Mind does not exist in our body.

From the Master Key System:

28 . The Universal Mind is static or potential energy; it simply is; it can manifest only through the individual, and the individual can manifest only through the Universal. They are one.

42 . We live in a fathomless sea of plastic mind substance. This substance is ever alive and active. It is sensitive to the highest degree. It takes form according to the mental demand. Thought forms the mold or matrix from which the substance expresses.

Mind is consciousness and they are all around us, it is how we manage to connect with another person even though we may have no real physical contact with each other.

The body is the projection of your spiritual self into the physical realm. Your mind takes shape and form in the body, your entire body.

The mind-body duality is our way of describing the transition between this world and the next. But it is not necessary; it is just another separation, another mental projection.

It is said that a silver cord connects our physical body to our astral one. But that, too, is a mental projection. You can simulate out of body experiences with Ketamine, a dissociative anesthetic. You can simulate religious experiences with peyote. These experiences are indistinguishable from the "real thing."

Of the parts of the body that are most associated with mind, the brain is always described as the organ which specializes in mental function. But that should come as no surprise; all of the other organs in our body are specialized in their function also.

This might surprise you, but humans have a second layer of intelligence in the form of a complex neural network that resides in the abdomen. This is where "gut feelings" come from.

I believe your mind is not located in the body. However, it is probably accessed through the brain.

First of all it is important to understand that the human brain and the mind are not the same things. Both the mind and mind power are purely a non physical aspect of you capable only of processing pure consciousness (unseen or spiritual), while the brain is the physical tool that the mind utilizes to process the thoughts derived from consciousness, enabling the manifestation or the physical appearance of the thing thought of (the ideal) in the physical world.

http://www.abundance-and-happiness.com/mind-power.html

Your brain is in your skull while the mind is not.

The mind is in every cell of your body. What we call the mind is really an energy. It is . . . thought. And thought is an energy, not an object. The brain is an object. It is a physical, biochemical mechanism—the largest, most sophisticated, but not the only—mechanism in the human body, with which the body translates, or converts, the energy which is your thought into physical impulses.

Your brain is a transformer. So is your whole body. You have little transformers in every cell. Biochemists have often remarked at how individual cells—blood cells, for instance—seem to have their own intelligence. They do, in fact.

And there are more cells in your brain than anywhere else, so it seems mind is there. Yet that is just the main processing center, not the only one.

Source - Conversations With God - Book 3