Course:EOSC311/2022/How Geological Factors Impact the Development of Schizophrenia
Introduction
In psychology it is important to consider all the factors that could lead to the development of disorders. Geological resources have been found to play a role in variation within psychological processes across multiple areas. For instance, Schizophrenia, a neurodegenerative disorder which is categorized by the loss of touch with reality and the presence of psychosis, has been linked to various genetic and environmental risk factors. These environmental factors can be explored in depth by examining the effects of common geochemicals, such as Copper and Lead, which research has found to be related to the development of the symptoms that are commonly associated with schizophrenia. By examining the connection between these elements in geology and schizophrenia, a clearer etiology can be developed which may result in more treatment options being pursued.
Schizophrenia
Schizophrenia is a chronic brain disorder that affects the way people think, their expression of emotions, and how they perceive reality. Schizophrenia involves a psychosis, which is a set of symptoms characterized by a disruption in the way that the brain processes information, leading to people losing touch with reality and finding it difficult to differentiate whether something is real or not. People with schizophrenia often have problems doing well in society, at work, at school, and in relationships. They might feel frightened and withdrawn, and could appear to have lost touch with reality. People with schizophrenia often feel frightened and withdrawn from society. In men, the symptoms of schizophrenia start in the late teens or early to mid-20s. In women, symptoms tend to begin in the late 20s. It's uncommon for children and people over the age of 45 to be diagnosed with schizophrenia. [1]
The Symptoms of schizophrenia are differentiated into different categories [2]:
Positive Symptoms:
These refers to the addition of abnormal thoughts that aren’t based in reality, which can include:
Hallucinations: These involve experiencing sensations that do not exists. For instance hearing voices or seeing things that are not real
Delusions: These are false beliefs that are not based in reality.
Catatonia: A lack of movement and communication
Disorganized Symptoms:
Confused and disorganized thinking and speech, trouble with logical thinking, being unable to make decisions and abnormal movements.
Cognitive symptoms:
These include difficulty with understanding information and using it to make decisions due to poor executive function. Problems with paying attention and difficulties using information immediately after learning it due to poor working memory.
Negative Symptoms:
These refer to the absence of normal behaviors which include: a lack of emotion, a lack of energy, withdrawal from social activities, a lack of motivation and pleasure and poor personal hygiene.
How severe the symptoms of schizophrenia are can vary between people. Some people may have many psychotic episodes during a lifetime but lead relatively normal lives in between. Others may have more trouble functioning over time, with little improvement in between.[2] There is currently no cure for schizophrenia, however a variety of antipsychotic medications are used to improve the symptoms, reduce their severity and to minimize the chances of a relapse.[1]
The Connection between Geological Elements and Schizophrenia
The exact cause of schizophrenia isn’t known. However researchers have uncovered a number of genetic and environmental risk factors that could increase the likelihood of developing the disease. In terms of environmental causes, over exposure to certain element may trigger schizophrenia in people whose genes make them more likely to get the disorder. It had been found that Copper and Lead, common elements that are found in many soils and ground water, may influence the incidence of developing schizophrenia. I chose to look further into this connection to understand how geochemical factors can be part of the etiology of schizophrenia and the treatment options that can be developed by investigating these factors.
Copper:
It has been suggested that high levels of copper have been linked to the development of schizophrenia. Copper is an element that is present in rock, soil, ground water, and sediment. It is mainly found in porphyry deposits, which occur at subduction zones.[3] These deposits were molten rock that cooled and solidified in the Earth's crust. As they cooled, some large crystals grew, and more rapid cooling resulted in the formation of smaller crystals. [3] At first, copper was spread throughout the mass of molten rock in low concentrations. As the magma cooled and crystals started forming, the amount of melt became smaller.[3] The copper which remained in the melt, becoming more concentrated. When the rock was almost completely solid, it contracted and the remaining copper-rich fluid was squeezed into the cracks within the rock, where it solidified.[3] Over millions of years, the rocks covering these deposits eroded and the deposits appeared at the surface. The high temperatures of volcanic magma creates hydrothermal veins, allowing some of the heat to escape near the upper layers of the Earth’s crust. [4]This copper is often found in sedimentary layer, where sand and mud are compressed until they form a layer of sedimentary rock on the surface of the earth because copper ore gets trapped in oxidized zones within these types of rocks [4].
