44, 45; broca's area
brodmann area 22; Wernicke's area
brodmann area 39; angular gyrus
primary motor cortex
brodmann area 4 =
somatosensory cortex
brodmann areas 1, 2, 3 =
primary visual cortex
brodmann area 17
primary auditory cortex
brodmann area 41, 42
Broca's area
brodmann area 44, 45
Wernicke's area
brodmann area 22
angular gyrus
brodmann area 39
primary motor cortex & supplementary motor cortex
part of the cerebral cortex that corticospinal & corticobulbar tracts originate from
RHS
LHS of the body controlled by _____of brain
LHS
RHS of the body controlled by _____ of brain
hand, arm & face
Broca's area is immediately adjacent to the part of the motor cortex responsible for moving
Broca's aphasia
deficit in language production; can understand speech but cannot produce it; expressive aphasia
expressive aphasia
Broca's aphasia =
receptive aphasia
Wernicke's aphasia =
expressive & receptive aphasia
global aphasia =
angular gyrus
reading & writing comprehension
primary motor cortex
part of the cortex responsible for initiating voluntary movement
somatosensory cortex
part of the cortex responsible for sensory processing
primary visual cortex
calcarine cortex =
primary auditory cortex
Heschl's gyrus =
wernicke's area
comprehension of written and spoken language
Wernicke's aphasia
lack of understanding of what is being spoken/written
corticospinal & corticobulbar
2 tracts in the pyramidal system
corticobulbar tract
cortex --> brain stem
corticospinal tract
cortex --> spine
corticospinal tract
projects to spinal nerves
corticobulbar tract
projects to cranial nerve nuclei
place of decussation
pyramids
two elongated swellings on the ventral aspect of the medulla
lateral
the corticospinal axons that decussate continue their descent in the ........ corticospinal tract
anterior
the corticospinal axons that DO NOT decussate continue their descent in the ........ corticospinal tract
contralateral motor deficits
damage to the corticospinal fibres rostral to the pyramidal decussation results in.....
ipsilateral motor deficits
damage to the corticospinal fibres caudal to the pyramidal decussation results in.....
right hemiplegia
a lesion of the left corticospinal tract in the internal capsule (rostral to pyramidal decussation) results in.....
hemiplegia
same side paralysis =
hemiparesis
same side weakness
NO
if corticospinal or corticobulbar tract get lesions; do the muscles atrophy ?
YES
if neurons in the ventral horn of the spinal cord that directly innervate muscles die/get lesions do the muscles atrophy ?
atrophy of muscle; cannot contract
death of LMN =
spastic paralysis, increase in muscle tone & rigidity due to increased excitation
if UMN is damaged but LMN is intact =
proximal muscles
anterior corticospinal tract neurons innervate....
limb muscles
lateral corticospinal muscles innervate...
ischemic stroke
stroke that occurs when the flow of blood to the brain is blocked by the narrowing or blockage of blood vessel or by a clot
embolic stroke
a type of ischemic stroke that causes a clot to travel to the brain and lodge in narrower brain arteries, mostly from the left side of the heart
Haemorrhagic stroke
faulty blood vessel bleeds into the brain; causes death of neurons around it
Multiple Sclerosis
demyelination of the CNS neurons; causes inappropriate pattern of firing
monoplegia
paraplegia
tetraplegia
movements of the right hand
a stroke which causes damage in the left primary motor cortex; what is most likely to be affected
movements of the left hand
a motorcycle accident causes damage to the left lateral corticospinal tract
conduction aphasia
aphasia that occurs from damage to the arcuate fasciculus; can understand written and spoken language but difficulty repeating words
alexia
cannot read, but can write; damage to visual cortex area
word deafness
corpus callosum affected; deaf to the meaning of heard words
corpus callosum
damage to what area causes word deafness
visual cortex
damage to what area causes alexia
arcuate fasciculus
damage to what area causes conduction aphasia
middle cerebral artery
what artery is the most common site of occlusion & stroke ?
middle cerebral artery
artery that supplies the largest area of the brain