Introduction

Question 2

Functions of Pyramidal System (UMN)

Question 3

Functions of Extrapyramidal System

Answer 3

• REGULATION et the voluntary motor activity.
• Regulation of the emotional & associated movements.
• Inbibition of muscle tone.

Question 4

Functions of Cerebellar System

Answer 4

• Co-ordination the voluntary motor activity initiated by pyramidal system.
• Maintenance of equilibrium

Question 5

Functions of LMN

Answer 5

Transmission of the motor impulse from the AHCS to the voluntary muscles.

Question 6

Def of Deep Reflex (Tendon Jerk)

Answer 6

This is an INDUCED (Dynamic) local axon stretch reflex.

Question 7

What is Deep Reflex (Tendon Jerk) Induced by?

Answer 7

It is induced by:

• Sudden stretch of the muscle by tapping the tendon with a hammer.
• This induced sudden stretch will suddenly & temporarily activate the local axon reflex → this will result in sudden transient contraction of the muscle (jerk).

Question 8

Components of Deep Reflex

Answer 8

Question 9

Types of Deep Reflex

Answer 9

• Normal deep reflex (Tendon Jerk).
• Pathological deep reflex.

Question 10

Def of Pathological Reflexes

Answer 10

• reflexes which are normally absent → its presence indicates U.M.N.L. (Don’t elicit them in patient with normal or hyporeflexia)

Question 11

Examples of Pathological Reflexes

Answer 11

adductor, patellar and finger flexion reflexes

Question 12

Effect of Pyramidal System on Deep Reflexes

Answer 12

The deep reflex receives inhibition from the Pyramidal system

Question 13

UMNL & Deep Reflexes

Answer 13

UMNL results in loss of inhibition on the deep reflex, leading to:

• Increased deep reflex (hyperreflexia) below the level of the lesion.
• Appearance of pathological reflexes.

Question 14

LMNL & Deep Reflexes

Answer 14

LMNL results in interruption of the reflex arc, leading to:

• Decreased deep reflex (hyporeflexia) at the level of the lesion.

Question 15

Def of Muscle Tone

Answer 15

This is a SPONTANEOUS (Static) local axon stretch reflex:

Question 16

Why is Muscle Tone spontaneous?

Answer 16

It is spontaneous because:

• The length of any skeletal muscle is shorter than the distance between the origin & the insertion (bone growth is faster than soft tissue growth) → so any muscle is always in a state of persistent spontaneous slight stretch.
• This spontaneous persistent stretch will persistently activate the local axon reflex → this will result in persistent (maintained) contraction of the muscle (tone).

Question 17

Pyramidal & Extrapyramidal system & Muscle Tone

Answer 17

The Muscle tone receives inhibition from the Pyramidal & Extrapyramidal systems

Question 18

UMNL & Muscle Tone

Question 19

LMNL & Muscle Tone

Answer 19

LMNL results in interruption of the reflex arc, leading to:

• Decreased muscle tone (flaccidity) at the level of the lesion.

Question 20

Absent Reflex in Plantar Reflex

Answer 20

Question 21

Def of Fasiculations

Answer 21

oscillatory movements of the muscles caused by an irritating lesion of the AHCs

Question 22

Compare between UMNL & LMNL

Answer 22