Arguments In The Dopamine Reward System

It is shown in studies of the human brain that dopamine in released when that high is hit and that what makes people what to continue. “Dopamine is a compound present in the body as a neurotransmitter and a precursor of other substances including epinephrine.” People can begin to chase this feeling and want it again and again. It is shown that dopamine is released when someone does something good such as hit a homerun in baseball even when they make a big

of the chemical messenger dopamine, which affects parts of the brain that control reward and

This research paper will evaluate the biological aspects of addictive substance or behavior and how it affects the brain and organs. Biological aspects include dopamine levels that are replaced in the brain due to the reward system being overtaken and the absorption rate of the drug once it is ingested will be discussed. The biological aspects are extensive and permanent if the individual does not get the help they need. Furthermore the clinical issues of addictive substance or behavior will be discussed along with medical treatments and ethical issues. This includes treatments such as counseling

Of the six most common neurotransmitters, dopamine is probably the one people know the most about. Dopamine is involved in controlling the reward and pleasure system in the brain. It allows us to recognize rewards and helps give us the ability to go after them. Learning, behavior, and cognition are also affected by dopamine levels. As with anything, if you have an imbalance, then bad things can happen. Parkinson’s disease can be caused by low dopamine amounts. People who have low dopamine levels can be addicted to substances easier.

Dopamine is produced in the substantia nigra, as well as in the adrenal glands and is transmitted to the basal ganglia along a connecting neural

The primary function of the nucleus accumbens in the brain is to be act as somewhat of a "reward circuit". Actions that are registered in our brains as a rewards include activities such as taking drugs, having sex, making money or eating food (Hall). Because of this message sent to our brains that are saying we have been rewards, dopamine and other neurons are triggered. According to Psychologytoday.com, “Dopamine is a neurotransmitter that helps control the brain's reward and pleasure centers. [It] helps regulate movement and emotional responses, and it enables us not only to see rewards, but to take action to move toward them” (Psychologytoday.com). In other words, dopamine is another type of neurotransmitter that releases a “feel good” sensation in our bodies when we do something that brings us pleasure. This dopamine and other neurons have the ability to move themselves closer to the nucleus accumbens. After their arrival, they activate themselves and this activation results in the rise dopamine levels.

The nervous system is broken down into two parts, The Central Nervous System and the Peripheral Nervous System. Each System has its own function but works together to engage the brain and body in all aspects of life such as bodily functions, sensory processing, learning, reasoning, creativity, experiences and emotions. Looking further into the nervous system is where neurons and neurotransmitters come into play. This system of neurotransmission is responsible for ensuring that the Central Nervous System and the Peripheral Nervous system communicate effectively. Sending and receiving messages about the body internally and externally. Part of this process called neurotransmission includes our desires and motivations, which we can relate to as the rewards pathway. Located in the center of the brain the rewards pathway can be affected by natural and necessary pleasures as well as the behaviors surrounding pleasure from unnaturally occurring pleasures such as drugs, or other addictive activities.

Some dopaminergic (i.e., dopamine-releasing) neurons run from the substantia nigra to the corpus striatum; their loss gives rise to the clinical manifestations of Parkinson's Disease (Korczyn 1994); others, involved in the rewarding effects of drugs and natural stimuli, run from the mesencephalon to the nucleunucleus accumbens.

In the research presented by Howes and Kapur (2009), they have pointed out a possible concern to invalidate the dopamine hypothesis in schizophrenia as current PET studies did not holding a firm position in measure the dopamine level, they were more to a postulation of a generated estimation from the data. Furthermore, Howes and Kapur (2009) also stressed that the role of dopamine could be circumvented by using the antipsychotic drugs which effectively to the psychotic symptoms but neutral to the dopamine system, thus the role of dopamine will be less critical in schizophrenia. This is because most of the recent antipsychotic researches only prove that dopamine merely contributed in providing a solution in alleviating the psychosis-liked-symptoms but those symptoms are not the symptoms only existed in schizophrenia.

The mesolimbic reward system is typically stimulated by life-sustaining and pleasurable stimuli such as food, sex, alcohol, and drugs. The mesolimbic system is a complex interaction of multiple components of the brain including the cerebral cortex, locus ceruleus, nucleus accumbens, and the ventral tegmental area. This reward system is responsible for perception of both physical interaction with our environment and life-sustaining actions. Upon activation, the mesolimbic system releases neurotransmitters, primary of which is dopamine.

Dopamine plays important roles in the brain and body. In the brain, dopamine functions as a neurotransmitter involved in reward-motivated behavior, motor control and controlling the release of various hormones. Dysfunctions of the dopamine system have been associated several important diseases including Parkinson's disease, attention deficit hyperactivity disorder, schizophrenia, and addiction [3]. Dopamine also functions in blood vessels, kidneys, pancreas, the digestive system, the immune system, and the blood vessels.

Schizophrenia is a Psychological disorder that impacts the person 's ability to process thoughts, emotions and action. Schizophrenia symptoms are categorized as cognitive, positive and negative symptoms. There has yet to be a confirmed singular cause of schizophrenia. The dopamine hypothesis is a theory that attributes the cause of schizophrenia to an increase in dopamine levels. The antipsychotic medication mentioned in this theory is beneficial in the treatment of the symptoms of schizophrenia. Although the medication that treats increased dopamine levels it does not affect other

There is an understanding that motivation is a driving force on behavior, but what remains unknown is where the purpose and execution of a motivated behavior converge within the brain. The hypothalamus plays an essential role in the integration of sensory information to direct motivated behaviors that maintain homeostasis in the body. A behavior that largely results from motivation is feeding, which has a reinforcing and rewarding property that stimulates the want for food. Feeding behavior illustrates regulation at the level of the hypothalamus a want supported by the dopamine reward system, and a relationship between food and mood provided by serotonin.

The complexity of the human brain creates mystery when determining the influence of neurophysiological factors and their role in the process of addiction. There is a proposed relationship between drug addiction and the mesolimbic dopamine system, with the mesolimbic pathway from the ventral tegmental area to the nucleus accumbens considered the ‘reward centre’ of the human brain (Alcohol Rehab, 2011). A release of dopamine is necessary for ‘reward’ which is hypothesised to initiate the addiction cycle by providing positive reinforcement for drug self-administration (Feltenstein & See, 2009). Methamphetamine triggers the release of dopamine from synaptic vesicles which flood the synaptic cleft activating feelings of euphoria, well-being

“The overstimulation of this reward system, which normally responds to natural behaviors linked to survival (eating, spending time with loved ones, etc.), produces euphoric effects in response to psychoactive drugs. This reaction sets in motion a reinforcing pattern that “teaches” people to repeat the rewarding behavior of abusing drugs ”(“Understanding Drug Abuse). Using addictive drugs floods the limbic brain with dopamine, taking it up to as much as five or ten times the normal level. A person with elevated dopamine levels now has a brain that begins to associate the substance with an outside neurochemical reward (“Your Brain on Drugs”). As a person continues to abuse drugs, the brain adapts to the overwhelming surges in dopamine by producing less dopamine or by reducing the number of dopamine receptors in the reward circuit. The result is a lessening of dopamine’s impact on the reward circuit, which reduces the abuser’s ability to enjoy the drugs, as well as the events in life that previously brought pleasure. The decrease in normal dopamine levels encourages the addict to keep abusing drugs in an attempt to bring the dopamine function back to normal, except now larger amounts of the drug are required to achieve the same dopamine high, an effect known as tolerance (“Understanding Drug Abuse ). That is what leads to the state of addiction, which leaves the person in a cycle of craving, using, withdrawal, and relapse.