Read The Root of Thought Online

Authors: Andrew Koob

The Root of Thought (23 page)

Consciousness and cognition can be severely disrupted by a brain tumor. Although the increase in astrocytes—the pondering imaginative thinking cell in the brain—might be beneficial in the case of healthy cells, after the cells turn into little gremlins, they do not function as a cohesive calcium wave unit. They also push aside the neural roads they need to use to transfer information long distances for action, destroying and mashing everything in their wake. If a brain tumor could increase our intelligence through the increase in astrocytes, everyone with a tumor would be walking around like John Travolta’s character in the movie
Phenomenon
.

Cognitive problems in patients with brain tumors differ based on where their tumors reside. A tumor can occur almost anywhere in the brain. An obvious place is the walls of the lateral ventricles where dividing astrocytes can morph and invade the cortex. Tumors in this area can strain the optic nerve and cause visual problems, including blindness. Headaches and seizures are also common problems that people with tumors can experience.

To determine the location of a tumor, doctors use imaging equipment to take pictures to pinpoint the location before performing the tricky task of removing it from the slop of the brain, the teeming mass that is responsible for their patients’ thoughts and dreams. Anything can happen afterwards—personality changes, a vegetative state, or death. The most dreaded area is called Broca’s area, which is the left temporal cortex where the speech area resides. Tumors in the temporal cortex look a like a fist sitting in the side of the brain. For humans, speech is the most important function that we possess. Without speech, we are unable to communicate with other people or intelligently pass information to other people. Damage to this area also disrupts nonverbal communication; a hearing-impaired person who communicates through sign language would be impaired and unable to communicate as well.

The other concern that frightens doctors is if the medulla is under strain. If the tumor is a medullablastoma or the tumor disrupts the medulla—the area that is responsible for breathing and other involuntary functions we need to live—it is difficult to perform surgery. The surgery becomes a life-or-death situation. Sometimes, the tumor can reach out like a spider, almost looking like a giant astrocyte. In this case, it is difficult to remove the malignant cells and the tumor can make a comeback. Some tumors in the base of the brain starting in the area of the substantia nigra are responsible for Parkinson’s Disease and can create a butterfly pattern in the brain, with wings reaching up into each hemisphere.

Doctors publish short case histories when they encounter something interesting or different. One case was the result of a patient who had been diagnosed with Parkinson’s Disease for 14 years. As his symptoms began to increase, he saw little green and orange monkeys jumping across the room. The patient then reported seeing men in green uniforms marching around, on top of dreams that he was fighting
Braveheart
-type bloody battles and being tortured by aliens.

After an MRI was taken, it showed that the poor patient didn’t have Parkinson’s Disease at all, but a massive butterfly tumor covering much of his brain (see
Figure 14.1
). Because it is known that Parkinson’s Disease can lead to some hallucinations in patients, the doctors had difficultly pinpointing the problem because the patient’s hallucinations were much more aggressive than someone with the disease. For a time, they had diagnosed him as being psychotic.

FIGURE 14.1 MRI of butterfly tumor spreading in the brain of a patient originally diagnosed with Parkinson’s Disease.

 

Reprinted from
The Lancet
, Vol. 370, Issue 9598, Guptha, S.H., Han, T., Arafat, Q., and Deyo, O. “Orange and Green Monkeys Jumping Around the Room,” p. 1588, Copyright (2007), with permission from Elsevier.

One of the most curious cases occurred in a housewife in Innsbruck, Austria. She had a tumor in her left parietal cortex. After removal, researchers noticed she had difficulty calculating numbers. She could memorize a math problem, but couldn’t understand how to multiply or divide. This is the same area in which Einstein had excess glia. However, in the woman’s case, she didn’t become a math genius; she suffered the inability to think on a higher mathematical level. Sadly, researchers do not know if she had deficits before the surgery. The problem in mathematical conceptualization instead is most definitely the result of taking out an area of the brain responsible.

In another patient, the tumor caused him to experience sensations of déjàvu and of watching a bright movie, with images moving in front of a bright light, like dancing figures before a hatch opening in an illuminated spaceship at night. After surgery, the patient experienced the overwhelming sensation of someone nearby looming over his shoulder. When
the patient was lying in bed, it felt like someone was in bed with him (not such a bad thing, if it is Natalie Portman or Christina Ricci, but very troubling if it is someone who isn’t there). This sensation can best be described as something akin to when you are working late at night and it feels like there is a ghost in the room. The tumor was in the area near the amygdala in the base of the brain. People have claimed this feeling when receiving an electrical stimulus to the amygdala, the area responsible for emotional modulation.

Other strange cognitive problems that arise warp visual images. Patients experience tracking of images like they have taken hallucinogens, but the images still leave an after-print of an object immediately in the vicinity, similar to a bird flying through the air that passes by and seems to leave a cartoon afterimage.

In another case, a patient with a tumor in the left temporal lobe near Broca’s area, the valuable area for speech, couldn’t remember names and dates. He had absolutely no problem cognitively in any other aspect of his thinking. He just simply couldn’t remember his telephone number, address, and dates—random important numbers that had been etched in his brain.

In another wild sensation with astrocytomas in the cortex, one of the phenomena occurs with tumors in the right cortex. The result is the feeling of multiple selves in the room with you, called polyopic heautoscopy. Patients think more of them are walking around the room, as though they have been cloned. There might be five of them, as if someone had thrown a rock against a mirror and the other bodies exploded out of it and were just hanging around. The experience isn’t like multiple separate personalities, but actually the belief that several people, all you, are existing simultaneously in the same space and time as you.

