Answer: A reflex action is a quick, automatic, involuntary response to a stimulus, controlled by the spinal cord or brain. Based on previous experience reflexes are unconditioned (inborn) and conditioned (acquired).
Reflex action: a spontaneous, automatic and involuntary response of an effector (muscle or gland) to a stimulus, without the conscious involvement of the brain. The pathway is the reflex arc: receptor → sensory neuron → spinal cord/brain (interneuron) → motor neuron → effector.
Types based on previous experience:
- Unconditioned (inborn) reflex: present from birth, not learned and does not need any previous experience. Example: withdrawal of the hand on touching a hot object, blinking of eyes, knee-jerk reflex, sucking by a newborn.
- Conditioned (acquired) reflex: developed during life by learning, repetition and previous experience. Example: secretion of saliva at the sight or smell of tasty food (Pavlov’s dog salivated at the sound of a bell), cycling, typing or playing a musical instrument without thinking.
