Quiz 2 content (cerebellum, basal ganglia, subcortical white matter, spinal cord and PN) Flashcards
what is the cerebellum best at?
coordination!!!! of ongoing movement
where is the cerebellum located
posterior cranial fossa behind pons and medulla, inferior to occipital lobe
tentorium cerebelli separates
the cerebellum from the occipital lobe
what is this
vermis
spinocerebellum
(vermis and paravermal regions) integrates proprioceptive info
precentral gyrus –> cerebellum for coordination –> to person
cerebrocerebellum
(lateral hemisphere) coordinates precise distal voluntary movement
coordination of fine distal movements
vestibulocerebellum
(flocculonodular lobe; flocculus and nodulus) integrates visual and vestibular input to coordinate motor activities for posture, head, and eye movements
coordination of head and eye movements
where is the olive located?
in the medulla
what kind of cells are a part of the cerebellar cortex?
purkinje cells
what do purkinje cells do?
fan out; connect to other dendrites
how does the cerebellum attach to the brainstem?
through the peduncles (superior, middle, and inferior)
the midbrain connects to the cerebellum through…
superior peduncle
the pons connects to the cerebellum through…
middle peduncle
the medulla connects to the cerebellum through…
inferior peduncle
blue
anterior lobe of cerebellum
red
superior, middle, and lower peduncles
orange
posterior lobe of cerebellum
green
nodulus
blue
vermis
red
anterior lobe
green
posterior lobe of cerebellum
green
superior cerebellar peduncle
blue
middle cerebellar peduncle
red
inferior cerebellar peduncle
yellow
flocculus
pink
cerebellar tonsils
purple
nodulus
what is floccular nodular node made up of?
flocculus and nodulus
red
vermis
orange
paravermis
green
lateral hemisphere
corticospinal tract is…
motor activity of fine movements
functional divisions of the cerebellum
equilibrium; gross movements of the limbs; fine, distal, voluntary movements
equilibrium is regulated by the
vestibulocerebellum (flocculonodular lobe)
gross movements of the limbs are coordinated by the
spinocerebellum (receives proprioceptive info from muscle spindles and control ongoing movement through motor tracts and lower motor neurons)
fine, distal, voluntary movements are coordinated by the
cerebrocerebellum (lateral hemispheres)
vestibulocerebellum: receives input from, sends output to, and function
vestibular apparatus, vestibular nuclei
vestibular nuclei
coordinate eye and head movements
spinocerebellum: receives input from, sends output to, and function
spinal cord, vestibular nuclei
vestibular nuclei, reticular nuclei, motor cortex
neck and postural muscles, gross limb movements
cerebrocerebellum: receives input from, sends output to, and function
cerebreal cortex
motor cortex, red nucleus
lateral corticospinal tract (fine movements), rubrospinal tract (extend wrist and fingers)
cerebellar ataxia
drunken gait, uncoordinated movement
intentional tremors
ex: want to grab a cup and they start shaking
dysdiadochokinesia
automatic movement (supination vs pronation)
- not able to coordinate
dysmetria
ex: reach too far/short for an object (distance problem w/ muscles)
dysarthria
speech muscles affected
decomposition
movement is broken up, glitchy
paravermal lesions result in
gait and limb ataxia
lateral cerebellar lesions result in
hand ataxia
lesions to vermal and flocculonodular lobe result in
truncal ataxia/gait ataxia, nystagmus
ipsilateral lesion (if one side is damaged)
it crosses over to other side but then crosses back over when coming back down
cerebral cortex lesion is (contralateral or ipsilateral)
contralateral
cerebellum lesion is (contralateral or ipsilateral)
ipsilateral
basal ganglia
group of nuclei
*group of cell bodies
red
caudate body
orange
subthalamic nucleus
green
substantia nigra
blue
caudate tail
purple
globus pallidus internus
pink
globus pallidus externus
yellow
caudate head
grey
putamen
caudate and putamen make up the
striatum
putamen and globus pallidus make up the
lentiform nucleus
basal ganglia releases
dopamine
input nuclei of basal ganglia
caudate and putamen (striatum), subthalamic nuclei
output nuclei of basal ganglia
substantia nigra pars reiculata and globus pallidus internrus (GPi)
motor functions of basal ganglia
initiation of movement (green lights)
suppression of unwanted movements (red lights)
non-motor functions of basal ganglia
decision making, judgment, prioritizing information, emotional processing and responses, learning, eye movements, selecting desired behavior, preventing undesired behavior
