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Dopamine Levels and Products of the Brain's picture

A quote from Emily Dickinson’s poem reads that “the Brain is wider than the sky”, “deeper than the sea”, and “is just the weight of God” (3). She infers in the poem that what all humans feel, see, smell, taste, hear and think are fabrications of the organ, most familiarly known as the brain. The distinguishing between what really exists and what does not exist are difficult to differentiate since all processes of thought are regulated by the brain. In order to answer those questions, research needs to be done so that there is access to a higher level of thought regulation than the human brain. With this higher level of processing information, much more information of how the brain works can be discovered. However, regardless the question of what exists versus what does not, one thing that is definite is that the human brain and the nervous system is the location where all thoughts and feelings are created. People still debate on whether or not there is a spirit or soul that controls feelings, however, these concepts of spirituality are also results of processes in the nervous system. As time passes in everyday science, scientists are starting to discover more answers to the processes that happen in this organ. Although human thought processes and actions seem to be extremely complicated, there is evidence that shows that it is merely a combination of different chemical hormone levels in the nervous system. However, due to the myriad of cells and types of cells along with the variety of combinations that are possible, there are so many combinations that are yet to be determined.

A specific example for human thoughts and actions being chemically regulated is the relationship between dopamine levels leading to either Schizophrenia or Parkinson’s Disease. A journal entrée was released in the website of the National Center for Biotechnology Information discussing the effects of dopamine levels in the body, which correlated to two gradual ends of the dopamine-level spectrum, either Parkinson’s Disease or Schizophrenia (1,2). Parkinson’s Disease is caused due to deprived dopamine levels in the human body (6,7) while Schizophrenia is due to too much dopamine (5). The treatments to each diagnosis is opposite of each other; Parkinson’s Disease patients supplement their bodies with dopamine while Schizophrenia patients inhibit the increase of dopamine levels (6,7). However, excess levels of treatment to each symptom may be the cause of the other disease ( ). This shows that even with a single hormone like dopamine, is able to control the different actions and feelings of the human body.

Dopamine is a neurotransmitter in the brain that is created in the substantia nigra of the basal ganglia. This neurotransmitter plays an essential role in muscle control in the human body and is also a main contributor to the pleasure pathway for human emotions (4,8). It is possible for dopamine levels to deteriorate, especially when there is deterioration of brain cells in the substantia nigra, causing muscle stiffness, slow movement, instability and even signs of depression. Thus, the deterioration of dopamine producing cells cause the lack of dopamine, which concludes to the symptoms of Parkinson’s disease (7 ).

In order to treat this disease, doctors treat their patients with various dopamine enhancers or dopamine facilitating supplements (acetylcholine) so that their levels in the body can increase. However, excessive amounts of dopamine through the treatment of Parkinson’s disease has shown potential of shifting the dopamine gradient, causing the human body to have too much dopamine. This can lead to mental deterioration, dementia and hallucinations; symptoms of Schizophrenia (5,9 ).

Schizophrenia is mainly known to be a mental disorder due to neurodevelopmental abnormalities (possibilities lie in genetic make up as well as pregnancy errors, exposure to drugs), which lead onto neurodegeneration, brain dysfunction and other symptoms of schizophrenia (9). Stress causes dopamine levels to rise, which is also a suspecting cause of schizophrenia. In order to prevent that, patients are given dopamine suppressors and degraders so that the symptoms can mitigate. But excess amounts of suppressors can once again shift the balance so that the body is lacking dopamine, thus, resulting to symptoms of Parkinson’s disease.

As seen above, with the difference of balance and hormone levels of only one chemical in the human nervous system, various different results can show through a spectrum of brain dysfunctions, ranging from Parkinson’s disease to Schizophrenia. If simply one area or input/output box, like the Substantia Nigra, can cause such various symptoms according to the variability of how the human body can work, then the brain, which is a construction of various areas and infinite number of input/output boxes, is capable of executing an insurmountable number of emotions, actions and feelings. Through only the simple levels of dopamine, the human brain can have many possibilities of output, thus, all brain and body control is regulated by chemical balance of the nervous system. Emily Dickinson’s suggestion about all actions, feelings and senses being fabrications of the brain (suggestion made two hundred years ago) are still emerging and being approved through contemporary science, today.


Works Cited

1. Birtwistle, J, and D Baldwin. " Role of dopamine in schizophrenia and Parkinson's disease" National Center of Biotechnology Information. Department of Psychiatry, University of Southampton, Royal South Hants Hospital. 23 Feb. 2008 <>. 

2. Broadfoot, Marla V. "Dopamine Imbalances Cause Sleep Disorders in Animal Models of Parkinson's Disease and Schizophrenia." EurekAlert. 10 Oct. 2006. Duke University Medical Center. 23 Feb. 2008 <>. 

3. Dickinson, Emily. "Neurobiology and Behavior." Serendip. Bryn Mawr College. 23 Feb. 2008 </bb/neuro/neuro07/index.html#starting>. 

4. "Dopamine Definition." Medicinenet.Com. 23 Feb. 2008 <>. 

5. Falloon, Ian R., Robert R. Kydd, John H. Coverdale,  and Tannis M. Laidlaw. "Early Detection and Intervention for Initial Episodes of Schizophrenia." National Institute of Mental Health. 1996. National Institute of Mental Health. 23 Feb. 2008 <>. 

6. Kaldis, Teresa. "Parkinson's Disease." Disaboom.Com. 23 Feb. 2008 <>. 

7. Kantor, Daniel. "Substantia Nigra and Parkinson's Disease." Medline Plus. 16 May 2006. Comprehensive MS Center, Neuroscience Institute, University of Florida Health Science Center, Jacksonville, FL. 23 Feb. 2008 <>. 

8. McDougal, David, Dave Van Lieshout,  and John Harting. "Substantia Nigra." University of Wisconsin, Madison, Medical School. University of Wisconsin, Madison, Medical School. 23 Feb. 2008 <>. 

9. "Schizophrenia Cause and Prevention." Schizophrenia.Com. 23 Feb. 2008 <>. 




Paul Grobstein's picture

Dopamine the key?

Its an interesting pattern, that high levels of dopamine are associated with schizophrenia, and low levels with Parkinsonism. But if, as you say, the brain is "a construction of various areas", there must be much more than just dopamine variation involved in both schizophrenia and Parkinsonism. And what about the possibility that differences in dopamine are only apparent because that's what investigators happened to be looking for, and that those variations are actually secondary to some other changes? In this case the observed pattern might be much less significant.