BIO 371 Lecture 3 Exam

What are the anatomical divisions of the cerebellum?

Flocculonodular lobe, anterior lobe, posterior lobe

What are the functional divisions of the cerebellum?

Vestibulocerebellum, spinocerebellum, pontocerebellum

What’s part of the vestibular nuclei?

Saccule, utricle, & semicircular nuclei

What’s part of the vestibulocerebellum?

Inner ear, flocculonodular lobe, fastigial nucleus

→ Balance

What’s part of the spinocerebellum?

Anterior lobe, globus, emboliform nuclei

→ Unconscious propioception

What’s part of the pontocerebellum?

Posterior lobe, pontocerebellum, dentate nucleus

→ Speed, duration, force

From where does the pyramidal system rise from?

Cerebral cortex

What is the motor system arising from the cerebral cortex coined?

Pyramidal system

What regulatory structures are termed the extrapyramidal system?

Cerebellum and certain basal nuclei

What are the cerebellum and basal nuclei termed as?

Extrapyramidal system

What muscles are the general visceral efferent or autonomic nervous system in charge?

Involuntary - smooth muscle, cardiac muscle, glands

Where is the sympathetic division located at?

T1-L2 in the LGH

Where is the parasympathetic division located at?

CN III Ocumolotor, CN VII Facial, CN IX Glossopharangyeal, CN X Vagus, S2-S4 in the LGH

What is the sympathetic in charge of?

Fight or flight

What is the parasympathetic in charge of?

Rest & digest

What muscles are the special visceral efferent in charge?

Muscles in head region

What muscles are the general somtaic efferent in charge?

Muscles in trunk and limbs

What are the cortical components of the pyramidal system?

BN 4; BN 6,8; BN 3,1,2; BN 5,7; BN39,40; UMN

What are the subcortical components of the extrapyramidal system?

Basal nuclei(caudate, putamen, globus pallidus)

Cerebellum

VAN & VLN

Subtantia nigra

Red nucleus

Vestibular nuclei

Reticular formation

Subthalamic nuclei

How many axons cross over at the pyramidal decussation to the contralateral side as the lateral corticospinal tract?

85-90%

How many axons do not cross over continuing ipsilaterally as the ventral corticospinal tract?

10-15%

Axons in the ventral corticospinal tract help with what?

Control neck and shoulder muscles, primary neck reflex

What makes up the corpus striatum?

Caudate & putamen

What makes up the lenticular nucleus?

Globus pallidus & putamen

Lesions in the subtantia nigra cause what?

Parkinson’s disease

What does the substantia nigra produce?

Dopamine

What are symptoms of parkinson’s disease?

Rigidity of musculature

Akinesia

Resting tremor

Fixed expression/limited emotional expression

Patient stands with stooped posture and walks with shuffling steps

Festinating gait

Akinesis paradoxica

What is akenisia?

Difficulty initiating and performing voluntary movements

What is festinating gait?

Pace of walking, once started, becomes more rapid

What are choreiform movements?

Rapid, irregular series of movements

What is a fatal genetic disease that degenerates the caudate nucles called?

Huntington’s chorea

What is huntington’s chorea charactirized by?

Progressive dementia, choreiform movements

When do symptoms for huntington chorea begin?

30 to 40s

What is a temporary condition caused by rheumatoid fever from streptococcus called?

Syndenham’s chorea

What is syndenham’s chorea also called?

St. Vitus dance

What is hemichorea?

Movement confined to one side of the body

What causes hemichorea?

Vascular lesion to contralateral to basal nuclei

What disorder is caused by damage to the globus pallidus?

Athetosis

When does athetosis occur?

Damage to the globus pallidus, CO poisoning, (in cerebral palsy patients) brain damage at birth due to hypoxia

What are the characteristics of athetosis?

Slow, writhing “snake-like” movements of extremities, neck, and trunk

What disorder is caused by damage to the subthalamic nuclei?

Hemiballismus

What is hemiballismus characterized by?

Onset of wild flinging motions of upper and lower limbs on one side of the body

What latrogenic disorder is caused by exposure to too much dopamine over a long period of time?

Tardive dyskinesia

In what patients is tardive dyskinesia common in?

Patients using L-DOPA for parkinson’s disease or antipsychotic drug Haloperidol

What are early symptoms of tardive dyskinesia?

Lip-smacking & cheek-puffing

What are symptoms of tardive dyskinesia?

Unwanted face, neck, and arm movements

Lip-smacking

Cheek-puffing

What usually causes lesions to the flocculonodular lobe?

Tumors in children especially medulloblastoma

What are symptoms of lesion to the flocculonodular lobe?

Disturbances in balance and stance

Truncal ataxia

Patient stands with feet apart

Nystagmus

What is truncal ataxia?

Trunk sways back and forth

What is nystagmus?

