Extrapyramidal System Flashcards
(36 cards)
Pyramidal
primary pathway for voluntary movement
direct activation pathway
Extrapyramidal
responsible for the regulation of reflexes and maintenance of tone and posture
Extrapyramidal System Comprised of:
(subcortex structures)
- basal ganglia (nuclei of the EPS)
- corpus striatum (globus pallidus, putamen, caudate nucleus)
- subthalamic nucleus
- substantia nigra
- red nucleus
- brainstem
- reticular formation
- associated complex interconnecting pathways
Basal Ganglia
- nuclei (main part)
- behind the eyes
- contributes to control of the body’s posture, overall muscle tone, and facilitation/coordination of muscle movements (works w/cerebellum)
Corpus Striatum
(basal ganglia and internal capsule)
initiates and regulates gross, intentional movements of the body
-stimulation of parts of the corupus striatum produce stereotyped movements such as flexion of an entire limb
ESP also controls….
- automaticity of walking and/or running
- cooperation of independent movements of the extremities
- freedom of movements
- suppress unwanted involuntary movements including tremors
Movement Disorders
disprders involving the EPS
examples: Parkinson's disease Sydenham's chorea Huntington's chorea Athrtosis WIlson's disease Tourette's syndrome
Lesions in the basal ganglia my produce:
- various abnormal postures
- confliction between flexion and extension
- facial tics, lip-smacking
- abnormal deglutition
- flailing of the arms
Diffuse lesion in Globus Pallidus and and Corpus Striatum
may result in Athetosis
Degenerative changes in Subthalmic Nucleus
may result in Ballism
Lesions involving Caudate Nucleus
may result in Chorea
Diffuse Basal Ganglia pathology
may result in Dyskinesia
Degenerative changes in Substantia Nigra
may result in tremor
Athetosis
slow twisting and writing movements in muscles of the UE (includes speech muscles; tongue)
Ballism (Hemiballisum) (quick form)
wild flinging movements that usually involve one side of the body (violent)
Quick Form of Dysarthria
- forceful, swinging, jerky, and sudden movements of arms/legs
- one side ofthe body (hemiballism) and is associated with subthalamic nucleus contralateral to the side w/the dyskinesia
Chorea (quick form)
- rhythmis,quick involuntary movements of the muscles in distal extremities (head, neck, face, limbs, and trunk)
- rapid and appear coordinated but are purposeless
- muscles tone can var from hypo to hyper and include extremities and speech musculature
- fatigue can bring on chorea movemnets so rest can help
- movement can increase with increased fatigue and emotional distress
- appears gracefull (dance like)
Dyskinesia
accessory movements associated with a desired motor act
Tremor
rhythmic movements associated with either resting or intention types
resting=substantia nigra
intention=cerebellar
EPS Biochemisrty
- neurons in substantia nigra produce neurotransmitter dopamine
- dopamine=inhibitory
- depletion of domamine results in parkinsonsim
- levadopa or L-dopa may help replenish dopamine and reduce s/s of parkinsonism
- other neurotransmitters may be affectsed by disorders of ESP
Hypokinetic Dysarthria
Perceptual Characteristics- monopitch, reduced stress, monoloudness, inappropriate silences (freezes), short rushes (parkinsons disease)
Localization- ESP
Etiologies- PD, drug induced
Neuromuscular Conditions- slow movements limited ROM, paucity of movements, rigidity, loss of automaticity, resting tremors, pill rolling, immobility
Primary Parkinsonism
idiopathic, degenerative disease of middle age (40-60y)
the term primary refers to the structure or organ
Symptomatic Parkinsonism
occurs secondary to encephalitis, arteriosclerosis, and/or various toxicities such as carbon monoxide and manganese drugs
sympotmatic= “as a result of”
Wilson’s Disease
- inherited disorder, results from excessive amounts of copper collecting in the brain, liver, cornea
- progressive disease of early life
- ataxic-spastic-hypokinetic dysarthria
- impaired muscle tone is usually followed by tremor or athetoid movemnets
- tremors will often precede rigidity or impaired muscle tone
- voluntary movements and deglutition are impaired early and to severe degrees
- can have masked facies, lose emotional control and mild dementia
- psychiatric illness may be present
Kayser-Fleischer Ring
are dark rings that appear to encircle the iris of the eye