Module 5: Motor Development & Control. Cerebellum, Basal Ganglia & Movement Flashcards
Function of Cerebellum
- Coordinator & predictor of movement & mediates skilled manipulation of muscles.
- Smooths mov’t
- Influence BS nuclei
- receives sensory info from PNS - compares & integrates info w mov’t plans of cortex
- Important role in processing sensory info & coordination & cognitive & emotional function
- predict consequence of mov’t through feed-fwd ,mechanisms & can modulate ongoing mov’t patterns
Info Travelling through Cerebellar Peduncles
Inferior = Proprioceptive info from upper (cuneocerebellar) & lower (Post spinocerebellar) & vestibular info. (AFFERENT & EFFERENT)
Middle = pontocerebellar (AFFERENT) (Info from cortex via pontine N)
Superior = Anterior spinocerebellar (unconscious proprioception) & auditory & visual info (AFFERENT & EFFERENT)
- All info leaving cerebellum via SCP & ICP
4 paired deep cerebellar Nuclei
= serve as relay & processing stations for info coming from C cortex to targets outside C.
- Festigial (deepest) = Eye mov’t & midline control. Projects to vestibular nuclei & reticular formation
- Interposed Nuclei (Globose & Emboliform) = receive spinal, proximal somatosensory, auditory & visual info. Project to contra red nucleus - origin of rubrospinal tract
- Dentate = fine motor control. Projets to contra red nucleus & VL thalamus
3 functional Zones of Cerebellum?
- Vestibulocerebellum = Vestibular reflexes & upright postural maintenance
- Spinocerebellum = Integration of sensory input w motor commands to produce adaptive motor coordination. output projects to rubrospinal, vestibulospinal & reticulospinal
- Cerebrocerebellum = planning & timing of movements & cognitive functions of cerebellum
Clinical signs & symptoms of poor functioning Cerebellum
- Dysmetria (poor measurement)
- Dysdiadochokinesia
- Dysarthria (issues w language)
- Ataxia (lack smoothness)
- Tremor
- Hypotonia
- poor coordination / clumsy & balance issues
- Late development of milestone
- W sitting
- Stuttering
Clinical Cerebellar tests
Assessing for smoothness/ Rhythm & timing
- Observe = Gait/ tandem/ toe walking (broad based? will fall to side of cerebellar weakness), eye mov’ts, Speech
- Dysmetria (finger-nose. Overshooting?)
- DDK
- Rebound (overshoot?)
- Heel - shin (LL DDK)
- Posture
- Hypotonia
Cerebellar Rehab
ALWAYS START WITH MIDLINE CEREBELLUM
1 = eyes & upright posture / gross
- superman/ ball rocking
- sky diver
- bike riding
- trampolining
2 = Hips & shoulder girdle control
- wheel barrow
- monkey bars
- Bouncing basket ball (side of deficit)
3 = Fine motor
-alternating movements w metronome
Clinical Cerebellum Important in
- Movement = facilitates smooth mov’t by error detection & correction
- Motor learning to create motor patterns
- Posture
- Timing of learned, skilled movements
- cognitive functions
Cerebellar Afferents
- info from cortex via pontine nuclei - pontocerebellar pathway
- Vestibular nuclei
- Spinal cord (ant & post spinocerebellar, cuneocerebellar = non conscious proprioception)
Cerebellar Efferents
- Red nucleus
- Thalamus
- Vestibular nuclei
Olive
Effects of BS wind up/ compromise d/t birth
- vagal nerve affected in high wind up of mid brain;
- Digestive issues
- Poor sleep/ wake regulation
- ## Dural tension
Sutural work affects vagal tone
- Sutural system fires into BS via trigeminocervical nucleus - precursor into vagal system
Cerebellar Lateralisation
L cerebellar deficit = poorly affect R cortex
R cerebellar deficit = Poorly affect l cortex; reduced cognitive skills
POstural Reflexes:
- Head control w pull- sit = develop 1-3 months (elbows should be flexed)
- Positive support = 4 months
- Lateral propping = 6 months
- posterior propping= 10 months
- Plantar/ babinski reflex = disappears 12 months d/t myelination
Signs & symptoms of Hypotonia
- reduced muscle tone = soft/ doughy
- delayed motor milestones/ reflex integration
- problems w feeding
- shallow breathing
- ## Low tone mouth = tongue fwd posture/ out and open
Tests for Hypotonia
- Pull-sit (head lag, elbows extended)
- POSTURE - do they have any extension tone
- Scarf sign (elbow cross midline <12 mo)
- Increased ankle DF
- Reduced MSR
- Poor horizontal suspension/ extension tone
- Poor shoulder girdle tone w vertical suspension
- Heel - ear (extension of knee)
Causes of Hypotonia
- Benign Congenital Hypotonia
- Down’s Syndrome
- Muscular Dystrophy
- Cerebral Palsy
- Prader-Will Syndrome
- Myotonic Dystrophy
-Marfan Syndrome - Tay- sachs disease
Ways to stimulate the Cerebellum & Cortex:
- Firing M spindle cells & joint mechanoreceptors
- Muscle stretch, small joint mobs
- Vestibular input
- Deep Pressure massage
- Playing in gravity
CEREBELLUM - clapping/ w metronome
- single leg balance
- bouncing BB
- Big circular movements
What are the roles of the two functional parts of the Substantia Nigra?
- Pars compacta (SNc)and the surrounding Ventral Tegmental area - contain the dopaminergic melanin pigmented neurons
- Pars reticulata (SNr) - is a basal ganglionic output nucleus
Role of Basal Ganglia?
The integrator of the CNS
- regulates thalamic activity (how much sensory info goes to thalamus) which in turn regulates cortical activity
- BG influence thalamus, thalamus influence cortex
What are the input nuclei of the Basal Ganglia?
(Cortex to BG)
- Striatum (Caudate & Putamen)
- Nucleus Accumbens
What are the output Nuclei of the Basal ganglia?
(BG to Cortex)
- Globus Pallidus internal
- Substantia Nigra pars reticula
Is the thalamus under tonic inhibition?
how can this be changed
- Yes
- output from BG can either increase of decrease tonic inhibition of thalamus via Direct/ indirect pathway
Which pathway releases thalamus from tonic inhibition?
Direct = leads to greater cortical output
What is the dentorubrothalamicortico tract responsible for?
fine movement
