Some might say that brain researcher Jill Bolte Taylor got the research opportunity of a lifetime; in 1996, she experienced a stroke that enabled her to "research" the shutdown of the brain's left hemisphere from the inside out. A hemorrhage in that hemisphere rendered her unable to walk, talk, read or write. In her 2008 TED talk, she became an "infant in a woman's body"; however, she had full access to the functioning of her right hemisphere, which opened her up to a way of being in the world she hadn't known was possible.
Right vs. Left?
Put in computer terms, Jill found that the right hemisphere of the brain is like a parallel processor, able to process lots of information simultaneously; the left hemisphere functions like a serial processor, only able to process one piece of information at a time. In other words, the left hemisphere is linear, and the right hemisphere is totally outside of linear time.
The Left Hemisphere
The left hemisphere thinks methodically and is all about the past and future, not the now. It filters, categorizes, sorts and organizes the "collage" of information brought in by the right hemisphere, grabbing details and organizing them based upon our experiences of the past. It then projects possible futures to "help" with decision-making going forward; however, an over-active left brain can cause stress, worry and anxiety about things that may or may not happen.
The left brain thinks in language and is responsible for our "brain chatter" or "monkey mind." It is a calculating intelligence, the voice that causes us to say "I am" and to feel/seem separate from others and from the flow of the Universe. Without the left hemisphere, one is left with a sense of "Oneness" as experienced by the right hemisphere; however, we cannot do much in the material world.
The Right Hemisphere
The right hemisphere pulls in the data around us in a non-linear fashion. The right brain is all about the present moment, the "now." It learns through pictures and kinesthetic feelings/experiences. Information as energy streams in through the senses and is registered in a big "collage." The right brain allows us to feel a connection with the world around us and with other people -- no boundaries, no separation. There is Oneness consciousness here, and in this moment Jill says we are all "perfect, whole and beautiful."
When Jill's left brain went "offline," she shifted to a "witness" perspective of herself. She could no longer define where her "boundaries" began and ended; the atoms of her body merged with the atoms of the wall and the other things around her. She no longer experienced herself as separate. The left hemisphere brain chatter went totally silent; she was "shocked" to have a silent mind, and was captivated by the beautiful energy all around her. The stress of life, the mind chatter and the emotional baggage of her past were all "gone" -- and she felt euphoric.
However, without a left brain, she saw printed things as "pixels," no longer understood letters and numbers, lost the capacity for language and could not discern her place in space. She felt "huge" energetically, not constrained to her physical body, to the point where she didn't think she could fit the "enormousness" of herself back into her body. (Interestingly, this is also often reported by those who have near-death experiences.)
Despite the limitations, Jill was experiencing euphoria -- Nirvana.
It took Jill eight years to completely recover the use of her left brain and function in the world again. However, her stroke left her with many insights. She now envisions a world filled with beautiful, peaceful, compassionate, loving people -- where anyone can "step to the right" of their left hemisphere anytime and experience this beautiful euphoria, this connectedness and Oneness. She dreams that someday this will be possible for all humans, without the need to have a stroke. It seems that this is what Enlightenment in many spiritual traditions aims to accomplish as well.
Who/What Are We?
According to Jill, at our very best as humans we can be "the life-force power of the Universe" -- with "manual dexterity." We have two minds -- and we can bring out the best of both of them. The left hemisphere causes a sense of separation, but it allows us to function and have volition in the world. The right hemisphere is our "deep inner peace circuitry," and if we can access this perspective more of the time, a much more loving and peaceful world is possible.