Sketchy Path: Neuro - "Spinal Muscular Atrophy, Amyotrophic Lateral Sclerosis (ALS) & Friedreich Ataxia"

Question 1

The upper motor neurons pass through the ___________ tracts of the spinal cord.

Answer 1

pyramidal (like the pyramids on the robot’s shoulders)

Question 2

In a cross section of the spinal cord, the upper motor neurons are in the _____________ tract.

Answer 2

corticospinal (postero-lateral)

Question 3

LMNs exist in the _____________ part of the spinal cord.

Answer 3

anterior horn

Question 4

Review the symptoms characteristic of UMN injuries.

Answer 4

• Hyperreflexia (large reflex hammer)
• Clasp-knife rigidity (clasped knife on back of ranger)
• Babinski sign – upgoing plantar reflex (toes going up)

Question 5

Review the symptoms characteristic of LMN injuries.

Answer 5

• Hyporeflexia (left side of robot dropping reflex hammer)
• Hypotonia (limp fingers)
• Atrophy (shriveled left arm)
• Fasciculations (shaking arm)

Question 6

Spinal muscular atrophy attacks ______________.

Answer 6

the anterior horn LMNs (like the two anterior horns on the Spiny Muscular Space Worm)

Question 7

Werdnig-Hoffman refers to what subtype of SMA?

Answer 7

Type I infant-onset (like the baby WoRms)

Question 8

SMA has what type of inheritance?

Answer 8

AR (like the receding guy behind the car)

Question 9

In contrast to SMA, poliomyelitis causes ___________ atrophy.

Answer 9

asymmetric

Question 10

Amyotrophic lateral sclerosis attacks which cells?

Answer 10

UMN and LMN (like the Green Gehrig monster sending out vines to attack the rangers and the top of the robot)

Question 11

ALS is associated with ___________ of the distal extremities.

Answer 11

asymmetric atrophy (like the one shriveled arm of the Green Gehrig monster)

Question 12

What enzyme is often defective in those with ALS?

Answer 12

Superoxide dismutase (SOD-1)

Think of the SOD sign near the feet of the Green Gehrig monster.

Question 13

____________ has been shown to delay the progression of symptoms in those with ALS.

Answer 13

Riluzole (like the ranger RILing the sOiL)

Question 14

Friedreich’s ataxia is what kind of mutation?

Answer 14

• Autosomal recessive (guy receding behind FRAT house)
• Loss-of-function in frataxin (torn FRAT shirt)
• Trinucleotide GAA repeat

Question 15

Frataxin is in what organelle?

Answer 15

Mitochondria (like the mitochondrial door)

It is involved in iron elimination. Without it, iron oxidizes in the mitochondria (like the rusting weights outside the frat house).

Question 16

Neurologically, Friedreich’s ataxia affects _______________.

Answer 16

the dorsal columns and the spinocerebellar tracts

Think of the cracked columns and the kid tripping.

Question 17

What non-nervous system organs are affected in Friedreich’s ataxia?

Answer 17

• Spinal scoliosis (bent telephone pole)
• Heart (bagpipe player symbolizing hypertrophic cardiomyopathy)
• Diabetes (frat brother tossing candy)