Exam 2 - cerebellum Flashcards
cerebellum embryonic development
metencephalon
function of lateral hemispheres
input
output
initiation, planning, timing of complex movements
motor cortices
motor cortices
vermis and paravermal zone function
input
coordination of voluntary movement
unconscious proprioception (4 spinocerebellar tracts + trigeminocerebellar tracts)
function of the flocculonodular lobe
input
output
coordination of equilibrium and vestibular reflex; influences vestibular motor tracts (MLF & LVST)
vestibular apparatus & vestibular nuclei
UMN systems - vestibular nuclei via purkinje cell projections
layers of the cerebellum
molecular layer
purkinje/pyriform layer
granular layer
function of the purkinje/pyriform layer
afferent info?
inhibitory to deep cerebellar nuclei and vestibular nuclei
afferent info = unconscious proprioception, vestibular info, motor planning
the function of the deep cerebellar nuclei
all output from the cerebellum emanates originates from these nuclei
spinocerebellar tracts function, fibers, synapse, ipsilateral or contralateral
brings unconscious proprioceptive info from trunk/limbs to cerebellum
Aalpha fibers (fast, myelinated)
one synapse
ipsilateral
rostral spinal cerebellar tract
neck/forelimbs/craniothoracic trunk
cuneocerebellar tract
neck/forelimbs/craniothoracic trunk
dorsal spinocerebellar tract
hindlimbs/caudal trunk
ventral spinocerebellar tract
hindlimbs/caudal trunk
trigeminocerebellar tract
head (face/mouth)
signs of cerebellar disease
motor ataxia
dysmetria/hypermetria
tremors **hallmark of CD
truncal sway
increased muscle tone
pendular or vestibular nystagmus
loss of menace reaction
NO paresis/paralysis or abnormalities of sensation
cerebellar hypoplasia
common cause?
incomplete development of cerebellum
feline panleukopenia virus “distemper” or BVD
In this course, you will probably be repeatedly told that the cerebellum “modulates the rate, range, and force of voluntary movement.” Be prepared to explain in detail what that phrase means.
cerebellar output to UMN systems
vestibular nuclei –> LVST
red nucleus –> rubrospinal tract
motor cortex –> cortical motor tracts
how are the functions of the cerebellum accomplished?
adjusting output of UMN pathways
