Neurotransmitters and Behaviour Essay

Alzheimer’s disease known to be a neurological disorder of the central nervous system is an irreversible disorder in which brain cells deteriorate resulting to loss of our cognitive functions, primarily memory, movement coordination, reasoning and judgment, and pattern recognition. In its advanced stage, all memory and mental functioning could be lost (Healthcommunities.com, 2016). This disease is known to be caused by parts of the brain shrinking (atrophy), which destroys the structure and function of particular areas of the brain (Nhs.uk, 2016). Although the exact cause to this process is not known, research suggest that in the brains of patients with Alzheimer 's disease, scientists have found amyloid plaques (abnormal deposits of protein), neurofibrillary tangles containing tau and acetylcholine a chemical imbalances (Nhs.uk, 2016).

Experts believe bipolar disorder is caused by an underlying problem with specific brain circuits and the balance of brain chemicals called neurotransmitters (WebMD). There are five brain chemicals noradrenaline (norepinephrine), serotonin, dopamine, oxytocin, and endorphin. Noradrenaline and serotonin are the most common chemicals linked to psychiatric mood disorders such as depression and bipolar (WebMD). Dopamine is linked to the pleasure system in the brain (WebMD). When a disruption happens to the dopamine system connects to psychosis and schizophrenia (WebMD). If there is too much dopamine in one place, it can cause psychosis. Dopamine motivates us (Deans, 2011). Dopamine is linked to everything, metabolism, evolution, and the brain (Dean, 2011). Serotonin is connected to many different body functions including sleep, wakefulness, eating and impulsivity (WebMD). Researchers believe that abnormal brain functioning of brain circuits that involve serotonin as a chemical messenger contributes to mood disorders (WebMD). Oxytocin is a hormone commonly associated with childbirth and breastfeeding. Oxytocin plays a critical role in social and emotional behavior. Oxytocin increases the susceptibility to feeling fearful and anxious during stressful events (NWU, 2013).

The water-soluble neurotransmitters, on the other hand, only last for seconds (3). This persistance of the stress hormones makes it hard for the brain to return to its natural, unstressed state.

A neurotransmitter is a chemical messenger that travels across the synapse between a neuron and another neuron, muscle fiber, or gland. Hormone is a chemical messenger of the endocrine system that is released by a gland or organ and travels through the blood. Neurotransmitter and hormone both compare because they both are chemical messenger, both chemicals are released from vessels into the surrounding fluid by similar mechanisms. They both work by binding to receptors on target cells. Neurotransmitter and hormones are very important systems, which regulate the various activities of the body, and are dependent on the release of special chemicals. Furthermore, the tissues in the Central Nervous System produce some hormones, as well as the neurotransmitters. What sets neurotransmitter and hormone apart? Neurotransmitters belong to the nervous system, however hormones belong to the endocrine system. Hormones and neurotransmitters are engendered differently; hormones are engendered by endocrine glands while neurotransmitters are engendered by neurons. The transmission of neurotransmitters is across the synaptic cleft, whereas that of hormones is by blood. Hormones are able to regulate their target organs, whereas neurotransmitters are able to stimulate the postsynaptic membranes. The action of neurotransmitters is extremely fast, which could be up to a few milliseconds. In contrast, effect of hormones could be lost for a long period, which could be in the range of few seconds to a few days.

The brain uses neurotransmittors to tell your stomach to digest and your heart to beat. Neurotransmittors are also responsible for balancing mood, sleep, and even weight. If the chemicals in our brain become out of balance, we can suffer sever adverse affects that make life both challenging and debilitaing as we strive to function.

Dementia is a syndrome which is progressive in nature, characterized by impairment of memory and loss of intellectual ability.1 Decreased level of Acetylcholine in the brain, neuro-inflammatory reaction, rise in the oxidative stress and hypercholesterolemia have been reported to play an important etiological role in the memory decline.2 Alzheimer’s Disease (AD) is the most common form of dementia which is a progressive and a neurodegenerative disease characterized by the presence of senile plaques rich in insoluble aggregates of β amyloid and neurofibrillary tangles in the brain. AD has been estimated to account for 50–60% of dementia cases in persons over 65 years of age worldwide.3 Alzheimer’s Disease International

Amyloid beta is also associated with reduced levels of the neurotransmitter protein acetylcholine. An acetylcholine receptor is an integral membrane protein that forms part of essential processes like memory and learning, which are progressively destroyed in patients with Alzheimer's disease (Qué es la enfermedad de Alzheimer?, n.d., para. 6).

