Natural vs Conditioned Reflexes

What you do

• Remember the wider rule: all reflexes are involuntary, but not all involuntary actions are reflexes.

Challenges to clear

• Fill the conditioned bin. Ask each time whether learning was needed.
• Now sort every reflex.
• Fill the Natural (inborn) reflex column — the responses you were born with.

The task

Each of these is a reflex. Decide whether it came built in at birth or was picked up through experience.

What this lesson covers

• Natural (inborn) reflex — Inherited from the parents, needing no previous experience, and much the same in every human.: Blinking when an object rushes at the eye (A protective reflex present from birth; the eyelids also snap shut when a strong beam of light is flashed across.); Sneezing when an irritant enters the nose (Protective and inborn. No one has to be taught to sneeze.); Coughing when swallowed food enters the wind pipe (Protective and inborn: the cough clears the airway before the food can block it.); Knee-jerk when tapped below the kneecap (The relaxed leg extends involuntarily. The command never reaches the brain; the reflex is settled in the spinal cord.); Salivating while actually chewing food (Saliva flows the moment food is in the mouth. This one provides functional efficiency rather than protection.); Peristalsis pushing chyme along the intestine (The stretching of the intestinal wall is the stimulus and the wave of contraction is the response, entirely inborn.)
• Conditioned (acquired) reflex — Built up during life by learning, and different from person to person.: Pavlov's dog salivating at the bell alone (No animal salivates at a sound naturally. Repeated training paired the bell with food until the sound by itself brought the saliva.); Mouth watering at the smell of a familiar dish (The brain remembers the taste from earlier meals. Had you never eaten that food, the response would not occur.); Standing up when the teacher enters the class (A learned habit. Most of our daily habits and acts are conditioned reflexes.); Tying shoe-laces while talking to someone (So well learned that you no longer know which lace goes over which. A voluntary action repeated often enough turns involuntary.); Playing a musical instrument (Fingers move without conscious choice only after long practice, so this differs from one person to the next.); Braking when someone steps in front of your cycle (Instant and unwilled, yet it exists only because you learned to ride. A person who never cycled has no such reflex.); A dog running away when you kneel down (The dog has learned that kneeling often means a stone is being picked up. Circus animals are trained the same way.)

Hint

Salivation sits in both bins. Chewing food and salivating is inborn; salivating at the mere sight or smell of it is learned. The test is whether the stimulus is the direct one or a substitute you were trained to accept.