Rapid oscillations of the eyes when looking forward

What often causes lesions to the anterior lobe?

Alcoholism

What are symptoms of lesion to the anterior lobe?

Uncoordinated movements in upper and lower limbs

Uncoordinated gait

Why is there uncoordinated gait in lesions to the anterior lobe?

Lower limb is usually more affected than upper limbs

What commonly causes lesions to the posterior lobe?

CVAs, neurodegenerative diseases, trauma, tumors

What are symptoms of lesions to the posterior lobe?

Ataxia

Disturbance of stance

Dysarthria

Dysmetria

Dysdiadochokinesis

Asynergy

Hypotonia

Intention tremor

What is ataxia?

Unsteady gait

What is dysarthria?

Slow, slurred speech

What is dysmetria?

Disturbance in judging where to stop a trajectory movement, overshooting a target

What is dysdiadochokinesis?

Inability to perform rapid, alternating movements

What is asynergy?

Lack of smooth transition between components of a movement

What is hypotonia?

Decreased muscle tone and decreased resistance to joint manipulation

In what disorder is intention tremor usually seen in?

Lesions to the posterior lobe

In what disorder is resting tremor usually seen in?

Parkinson’s disease

What does UMN lesion in the brain or spinal cord cause?

Spastic paralysis

Muscles can be contracted through reflex arc but without regulation of movement from the brain in spastic paralysis.

True or false

True

What are symptoms of spastic paralysis?

Hyperreflexia

Clonus movements

Mild to moderate atrophy of muscles that are paralyzed

What is hyperreflexia?

Uncontrolled and exaggerated movements

What are clonus movements?

Alternate rapidly between contracting and relaxing in response to passive stretching

What does a babinski reflex indicate?

A lesion in the pyramidal motor system

What is a babinski reflex?

Abnormal dorsiflexion of the big toe when the sole of the foot is stroked

What do lesions in the LMN (ventral root) in the PNS cause?

Flaccid paralysis

In flaccid paralysis since the LMNs are intact the reflex arc is not lost and muscles can contract.

True or false

False

Since LMNs are not intact the reflex arc is lost and muscles cannot be contracted

What are the symptoms of flaccid paralysis?

Areflexia

Severe atrophy

What is areflexia?

Reflex arc is lost and muscles cannot be contracted

What is paralysis of one limb called?

Monoplegia

Right or left upper monoplegia, or lower monoplegia

What is paralysis of both limbs on one side of the body called?

Hemiplegia

Right or left hemiplegia

What is paralysis of both lower limbs called?

Paraplegia

What is paralysis of all four limbs called?

Quadriplegia or tetraplegia

What is shingles?

A reoccurrence of varicella zoster, chicken pox

What is shingles also called?

Herpes zoster

During the initial infection for shingles, where does the virus move?

Into the DRG of spinal nerves and/or the sensory ganglia of cranial nerves and becomes dormant

Especially in which cranial nerve does shingle initially becomes dormant in?

CN V, trigeminal

When does shingles reactivate? And, what happens?

During stress or immune suppression. It infects a single dermatone. Very painful “chicken pox” type lesions appear on dermatone supplied by affected nerve ganglion.

What are symptoms of shingles?

Bumps

Vesicles or blisters

High fever

Fill with lymph and break open

Lesion crust over

Postherpetic neuralgia

What is postherpetic neuralgia?

Damaged nerves

What happens if the shingles virus affects the trigeminal nerve?

Lesions appear on face and may occur in eye and in mouth. If in cornea, it may lead to blindness.

Where does herpesvirus move once activated?

It moves retrograde in sensory neurons axons to a specific dermatone.

Does polio affect sensory?

No

Does polio affect motor?

Yes

In what patients is polio usually seen in?

Non-immunized people, especially illegal aliens

Where is polio still a problem?

Third world countries, more at risk include Pakistan and Afghanistan

When was the last case of “wild” polio in the US?

1979

How does the polio virus enter the body?

Through the digestive tract in contaminated food or water. Enters the cell bodies of LMNs in VGH.

How does polio lead to flaccid paralysis?

Virus kills Giant Multipolar neurons

How does polio affect limbs in adults versus children?

Children → One limb is affected

Adults → Paralysis in both arms and/or both legs

What may a person who recovered from polio develop after 10-40 years?

Post-polio syndrome

What are symptoms of post-polio syndrome?

Muscle weakness, fatigue, breathing problems, muscle and joint pain

What is the disease called?

It has similar symptoms to polio and can occur at any age, usually older adults. LMNs are affected first, leading to muscle weakness in one or more extremities to muscle wasting and atrophy.

Amyotrophic lateral sclerosis (ALS)

What is amyotrophic lateral sclerosis also called?

Lou Gehrig’s disease

Where does ALS eventually spread to?

To UMN and travels up spinal cord through the pyramidal tract to cerebral cortex.