Once when juanita gave blood, she became very dizzy and passed out. now whenever she sees a needle, she starts feeling dizzy. this is very similar to what learning process?

This is very similar to the learning process that is referred to as classical conditioning.

Explanation:

In the process of classical conditioning, a particular action or a stimulus is associated with a very specific response. In Juanita's case, the role of the stimulus is played by the needle. On encountering a needle, Juanita's brain spontaneously responds to the stimulus and releases a hormone called epinephrine which causes Juanita to develop a sudden feeling of fear, and hence, the dizziness.