3 types of abnormal reflexes: 1) Asymmetry of response
2) Absence of response
3) Persistence of response
Deep tendon reflexes:
• Patellar and achilles
• Can be variable due to the corticospinal pathways not being fully developed
• Asymmetry is more important than degree of presence or exaggeration
Plantar response or Babinski’s sign/reflex:
Stroke plantar surface along outer border with blunt object – a positive response is spreading of the toes with hallux dorsiflexion
Normal from birth to age 6 years (sometimes up to 2 years)
After one year this reflex should not exist – response should be plantarflexion
If persists disorder of pyramidal system
Finger placed in infant’s mouth should initiate sucking reflex
Present from birth - should disappear by 5 months.
Fingers should automatically grasp object placed in had – also foot should respond similarly.
Present up to about age 9 months.