Cerebellum

Front 1

what seperates the anterior lobe from the posterior lobe?

Back 1

primary fissure

Front 2

what fiber types travel through the superior, middle, and inferior cerebellar peduncles?

Back 2

efferent, afferent, and both

Front 3

describe the path of the vestibulocerebellar tract.

Back 3

from the vestibular nuclei at the borders of the medulla and caudal pons, through the inferior cerebellar peduncle and to the vestibulocerebellum (flocculonodular lobe)

Front 4

describe the path of the posterior spinocerebellar tract. What kind of info does it give the cerebellum?

Back 4

fibers sensing proprioception synapse in the cord and then go up the tract which is in the lateral faniculli through the inferior cerebellar peduncle and to the spinocerebrum (vermis and paravermis) as well as deep nuclei.

Front 5

what is the general path of the corticopontocerebellar tract?

Back 5

comes down the cerebrum to synapse in the ipsilateral basillar pons then through the middle cerebellar peduncle to the contralateral cerebellum.

Front 6

describe the olivocerebellar tract pathway and the name of the fibers in the cerebellum from this tract?

Back 6

from the olive and cross at the inferior cerebellar peduncle and then to the inferior cerebellar peduncle to the entire cerebellar cortex and deep nuclei. These fibers are called climbing fibers while all other input fibers are called mossy fibers.

Front 7

all output from the cerebellar cortex is initiated by what? what NT do they use and where do they first synapse?

Back 7

purkinje cells that use GABA and are thus inhibitory. Purkinje's in the vermis area go to the fastigial nucleus (involved with axial and proximal limb muscles), paravermis to the nucleus interpositus (involved with distal limb muscles), and cerebrocerebellum to the dentate nucleus (involved with SKILLED movement of any type)

Front 8

the output of the cerebellum goes where?

Back 8

motor cortex (via VL relay in thalamus), reticular formation, superior colliculus, vestibular nuclei and red nucleus

Front 9

output that travels to the motor cortex takes what path?

Back 9

cerebellar cortex to the deep cerebellar nuclei to the VL of thalamus to the motor cortex

Front 10

what mechanisms does the cerebellar cortex use to refine each movement?>

Back 10

inhibitory mechanisms

Front 11

what are the three layers of the cerebellar cortex and their functions?

Back 11

the molecular layer is the outer layer that is made up of fibers running all over; the purkinje cell layer is in the middle which are the single layer of "fat cells" that are the projection neurons; the granular layer contains the excitatory granule interneurons

Front 12

in the cortex what is the path of the mossy fibers? the climbing fibers?

Back 12

up granule cells to the molecular layer where they run as fibers until they hit the dendritic tree of a purkinje cell; to the dendritic tree and all around it (1 climbing fiber per 200,000 mossy fibers on each purkinje thus the climbing fibers have enormous influence)

Front 13

long term potentiation uses what? depression?

Back 13

mossy fibers, climbing fibers

Front 14

high skilled movements are programmed where?

Back 14

in the cerebrocerebellum

Front 15

what are the general concepts of cerebellum lesions?

Back 15

loss of muscle coordination and slowness of movement, ipsilateral effects to lesion (unless it is rostral to the pons), possible hypotonia and pendular reflexes, dysarthria (speech defects) in bilateral lesions, slow growing lesions may exhibit few deficits, and static lesions often exhibit improvement

Front 16

what are the signs and symptoms of cerebellar lesion?

Back 16

ataxia, asynergia (loss of synergistic movement), adiadochokinesia (inability to perform rapid, alternating movements), dysmetria (inability to gauge distance), and decompostion of movement (movement broken down into its component parts)

Front 17

what are symptoms of lesions to the vestibulocerebellum?

Back 17

loss of balance and equilibrium, trunkal ataxia, ataxic gait, sway when sitting, nystagmus, nausea, vomiting, dizzines, normal or decreased muscular tone (note that these are very hard to distinguish from loss of vestibular function)