The brain/mind connection
The human brain is a 1500-gram semisolid gel of infinite complexity. An electrical and chemical laboratory that uses our senses as specially designed microphones to pick up sensations and storing them as knowledge in the brain cells.
When different sensations come into the mind at the same time, the brain groups them together as if they were related. This is called the law of association. It takes seemingly unrelated sensations, unites them and creates something new that wasn't even sensed. The essence of creativity is uniting two or more previously unrelated things into a workable relationship, thus making it into something new. This association of seemingly unrelated things is knowledge. You stick your finger into a candle flame and it's painful. The mind associates fire with pain and you know that if you stick your finger in the flame it's going to be painful. That knowledge is the basic substance and building material of our minds. If we were to explain what the mind is made up of, we would have to say that it is made up of knowledge structured in the form of human language. Animals also have knowledge, but it's structured in another way. They don't have human language so they don't talk about it in the same way as we do, but they communicate it in other ways as in certain sounds and behaviors.
The left and right brain hemisphere split
Our brain is split into the left hemisphere and the right hemisphere. Each hemisphere dominates specific sets of functions. This split is called the right-sided creative mind and the left-sided rational mind. This corresponds to the relationship between the brain and the mind. The brain stores direct sense experience and creates the concrete rational mind and the law of association associates those experiences creating the abstract creative mind. Models have been created that sort people into two groups depending on which hemisphere is dominant, for example. the artistic emotional person and the scientific logical person. But this left brain right brain split is a little misleading. It's not a complete physical split of functions because the left side can learn to do things usually located in the right brain and vice versa.
Both the concrete and abstract mind share a common characteristic, they are mostly unconscious. But there is a third element in this equation which we call the whole hemisphere.
The Left Hemisphere
The left hemisphere or concrete mind structures and stores information in a linear, precise and exact manner. It's calculating, logical, rational, digital, mathematical and auditory. It deals with things that are empirical and can be measured, weighed and verified objectively. Things that are physical and material such as space, atoms, matter, electrons, molecules, brains and neurons. It relies on facts, figures, measurements, concrete knowledge, detailed explanations, rational thought, memory, reason, logic, direct sense experience which is empirical, measurable and verifiable. Science is the product of left hemisphere function.
The concrete mind uses deduction to arrive at conclusions. It goes from the general to the specific, from cause to effect. It states: "All men are mortal. Socrates is a man. Therefore, Socrates is mortal." It assumes and preconceives. It sees the effects of things and arrives at the fact. The concrete mind allows a belief to create an experience. It goes from fact to explanation, from belief to explanation. It draws from, in reasoning, to attain or arrive at, as a truth, opinion, or proposition, from premises, to infer from what precedes, to conclude. It takes away, separates, or removes, in numbering, estimating, or calculating, to subtract, as from the sum of two numbers. It reasons from a known principle to an unknown, from premise to a logical conclusion. It begins with general truth, and seeks to connect it with some individual case by means of a middle term or class of both objects known to be equally connected with both. Thus it deduces the specific from the general, attributing to the former the distinctive qualities of the latter. It says 2+2=4. When it sees something it doesn't judge or estimate it is neutral and unattached. It is "a priori" and based on assumption-as-bottom-line, a belief that doesn't depend on experience for validation, a "general principles" of the two-plus-two-equals-four, no plant can get up and walk.
The Right Hemisphere
The right hemisphere or abstract mind structures and stores information in a circular, creative and vague manner. Its dreamlike, abstract, poetic, imaginative, mystical, emotional, metaphoric, musical and visual. Its content is changeable, variable and subject to interpretation. It deals with mystical things, time, understanding, meaning, abstract knowledge, miracles, faith, healing and ideals. It relies on loyalty, honor, faith, belief and emotion, stories, metaphors, analogies, poetry, idealism and images. Religion is the product of right hemisphere function.
The right mind induces. It goes from specific to general, from effect to cause. It sees a fact and then interprets it and says what it means. It's unassuming. It filters experience through an existing model. It records instances, monitors behavior and counts noses. It goes from explanation to fact that leads on to some action, condition or belief, as by persuasion or argument. It produces, brings on and causes by induction such as inducing a fever from extreme fatigue. The abstract mind uses induction to come to conclusions. It reaches a conclusion by inference from particular facts. It brings about an electric or magnetic effect in a body by exposing it to the influence of variation of a field of force. It installs and initiates. It begins, leads or brings into. It uses the process of reasoning or drawing a conclusion from particular facts or individual cases and the conclusion reached by such reasoning. It observes a sufficient number of individual facts, and on the ground of analogy extends what is true of them to others of the same class, thus arriving at general principles or laws. It says 4=2+2 or 3+1 or 4+0 or 6-2 or 4x1 etc. It is "a posteriori" and derives knowledge from observation, the this-box-is-red; everybody's sentimental on Valentines Day variety. It gets to it after looking around for itself.
So we can safely assume that the left mind is closely associated with the physical world and that concentration controls the functions of the left mind. And we can also safely assume that the right mind is closely associated with the spiritual world and that perception controls the functions of the right mind. Now we need to find out what controls the functions of the spiritual world.
The Whole Hemisphere
The whole hemisphere or balanced mind is clear, simple, lucid, clean, inspirational, illuminating and ecstatic. It sees both sides of an event, the direct one and the interpreted one. It contains the feminine and masculine, the negative and the positive minds and is therefore neutral. Yoga is the product of balanced mental function. It deals with awareness, peace, love, harmony, illumination, silence, grace and beauty. It relies on discipline, meditation, daily practice and selflessness.
The balanced mind uses intuition to come to conclusions. It integrates and organizes various traits or tendencies into one harmonious whole. It integrates and leads to integrity. It synthesizes. It puts two or more things together so as to form a whole. It joins analysis and interpretation. It is a whole made up of parts, or elements put together. It goes from the simple elements of thought into the complex whole, from a principle to its application, car parts into car, organs into human.