Sunday, April 17, 2011


I have been reading the Tell-Tale Brain by V.S. Ramachandran. The experience is like having someone open up my skull and stir a spoon through my previous notions of what it means to be me, to be a human. I think the introduction, A Brief Tour of Your Brain, should be required reading for all psychiatric patients and their families. The knowledge it contains could help eliminate a lot of the guilt and self castigation that accompanies diagnoses of “mental illness”.

As always with science, we must say that what we “know” is based on current evidence. Our ideas will change as we discover more. However, if our current observations hold true, the impact will be mind blowing (pun intended). Philosophy, art and religion will have a lot of catching up to do. Many of our most cherished concepts of things like mind, soul, God and our moral compass will be changed forever. Unless, of course, we ignore science if favor of things like “creationism”.

For example, several regions of the brain appear to be critical to the “human” view of who we are and how we relate to the world. Damage to these areas results in the loss of what it means to be human, at least in any real sense of the word. Without these functions our external bodies might appear the same but our thoughts, behavior and culture would not exist.

Here are a few of the areas most critical to being what is typically defined as “human”. Quotations are from Ramachandran.

WERNICKE'S AREA (upper left temporal lobe) – A uniquely human area (seven times larger than a chimp) provides comprehension of meaning and semantic aspects of language. Damage can result in the loss of ability to process language – no Wernicke's area, no Shakespeare.

PARIETAL LOBES – The left uses sensory input (including muscles and touch) to provide “multimedia” sense of corporeal self. The right provides a “mental model of the spatial layout of the outside world: your immediate environs, plus the location (but not identity) of objects, hazards and people within it”. Damage to the right lobe can cause the phenomenon of hemispatial neglect (loss of awareness of what occurs in the left field of vision) or somatoparaphrenia (belief that left arm belongs to someone else). If you zap the right parietal lobe with an electrode you will have an “out of body” experience.

INFERIOR PARIETAL LOBES (IPL) – Is much larger in humans than any other species and is divided into two regions (angular gyrus and supramarginal gyrus). The left angular gyrus provides functions “such as arithmetic, abstraction, and aspects of language such as word finding and metaphor”. The left supramarginal gyrus provides “images of intended skill actions (e.g. sewing, hammering a nail, waving goodbye) and executes them”. Damage to left IPL eliminate abstract skills like reading, writing, arithmetic, etc. and hinders ability to complete skilled movement. No IPL means no Kobe Bryant and no extravagant metaphors for sports writers to use in describing his talent. Damage here may even mean the end of “free will” - the ability to imagine and execute complex actions.

PREFRONTAL CORTEX – Often called the “seat of humanity”. Can sustain massive damage with no obvious signs of neurological or cognitive deficits, but can cause major personality changes including withdrawal from social world and marked reluctance to do anything at all. This is sometimes called pseudodepression because it looks a bit like depression but is not accompanied by bleakness and chronic negative thoughts. In fact, the person will seem euphoric. Damage also results in loss of: interest in his own future; moral compunctions – may laugh at a funeral or urinate in public; ambition; empathy; dignity as a human being. No prefrontal cortex means no society or culture – at least as we humans describe it.

So what? What does this mean for me? How can I use this information?

First, I can let go of a lot of guilt. I am not ready to completely let go of the idea of free will and my personal accountability, but I can accept that I have a lot less control over my actions than I once thought. Many of the mistakes I have made are not my “fault” anymore than a friend of mine is at fault for the fact that cerebral palsy has robbed him of the ability to control his arms and legs. This information lets me directly refute the thoughts in my head that tell me that I am a “bad” person for making mistakes. With work I can gain some control over my emotions and behavior, but I will never be “fully” in charge. No one has complete control of their thoughts and behavior, and it doesn't appear they ever will. Knowing this gives me evidence that I am not broken. I am human.

Second, I can have a more solid foundation of compassion for the failings of others. When I look at someone who was traumatized or injured at an early age I can better understand and accept their "character defects". I can see that I struggle to grow emotionally, that another of my friends struggles at least in part (perhaps in a very large part) to malfunctions in the Prefrontal Cortex. I can see peoples problems with social awareness and “humanness” the same way I see problems with motor control of a person's arms and legs.

Reducing my sense of guilt and increasing my compassion for others are things that I have heard before – mostly couched in “spiritual” or religious terms. Knowing they are linked to something tangible in my brain makes them more real.

Others may choose to dismiss the scientific study of the brain and body as reductionist nonsense. I do not. To use a metaphors straight from the Weirnecke's Region and IPL of my brain, neuroscience has been a greater source of freedom and “salvation” for my “soul” than literature, philosophy and art combined. To me, science does not reduce or diminish my love of life's beauty any more than knowing that sunlight comes from a ball of gas diminishes my ability to enjoy its warmth on my skin.

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