Alzheimer’s is a disease where neurotransmitters, acetylcholine, or the brain’s chemicals break connections with other nerve cells causing the cells to die off, the effects of this are irreversible. The loss of these cells result in loss of thinking and language skills, unpredictable behavioral changes and eventually the inability to carry out the simplest tasks. Although there is no known cause for Alzheimer’s, researchers have found a genetic link. Alzheimer’s first symptoms usually appear when a person is between forty and fifty years of age. Alzheimer’s is a devastating disease that initiates in the brain, drastically decreasing the quality of life as well as life expectancy in millions of people around the world.

7- Acetyl Choline – chemical messenger in the brain which makes “neurones spark better and speak to each other more clearly.” (Bryden, 2005, p. 16) Small amounts of acetyl choline when you have dementia so brain does not work as fast. Drugs called acetyl cholinesterase (AChE) inhibitors stop the breakdown of acetyl choline so you have increased amounts in

Earlier research was done on the inhibition of amyloid β, but a relatively new approach is to find inhibitors for acetlycholinesterases enzyme (AChE). The action of AChE results in the blockage of transmission of acetylcholine (ACh), hence hyperphosphorylating the tau protein which affects the breakage of amyloid precursor protein(APP), which firther results in the increase in amyloid β. The binding of AChE causes decrease in the binding of ACh to muscarinic recptor and nicotinic receptors (Francis, Palmer, Snape et al., 1998). A recent study has shown that ACh does not only have cognitive functions, it regulates the

Research indicates that cases of Alzheimer’s disease involve “…damage to improper function of on or more of these brain areas…: the prefrontal lobes, the hippocampus, amygdala, and diencephalon (van der Flier et al., 2005; Caine et al., 2001). Researchers have also identified biochemical changes that occur n cells as memories form; studies suggest that acetylcholine and glutamate are in low supply or at lease function differently, in the brains of Alzheimer’s victims (Chin et. al.., 2007; Akairke,

This paper explores various elements and issues related to Alzheimer’s disease (AD). Topics briefly detailed include etiology, symptomology, diagnosis, neuroanatomy, neurotransmitter systems involved and treatments that focus on neurotransmitters. Emphasis is placed on such topics as cognitive decline and dementia; neurological change; and changes to neurotransmitters and synapses. Details concerning diagnosis and treatment are brief, but do elaborate somewhat on present studies into addressing specific changes in the brain through pharmacological approaches, cognitive therapies and physical exercise. At present, there are limited resources available for treatment of AD. While research continues to seek out more effective therapies, it appears that most only have little to moderate efficacy on this elusive disease.

Biological Theories. The monoamine neurotransmitters—norepinephrine, dopamine, serotonin, histamine—are the main focus of theories regarding the cause of depression. However, the focus is not on a single neurotransmitter but on the “studying neurobehavioral systems, neural circuits, more intricate neuroregulatory mechanisms” (Kaplan Sadock 531).

In neurotransmitter dysfunction, the biological approach to depression explains low levels of the neurotransmitter serotonin. This has been linked with many forms of dysfunctional behaviour such as anxiety, excessive anger, poor social functioning and other mood disorders.

(3) While successful drug therapies which act on neurotransmitters in the brain imply that depression is a neurobiological condition (4), the fact that such medications do not help about 20 percent of depression-sufferers seems to show that not all depression is due to such imbalances. Rather, depression is not caused by one single factor; it is most often caused by many different things. Genetics, biochemical factors, medicines and alcohol, developmental and other external factors, and relationships, marriage and children all have effect on the development of clinical depression. (5) The strongest hypotheses on the pathways to depression are in decreases in the activity of specific neurotransmitters, or the overactivity of certain hormonal systems. (3)