Anatomy of the Motor system

Question 1

Name the three types of fibres in the cortex

Answer 1

projection fibres, association fibres and commisural fibres

Question 2

which fibres are in the :

1. corpus callosum
2. corona radiata

Answer 2

1. commisural fibres

2. projection fibres

Question 3

path of the corticobulbar tract

Answer 3

UMN projection fibres from cortex through genu ( geniculate fibres) in internal capsule to the cranial nerves

Question 4

path of corticospinal tract

Answer 4

UMN projection fibres from cortex through posterior limb of the internal capsule. two tracts
ventral - supplies the trunk, synapse to LMN in the spinal cord
lateral - decussates in the spinal cord and supplies the limbs, synapses to LMN

Question 5

Where are UMN cell bodies

Answer 5

layer 5 of the primary motor cortex (internal pyramid layer)

Question 6

symptoms of UMN syndrome

Answer 6

weakness, stiffness of CONTlateral muscle
exaggerated reflex - babinski, spasticity , clonus
hypotonia

Question 7

describe:

1. primary lateral sclerosis
2. pseudobulbar palsy
3. cerebal palsy
4. multiple sclerosis

Answer 7

ALL UMN diseases

1. CS tract degen - rare, late onset
2. CB tract degen - problems with speaking, chewing, swallowing
3. damage to UMNs in developing brain. not progressive - problems with coordination/ spasticity
4. inflammation destroying myelin. - stiffness, spasticity, coordination speech

Question 8

describe

1. progressive muscle atrophy
2. progressive bulbar palsy
3. spinal muscular atrophy

Answer 8

ALL LMN diseases

1. degen LMN - rare, early onset, 5 yr survival rate
2. degen specific LMN, - cranial nn
3. genetic, effects LMN

Question 9

Describe

1. charcot-marie-tooth-disease
2. guilan-bar-syndrome

Answer 9

1. inherited neuropathic disorder, progressive

2. immune attack peripheral nn , in responce to infection 80% likelihood of recovery