HIV and the Central Nervous System

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One major difficulty regarding the nervous system is Central Nervous System Dysfunction. The Central Nervous System, otherwise known as CNS, is one of two major parts of the human nervous system, which is composed of the brain, spinal chord, and optic nerves. The other major part is the Peripheral Nervous System, which is composed of the neurons that are not found in the Central Nervous System. Nerves are special cells in organisms that give the person the ability to sense and feel things in and around their environment. These nerves also give the person the ability of locomotion. The brain is the center of this marvelous system, which is also where 2/3 of the body’s neurons are located, because it sends and receives chemical and electrical signals throughout the entire body. Unfortunately these neurons die early, which is the cause of CNS dysfunction.

However, there are other ways in which your nervous system does not function properly. This is caused by many reasons. First of all, neurons work in a complicated manner. The brain starts by sending an electrical signal to the first neuron, and then the signal travels from the top to the axon of the neuron, which is like a tail, and gets to the end dendrites, which are pointy finger-like projections that keep the signal going, of the first neuron. Then, since there is a gap between neurons, the electrical signal changes to a chemical signal to cross the gap, and turns back into an electrical signal when it reaches the next neuron. It continues that pattern until the signal reaches its destination, which takes less than a fraction of a second. Chemicals are the main reason why signals get blocked. These chemicals can intercept the chemical excreted by the dendrites and cause the signal to be lost, or it can completely block the electrical signal from turning into a chemical signal.

AIDS Dementia Complex, otherwise known as ADC, is a specific neurocognitive complaint that arises from AIDS. Unlike other dementias, which are easy to treat and recover from, ADC is completely irreversible because it is a disorder that arises from AIDS. Some scientists speculate that this is an opportunistic infection, while others argue that it is actually caused by AIDS directly. This disease works by attacking every single part of your brain, eventually leaving you to die because it reaches a point, in which it attacks the entire CNS, which leaves you immobile. There are a few stages of ADC, raging from mild to severe in health risk. It begins with stage 0, where the patient hasn’t lost any brain tissue. The following stage is 0.5, this is the start of brain tissue removal. At stage 1, patients are diagnosed with minimal brain deterioration. At stage 2, a patient is being disconnected with their body. At stage 3, the person has hit severe brain malfunction, and has completely lost themselves. At stage 4, the patient is left in a vegetative state, leaving them to die. ADC may be the reason why AIDS patients are have poor performances on motor tests and verbal learning.

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Sources:

-Rourke, Sean B., Mark H. Halman, and Chris Bassel. "Neurocognitive Complaints in HIV-Infection and Their Relationship to Depressive Symptoms and Neuropsychological Functioning." Journal of Clinical and Experimental Neuropsychology 21 (1999): 736-749

-Millikin, Colleen P., Sean B. Rourke, Mark H. Halman, and Christopher Power. "Fatigue in HIV/AIDS is Associated with Depression and Subjective Neurocognitive Complaints But Not Neuropsychological Functioning." Journal of Clinical and Experimental Neuropsychology 25 (2003): 200-215

-Sadek, Joseph R., Vigil Ofilio, Igor Grant, and Robert K. Heaton. "The Impact of Neuropsychological Functiong and Depressed Mood on Functional Complaints in HIV-1 Infection and Methamphetamine." Journal of Clinical and Experimental Neuropsychology 29 (2007): 265-276