The average dietary intake of copper is about 5 mg daily [5]. Most of that copper is excreted, but about 50% passes through the liver and enters the circulatory system via ceruloplasmin, a blood protein which binds about 95% of the copper in blood serum.[5] Evidence for the Copper Hypothesis of Schizophrenia come from repeated observations of high copper levels and ceruloplasmin in patients with schizophrenia.[6] Heilmeyer measured the blood serum copper of a group of patients with schizophrenics and found that 86% had "elevated" copper in their blood.[5] It has also been found that when patients that are undergoing dialysis accidentally accumulate excess copper ions in their blood they can display symptoms of psychosis causing a loss of touch with reality.[6] Copper chelators are drugs that reduce the toxic level of copper in the body and they have been found to improve the symptoms of schizophrenia patients.[6] Therefore, evidence suggests that exposure to high levels of copper may be linked to the development of the symptoms of schizophrenia.
Lead:
Lead is another geochemical that has been linked to the development of schizophrenic symptoms. Lead is produced mainly from three types of deposits: Sedimentary exhalative, Mississippi Valley type, and Volcanogenic massive sulfide.[7] Sedimentary exhalative are formed when magma is released into a an ocean , which leads to the precipitation of ore-bearing material within sediments on the ocean floor.[7] Mississippi Valley type deposits are characterized by lead concentrations within carbonate sediment rocks[7]. Volcanogenic massive sulfide are Lead accumulations that form on the seafloor due to hydrothermal vent fluid discharge.[7] According to the U.S. Agency for Toxic Substances and Disease Registry, environmental levels of lead have increased substantially over the past three centuries due to human activity, such as the burning of fossil fuels.[7]
Dr Tomas Guilarte from the Department of Environmental Health Sciences at Columbia University found that prenatal lead exposure can lead to an increased rick of schizophrenia later in life as it has an inhibitory effect on the N-methyl-D-aspartate receptor (NMDAR).[8] This receptor is important to brain development, learning, and memory. In his study Dr Guilarte and colleagues looked at mice engineered with a human gene for schizophrenia called DISC1.[8] Half the mice were exposed to a high level of lead and the other half were not, their brains were then examined using MRI. They found that the mice who were exposed to the lead experienced behaviors and structural changes in their brains consistent with schizophrenia.[8] They had lower levels of executive functioning and had larger lateral ventricles, which mirror schizophrenia in humans. [8] Their research in rodents found that exposure to lead reduced the function of the NMDAR.[8] The glutamate hypothesis of schizophrenia suggests that a deficit in the activity of NMDAR can explain the dysfunction of schizophrenia symptoms. [8]
Further research was conducted by Modabbernia et al. who examined the association of metals exposure with schizophrenia.[9] A total of 14 participants were studied - 9 people with schizophrenia and five people as control. The metals which were analyzed were lead, manganese, cadmium, copper, magnesium, and zinc.[9] The results showed a positive correlation between early lead exposure and schizophrenia. Lead levels were higher in schizophrenia compared with controls.[9]
Lin et al. then conducted reaserch in China looking at environmental lead pollution from large lead mines and its impact on children's blood lead levels.[10] They studied 379 children, 15 yearls old and younger, in 7 villages near lead mines and processing plants, as well as a control group of 61 children from another village.[10] They found that lead concentrations in soil and household dust were much higher in polluted villages than in the control village[10]. They also found that children in the polluted area had high blood lead levels in comparison to the control village[10]. They concluded that the lead industry caused substantial environmental pollution that led to high BLLs in children living nearby[10]. This may then increase their risk of developing schizophrenia symptoms than controls who did not live near a large lead mine.