All these cases point to possible evidence for astrocytes functioning in warped behavior as the tumor grows. At a certain point, they become so destructive that they eliminate functioning in the area they have invaded. However, when it is initially beginning, astrocytes can give the feeling of multiple selves or déjàvu, possible evidence for astrocytes as the seat of thinking and information in the brain. In the problem of a tumor in Broca’s area that destroys a person’s communication ability, it would be interesting to know what exactly the patient experienced. However, they would be unable to perform that unique human trait of complex verbal communication. In mice and rats, naturally occurring glioblastomas do not seem to
occur; astrocytomas are the most prominent tumors. In dogs, tumors similar to those found in humans form as they age. In dogs, astrocytomas are the most prominent, oligodendrogliomas the second most prominent, and glioblastomas, the most common in humans, are the third most common.

Incidence of brain tumors has also been reported in horses, cows, sheep, goats, and pigs. The occurrences in animals are extremely low; however, these animals do not usually live out their entire lifespans and might not have the opportunity to develop brain cancer. The prevalence of tumors in dogs was also much higher than what was seen in cats. Boxers, Boston terriers, and bulldogs were the breeds with the highest incidence of brain tumor development, indicating a genetic factor at work at least in dogs.

In humans, it is telling that tumors comprised of astrocytes occur separate from degenerative diseases of the brain. Doctors will not see them both in the brain at the same time except in cases of multiple sclerosis. Multiple sclerosis is unique compared to other diseases of the brain. In multiple sclerosis, it seems that the immune system from outside the brain attacks the myelin on neuronal axons. Astrocytomas and glioblastomas can occur in these patients; it is possible multiple sclerosis triggers the astrocyte response of growth. This growth might be a glitch in the astrocyte’s eager response to save its degenerating neuronal roads by regenerating itself, which is like the massive effort to repair a bridge after it collapses.

It is possible that astrocytes have the capability to go one direction or the other, either as rabid dividing gremlins, causing cancer or dying off without replacement and causing an astrocytic wasteland, which results in degenerative disease. The normal turnover of astrocytes in the brain is a simple and natural process (see
Figure 14.2
). Like cells in the lung, the astrocytes deal with our environment by monitoring the blood flow to the brain and processing information brought in by the neurons from the senses.

FIGURE 14.2 The astrocyte continuum curve—a balance of astrocyte death and growth—is required for a normal, healthy human brain.

 

When the trigger sends astrocytes to insanely divide, they become invasive and concerned with one thing: taking all the energy in the vicinity to facilitate more growth. They push on to other areas of the brain, which causes the cells to rupture and die. That’s the drawback of living on the planet earth where everything is intertwined with growth. Plants grow and are eaten by animals that grow and are eaten by animals that grow and die and are used by plants that grow. In growth, sometimes there’s too much and sometimes there’s too little.

As we work our brains to create more beneficial astrocytes to counteract those that are lost as we age and to keep our mind young, sometimes the brain short-circuits and cells become cancerous. However, neurons rarely turn cancerous. Neurons are simply the glue that enable astrocyte communication. Astrocytes constantly change, grow, and move. Subordinate neurons exist because of astrocytes. Astrocytes contain our thoughts and reasons for existence. The motivation of astrocytes is our motivation. Our bodies are vessels to support their existence; the body has evolved to surround these cells that are responsible for growth and have existed since the dawn of life.

References
 

Brugger, P., O. Blanke, M. Regard, D.T. Bradford, and T. Landis. “Polyopic Heautoscopy: Case Report and Review of the Literature.”
Cortex
, 42: 666–674, 2006.

Delazer, M. and T. Benke. “Arithmetic Facts Without Meaning.”
Cortex
, 33: 697–710, 1997.

Folkman, J. “Angiogenesis in Cancer, Vascular, Rheumatoid and Other Disease.”
Nature Medicine
, 1: 27–31, 1995.

Gupta, S.H., T. Han, Q. Arafat, and O. Deyo. “Orange and Green Monkeys Jumping Around the Room.”
Lancet
, 370: 1588, 2007.

Hegi, M.E., A. Diserens, T. Gorlia, M. Hamou, N. de Tribolet, M. Weller, J.M. Kros, J.A. Hainfellner, W. Mason, L. Mariani, J.E.C. Bromberg, P. Hau, R.O. Mirimanoff, J.G. Cairncross, R.C. Janzer, and R. Stupp. “MGMT Gene Silencing and Benefit from Temozolomide in Glioblastoma.”
New England Journal of Medicine
, 352: 997–1003, 2005.

Kleihues, P., P.C. Burger, and B.W. Scheithauer.
Histological Typing of Tumors of the Central Nervous System
. World Health Organization International Classification of Tumors. Berlin: Springer, 1993.

Nakasu, S., T. Fukami, K. Baba, and M. Matsuda. “Immunohistochemical Study for O6-Methylguanine-DNA Methyltransferase in the Non-neoplastic and Neoplastic Components of Gliomas.”
Journal of Neurooncology
, 70: 333–340, 2004.

Ohgaki, H. and P. Kleihues. “Epidemiology and Etiology of Gliomas.”
Acta Neuropathologica
, 109: 93–108, 2005.

Other books

The Mike Hammer Collection by SPILLANE, MICKEY
The Arena: The Awakening (1) by James Robert Scott
Riverrun by Andrews, Felicia
Freckle Juice by Blume, Judy
The March Hare Murders by Elizabeth Ferrars
Beloved by Antoinette Stockenberg