Poly Synaptic

Question 1

What is the Inverse Stretch Reflex?

Answer 1

The Inverse Stretch Reflex, also known as the Golgi Tendon Reflex, is a protective reflex that prevents muscle damage by causing relaxation of the same muscle when there is marked tension.

Question 2

What is the stimulus for the Inverse Stretch Reflex?

Answer 2

The stimulus is a marked increase in tension or stretch within the muscle.

Question 3

What are the receptors involved in the Inverse Stretch Reflex?

Answer 3

The receptors are Golgi tendon organs located at the junction of the muscle and tendon.

Question 4

What is the afferent pathway for the Inverse Stretch Reflex?

Answer 4

The afferent pathway involves myelinated Ib nerve fibers that carry the signal to the spinal cord.

Question 5

What is the center for the Inverse Stretch Reflex?

Answer 5

The reflex is processed in the spinal cord and is bisynaptic, involving a single inhibitory interneuron.

Question 6

What is the efferent pathway for the Inverse Stretch Reflex?

Answer 6

The efferent pathway involves α-motor neurons that inhibit (hyperpolarize) the same muscle.

Question 7

What is the response in the Inverse Stretch Reflex?

Answer 7

The response is the relaxation of the same muscle, preventing excessive tension.

Question 8

What is the purpose of the Inverse Stretch Reflex?

Answer 8

It prevents muscle tearing by reducing excessive tension and provides feedback to the brain for motor control.

Question 9

What is the Flexor Withdrawal Reflex?

Answer 9

The Flexor Withdrawal Reflex is a polysynaptic spinal reflex that withdraws a limb in response to a painful stimulus.

Question 10

What is the stimulus for the Flexor Withdrawal Reflex?

Answer 10

The stimulus is an injurious or painful stimulus.

Question 11

What are the receptors involved in the Flexor Withdrawal Reflex?

Answer 11

The receptors are free nerve endings that detect pain.

Question 12

What is the afferent pathway for the Flexor Withdrawal Reflex?

Answer 12

The afferent pathway involves Aδ nerve fibers that carry the signal to the spinal cord.

Question 13

What is the center for the Flexor Withdrawal Reflex?

Answer 13

The reflex is processed in the spinal cord and involves multiple synapses (polysynaptic).

Question 14

What is the efferent pathway for the Flexor Withdrawal Reflex?

Answer 14

The efferent pathway involves α-motor neurons that cause contraction of the flexor muscles.

Question 15

What is the response in the Flexor Withdrawal Reflex?

Answer 15

The response is the flexion and withdrawal of the limb away from the injurious stimulus.

Question 16

What are the properties of the Flexor Withdrawal Reflex?

Answer 16

1. Reciprocal inhibition: contraction of flexors and relaxation of extensors. 2. Crossed extensor reflex: extension of the opposite limb to support body weight if the stimulus is severe enough.

Question 17

What is the Plantar Reflex?

Answer 17

The Plantar Reflex is a polysynaptic spinal nociceptive reflex modified by the corticospinal tract.

Question 18

How is the Plantar Reflex tested?

Answer 18

Stroke the lateral part of the sole of the foot with a sharp object from the heel towards the little toe, then medially along the bases of the toes.

Question 19

What is the normal response in the Plantar Reflex?

Answer 19

The normal response is plantar flexion of the big toe and flexion and adduction of the other toes (flexor plantar reflex).

Question 20

What is the abnormal response in the Plantar Reflex?

Answer 20

The abnormal response is dorsiflexion of the big toe and extension and abduction (fanning) of the other toes, known as Babinski reflex.

Question 21

What does the Babinski Reflex indicate?

Answer 21

The Babinski Reflex indicates dysfunction of the corticospinal tract and can occur in conditions such as cerebral hemorrhage, brain or spinal cord tumors, coma, general anesthesia, deep sleep, or in children up to one year old.

Question 22

What is the Positive Supporting Reaction?

Answer 22

The Positive Supporting Reaction is a reflex that converts a limb into a rigid column to support body weight in response to deep pressure on the sole of the foot.

Question 23

What is the stimulus for the Positive Supporting Reaction?

Answer 23

The stimulus is deep pressure on the sole of the foot.

Question 24

What is the response in the Positive Supporting Reaction?

Answer 24

The response is the contraction of flexors and extensors to form a rigid column.

Question 25

What are the Superficial Abdominal Reflexes?

Answer 25

The Superficial Abdominal Reflexes involve contraction of abdominal muscles in response to scratching the skin of the abdomen with a blunt object.

Question 26

What is the stimulus for the Superficial Abdominal Reflexes?

Answer 26

The stimulus is scratching the skin of the abdomen with a blunt object.

Question 27

What is the response in the Superficial Abdominal Reflexes?

Answer 27

The response is contraction of abdominal muscles: upper abdominal muscles (T7-T9) and lower abdominal muscles (T10-T12).

Question 28

What is the Cremasteric Reflex?

Answer 28

The Cremasteric Reflex is a superficial reflex involving the contraction of the cremaster muscle and elevation of the testis.

Question 29

What is the stimulus for the Cremasteric Reflex?

Answer 29

The stimulus is scratching the skin of the upper inner aspect of the thigh.

Question 30

What is the center for the Cremasteric Reflex?

Answer 30

The center lies in the L1-L2 spinal cord segments.

Question 31

What is the response in the Cremasteric Reflex?

Answer 31

The response is the contraction of the cremaster muscle, causing elevation of the testis.