Somatic Motor Control Flashcards
Where are UMN localised
CNS
Where are the bodies of LMN found and where do they project to?
Ventral grey horn. Periphery
What cortical later are UMN found
Pyramidal layer V
Neurotransmitters used by UMN
GABA
Glutamate
The two tracts used by UMN
Corticospinal
Corticobulbar
Describe the lay out of UMN in primary motor cortex
Medial areas associated with limbs
Lateral areas associated with face.
Larger cortical areas for finer movements such as hands and fingers due to more UMN needed
Name the cortical areas responsible for movement
Prefrontal : planning
Supplementary : initiation
Precentral: execution
Post central and posterior parietal: sensory perception and representation of space
Name the topography of body part innervation in caudate striatum
Cerebral peduncle
Cervical cord
Peduncle (face becomes more medial) And caudate Face Arm (int) Trunk (int) Leg (lat)
FATL
cervical cord
Arm (medial)
Trunk (int)
Leg (lat)
Which corticospinal tract carried limb info and which for trunk
Include fiber %
Lateral limbs 80
Anterior trunk 20
Briefly explain what the extra pyramidal motor tracts do
Retucul: posture and tone
Vestibular : posture and balance
Tectospinal: colliculus
Rubro: wrist and hands (instant DECUSSATE on at nucleus)
Where does the rubrospinal tract terminate at?
Cervical (brachial plexus)
Name the vestibulospinal divisions
Medial : neck
Lateral: lumbar region. Deep extensors of back
Where does the corticospinal tracts project to?
Basal ganglia Thalamus Red nucleus Pontine Reticuloformation Inferior olive Pyramids
Vestibulospinal is unconscious but not involuntary
👍🏻
Describe the DECUSSATions of corticospinal tract
Lateral decusates at pyramids
Anterior decussates at level of spinal cord synapse
What will a LMN always cause ?
A contraction
How is the topographical mm innervation lay out in spinal cord
Trunk and prolximal mm on anteromedio grey horn
Distal limbs more anterolateral grey horn
Where do LMN get re organised
Plexus
Describe the relationship between muscles and LMN
A LMN will one rate a cluster of muscle fibers meaning LMN innervating a single muscle are all grouped in columns in the anterior grey horn
Describe the reaction process in spinal cord
Sensory info into the dorsal horn, synapse at interneuron , sends an efferent straight to the anterior horn.
Cause mm reflex. (No cortical efferent, but sensory info will reach brain)
THE EFFERENT REACTION WILL SYNAPSE BOTH CONTRA AND IPSI SO BALANCE CAN OCCUR DURING RELFEX ACTION
What is a central pattern generator? And where are they found ?
Spinal cord and brain stream
A reflex (but not really thought as one) as we walk we are instantly balancing and moving but we don’t think about how we walk. It’s unconscious
What occurs if lesion you dorsal horn occurs ?
Sensory loss and paint and temp at contra lateral side
What occurs if a lesion to ventral horn happens
Loss of LMN motor output
What is a radiating reflex and Babinski associated with ?
UMN DAMAGE
What type of damage causes peripheral nerve damage ?
Physical or chemical
Is LMN lesion contra or ipsi ??
Ipsi
Name symptoms associated to LMN like polio
Ipsilateral Weakness or paralysis Flaccid muscles Atrophy Reflexes reduced or abolished
Symptoms of UMN lesion (eg stroke)
Weakness or paralysis
Less atrophy (LMN Infact)
Increased spacitity due to loss of inhibitory actions of UMN on LMN
Also increased or exaggerated reflexes
Is UMN lesion ipsi or contra
Mainly contra in medulla, ipsi below
Motor neuron disease (Lou gerhigs)
Neurodegenerative (both UMN and LMN)
Muscle atrophy
Paralysis
Cognitive functioning intact
