Reflex system

Question 1

What are the constituents of a reflex arch

Answer 1

• receptor
• afferent nerve
• reflex centre (intercalated neuron)
• efferent nerve
• effector

Question 2

Why are reflexes so important to the diagnosis and localisation of neurological lesions

Answer 2

because each reflex has its own reflex arch

Question 3

What are the 3 categories of reflexes

Answer 3

• superficial reflex
• deep reflex
• pathological reflex

Question 4

What is a superficial reflex

Answer 4

a rapid muscle contraction response when the superficial receptors in the skin or mucous membrane are stimulated

Question 5

List the 5 main superficial reflexes

Answer 5

1. Corneal reflex (Pons: VI,VII)
2. Pharyngeal reflex (medulla oblongata: IX,X)
3. Abdominal reflex
   upper: T7-8
   middle: T9-10
   lower: T11-12
4. Cremasteric reflex (L1-2)
5. Plantar reflex: (S1-2)

Question 6

What is a deep reflex

Answer 6

a rapid muscle contraction response when the deep receptors in the muscle or tendons are stimulated

Question 7

List the 4 main deep reflexes

Answer 7

1. Bicep’s reflex (C5-6)
2. Tricep’s reflex (C6-7)
3. Knee jerk reflex (L2-4)
4. Ankle reflex (S1-2)

Question 8

What are pathologic reflexes

Answer 8

Refer to Babinski sign that only occur when there are lesions in the UMN