what are the 5 cortico-basal ganglia-thalamic loop
goal directed behavior
social behavior loop
emotion loop
motor loop
oculomotor
non motor circuits
goal directed behavior, social behavior, and emotion loop
motor circuits
motor loop (direct and indirect pathway)
oculomotor loop
ALL loops go through
basal ganglia
goal directed behavior loop
mainly short term memory
evaluating information for making decisions, planning and choosing actions
head of caudate
lateral prefrontal cortex
social behavior loop
appropriate behavior
ventral prefrontal cortex
personality
recognizes social cues, regulates self control
emotion loop
responsible for integrating emotion and facial expression, seeking rewards, predictions when outcome is unknown, addictions
basal ganglia stroke - depression, emotional blunting
medial prefrontal cortex
oculomotor loop
body of the caudate is part of an oculomotor loop
makes decision about spatial attention and eye movements
motor loops are important for
planning and programming of movement by selecting and inhibiting specific motor strategies
initiation of movement
direct motor pathway
initiation of voluntary movement
go pathway
cortex to putamen to globus pallidus to thalamus and back to cortex
indirect motor pathway
BG involves the GPe, subthalamic nucleus, GPi, substantia nigra reticuclata
suppresses unwanted movements
NoGo pathway
Subcortical white matter is
all white matter consists of myelinated axons
Subcortical WM fibers are put into 3 categories
projection fibers, commissural fibers, association fibers
projection fibers extend
from subcortical structure to the cerebral cortex
all travel through internal capsule
parts of internal capsule
anterior limb, genu, posterior limb
commissural fibers
connect homologous areas of the cerebral hemispheres
(corpus callosum is the largest
callosotomy
done for seizures, surgically removed; prevents excessive firing from spreading
Association fibers
connect cortical regions within one hemisphere (short and long)
short association fibers connects
adjacent gyri
long association fibers connect
lobes within one hemisphere
cingulum connects which cortices
frontal, parietal, and temporal lobe
uncinate fasciculus connects
frontal and temporal lobe cortices
superior longitudinal fasciculus connects
cortices of all lobes
inferior longitudinal fasciculus connects
temporal and occipital lobes
what are meninges
layers that protect spinal cord and brain
(dura, arachnoid, and pia mater)
dorsal root + ventral root =
spinal nerve
divides into dorsal and ventral ramus
contains both motor and sensory
dorsal horn processes
sensory information
ventral/anterior horn processes
motor information
lateral horn processes
autonomic information
how many spinal cord segments are there for each section of the spine (C, T, L, S, C)
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
spinal nerves are named for…
the vertebral level where they exit the vertebral canal
collection of nerve roots inferior to the spinal cord within the bony canal
cauda equina
spinal nerves carry
all motor, autonomic and sensory axons of a single spinal segment
UE myotomes: C1-2
cervical flexion
UE myotomes: C3
cervical side-bend
UE myotomes: C4
scapular elevation
UE myotomes: C5
GH abduction
UE myotomes: C6
elbow flexion
UE myotomes: C7
elbow extension
UE myotomes: C8
thumb abduction
UE myotomes: T1
5th finger extension
LE myotomes: L1-L2
hip flexion
LE myotomes: L3
Knee extension
LE myotomes: L4
ankle dorsiflexion
LE myotomes: L5
Great toe extension
LE myotomes: L5-S1
plantar flexion
LE myotomes: S1-S2
plantar flexion and eversion
Dura mater
tough outer layer
arachnoid mater
separated from pia by cerebrospinal fluid in the subarachnoid space
pia mater
closely adheres to the spinal cord surface
epidural space
between dura and vertebrae
subdural space
between arachnoid and dura
subarachnoid space
between arachnoid and pia
peripheral nerves
including all neural structures (axons of sensory, motor, and autonomic neurons) distal to the spinal nerves
cutaneous branches of peripheral nerves
supply the skin and subcutaneous tissues, including sensory and autonomic related information
muscular branches of peripheral nerves
supply the muscles, tendons, and joints
endoneurium
separates individual axons
perineurium
surrounds bundles of axons (fascicles)
epineurium
encloses the entire nerve trunk
spinal nerve lesions are tested with
myotomes/dermatomes
(ex: C8 spinal nerves lesion)
peripheral nerve lesions are tested with
MMT and muscles
(ex: median nerve lesion)
