Superficial reflexes

Question 1

corneal reflex

Answer 1

Afferent: Ophthalmic branch (V1) of trigeminal nerve (5th nerve).
Efferent: Facial nerve (7th nerve).
blinking reflex

Question 2

Abdominal reflex (T7-T12)

Answer 2

○ Contraction of superficial abdominal muscles when stroking abdomen lightly (lateral to medial).
○ Significant if asymmetric: Usually signifies a UMN lesion on the absent side.

Question 3

cremasteric reflex (L1,L2)

Answer 3

○ Contraction of cremaster muscle (that will pull up the scrotum/testis) after stroking the same side of superior/inner thigh.
○ Absent with: SCI and corticospinal lesions.

Question 4

Plantar reflex( S1-S2) Tibial Nerve

Answer 4

○ The plantarflexion of toes is elicited when stroking of the lateral sole of the foot from calcaneus to
base of 5th metatarsal.
○ Dorsiflexion of the great toe and fanning of the four small toes: Abnormal or “Babinski Present”,
which is seen with corticospinal/UMN lesions.

Question 5

Anal reflex

Answer 5

○ Reflexive contraction of the external anal sphincter upon stroking the skin around the anus (Afferent:
pudendal nerve; Efferent: S2-S4).

Question 6

Bulbocavernosus reflex

Answer 6

○ Anal sphincter contraction in response to squeezing the glans penis or tugging on an indwelling Foley
catheter.
○ Reflex mediated by S2-S4.
○ It is the first reflex to come after SCI: It is an indicator that the body is out of spinal shock.