The heart is not the same as the emotions. Think of a large sponge in the cavern of your soul, absorbing the echoes from the heart as well as from the mind; the good absorbed with the bad. When the emotions are in a situation that reminds it of another situation it breathes out the stored feelings and stimulates the mind and body to prepare for the anticipated response. The heart is pure at its source as it is connected to the heart of Christ. When Christmas comes around your sponge breathes out what it anticipates "Christmas" to be. It is not the truth and sometimes not even a fact but a "justified" feeling from the past. The Holy Spirit of God does not manipulate His believers by using the emotions. He fully uses the heart, that is His primary point of contact with us believers.
Emotions can be programed with a strong mind and repetition. I used to throw newspapers. I hated picking up the newspapers from the warehouse. It was full of smoke from cigarettes and some very rough people. They seemed to growl at me for some reason. Well, one day I got tired of not liking it and decided to use my mind to overwhelm my emotions. I lied to myself by saying "I love to pick up the newspapers." Nothing changed but my attitude. Wow. I am dumber than I thought. I began to look forward to picking up the papers. I started talking to different people and found out they were not as rough as I thought nor were they the ones that were growling. While most of life contains deep and powerful grief that must be experienced, so much of life is based upon our ability for our mind to enslave our feelings and our mind's submission to the heart.