Conclusion
Understanding how geochemicals play a role in the etiology of schizophrenia is important as it highlights the various environmental factors that can contribute to the development of symptoms. By completely examining all the possible causes of the disease, more successful treatment plans can be developed which target these environmental factors. For instance, understanding the link between copper and schizophrenic symptoms has been beneficial in developing antipsychotic medication such as copper chelators, which reduce the amount of copper in a persons blood and helps reduce their symptoms.
Additionally, the implications of understanding Lead's role in inhibiting NMDR can be beneficial in developing treatments for schizophrenia which target the effects of early lead exposure. This research also highlights the importance of staying in an environment where exposure of high levels of lead are low, especially if a person has a genetic predisposition to developing the disease. While there is a genetic component to schizophrenia, as different combinations of genes make people more vulnerable to developing condition, It does not mean that they will always develop it [11] . As shown in the research, living in areas with a lead mine and having a high copper blood level, can be an environmental factor that increases the risk of developing schizophrenia. Therefore, by limiting exposure to high levels of Lead and Copper, individuals who may have the genetic factors that predispose them to developing the disease may be able to prevent its onset.
References
- ↑ 1.0 1.1 Torres, F. (2020, August). What is schizophrenia? Psychiatry.org - What is Schizophrenia? https://psychiatry.org/patients-families/schizophrenia/what-is-schizophrenia#:~:text=Schizophrenia%20is%20a%20chronic%20brain,thinking%20and%20lack%20of%20motivation.
- ↑ 2.0 2.1 WebMD. (n.d.). Schizophrenia: Definition, symptoms, causes, diagnosis, treatment. WebMD. Retrieved from https://www.webmd.com/schizophrenia/mental-health-schizophrenia
- ↑ 3.0 3.1 3.2 3.3 Copper. Copper | Geoscience Australia. (n.d.). https://www.ga.gov.au/education/classroom-resources/minerals-energy/australian-mineral-facts/copper
- ↑ 4.0 4.1 Copper. Earth Sciences Museum. (2018, November 12). https://uwaterloo.ca/earth-sciences-museum/resources/detailed-rocks-and-minerals-articles/copper#:~:text=Copper%20is%20a%20metal%20that,rocks%20are%20called%20copper%20ores.
- ↑ 5.0 5.1 5.2 Bowman, M. B., & Lewis, M. S. (1982). The Copper Hypothesis of schizophrenia: A Review. Neuroscience & Biobehavioral Reviews, 6(3), 321–328. https://doi.org/10.1016/0149-7634(82)90044-6
- ↑ 6.0 6.1 6.2 Persinger, M. A. (1987). Geopsychology and geopsychopathology: Mental processes and disorders associated with geochemical and geophysical factors. Experientia, 43(1), 92–104. https://doi.org/10.1007/bf01940360
- ↑ 7.0 7.1 7.2 7.3 7.4 Uses of lead. geology. (n.d.). Retrieved from https://geology.com/usgs/lead/
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 Guilarte, T. R., Opler, M., & Pletnikov, M. (2012). Is lead exposure in early life an environmental risk factor for schizophrenia? Neurobiological connections and testable hypotheses. NeuroToxicology, 33(3), 560–574. https://doi.org/10.1016/j.neuro.2011.11.008
- ↑ 9.0 9.1 9.2 Agustina, L., & Arminsih Wulandari, R. (2019). Environment as risk factors of schizophrenia: A systematic review. KnE Life Sciences, 4(10), 420. https://doi.org/10.18502/kls.v4i10.3747
- ↑ 10.0 10.1 10.2 10.3 10.4 Lin, S., Wang, X., Yu, I. T., Tang, W., Miao, J., Li, J., Wu, S., & Lin, X. (2011). Environmental lead pollution and elevated blood lead levels among children in a rural area of China. American Journal of Public Health, 101(5), 834–841. https://doi.org/10.2105/ajph.2010.193656
- ↑ NHS. (2019, November 11). Causes - Schizophrenia. NHS choices. https://www.nhs.uk/mental-health/conditions/schizophrenia/causes/#:~:text=Genetics,mean%20you'll%20develop%20schizophrenia.
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