Reward Circuit

To understand addiction further, it is important to look at how drugs have neurological effects in a human body. Drugs can be ingested in various ways; while some are taken orally, some are smoked (cannabis) while others are injected directly into the blood stream (Heroin). Once in the body, they mainly affect the reward pathway in the brain, known as the dopaminergic pathway, which in turn gives pleasure. Even though all drugs affect the reward and motivation pathways in the brain, their speed depends on the way the drug has been consumed. Over constant use of drugs, the cognitive functions are impaired as the effects become more prominent in learning, memory

It is believed that certain individuals are predisposed or vulnerable to addiction based on biological, psychological and social influences. The euphoric high produced by many addictive substances is the result of overstimulation of the “pleasure center” of the brain. This is the same area that controls emotions, fear, self-control and overall feelings of wellness. The presence of these foreign chemicals creates a response that the brain will crave as soon as it fades. The brain’s chemistry works against its own health, as it rewires its decision making faculties around the primary goal of finding and taking more of the drug” (1). Many people mistakenly believe that psychological addiction is somehow less serious or real than physical addiction. The psychological aspects of addiction are much more challenging to repair and recover from than the physical addiction. Psychological addiction can last for years or even a lifetime.

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

According to the biological perspective, drug use may start off as casual, but through continued use, it produces changes in the brain that influences the onset and maintenance of drug addiction. (Horvath et al., 2013). Drugs have their most prominent effects on the function of neurotransmitters. Almost all major drugs of abuse activate the reward system and cause a flood in the levels of dopamine which is a neurotransmitter that is involved in pleasure. As a result, not only do people learn to associate drug use with pleasure, but the brain also starts to reduce its own natural dopamine production in adjustment to the levels of dopamine produced by the drugs. This is called tolerance, and the consequences of tolerance are highly influential

When activated at normal levels, this system rewards our natural behaviors. Overstimulating the system with drugs, however, produces euphoric effects, which strongly reinforce the behavior of drug use—teaching the user to repeat it. (1)

Technology has allowed us to gain greater insight into the effects that these substances have on the body, and the research largely affected the ways in which I thought about addiction. The largest influencer on my opinions on addiction were the arguments originating in the research on neurobiology, with my interest focusing largely on neurotransmitters and processes such as the down-regulation of receptor sites in response to the overproduction or inhibited reuptake of certain neurotransmitters (Inaba & Cohen, 2011). To me it would make sense that these actions would encourage the user to continue using whatever substance caused the changes to happen in the first place. In their article arguing for medication-assisted therapy for inmates in the criminal justice system, Bruce and Schleifer (2008) summarized my ideas surrounding addiction: “In essence, the overwhelming physical and psychological reward that comes from heroin derails a neurobiological system designed to preserve the individual” (p. 18). Rather than being limited just to heroin, this was my opinion on all addicting psychoactive

Across all addictions, there is a central theory as to how such an addiction can occur. The common mechanism of all addictive substances is the activation of the brain’s “reward system”, made up of dopaminergic neurons of the midbrain and their extensions to the limbic system (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3272277/). This system is normally used in advancing evolutionary fitness promoting activity, such as sex, food, or social interactions (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3272277/). In such normal natural behaviors, the reward system activity is relatively brief and weak. However, addictive substances abuse the system’s circuitry, causing

What is addiction? The most common definition is the condition of being addicted to a particular substance, thing, or activity. Addiction is so much more than that. People with addiction may not realize that their problem is out of control and could be causing problems for themselves or others around them. Addiction becomes an all-time thing and interferes with usual life responsibilities like relationships, social life, work, and health. People that are struggling with addiction, often cannot quit on their own. Addiction is an illness that entails treatment,

Naltrexone is an opioid receptor antagonist. It had been thought to modulate reinforcement-driven behavior by blocking dopamine release. Yet, its effects on behavior has not been previously tested in human models of cue-induced craving. Therefore, Courtney et al. manipulated usage of naltrexone to establish its effect on drug craving. As their particpants, Courtney et al. studied 24 non-treatment-seeking individuals who met the criteria for methamphetamine addiction (both in DSM-IV and DSM-5). The subjects were administered 3-day medications. Participants in the naltrexone condition received 25 mg does on the first day, followed by 50 mg dose on the second and the third day, whereas subjects in the control condition received placebo pills. Abstinence from alcohol and substance during the 3-day period was required and participants were assessed by urine toxicology screen. The participants

Ideas about addiction have mainly been developed from neurobiological evidence and data from studies of learning behavior and memory mechanisms. They overlap in some aspects and are not mutually exclusive. None of them can explain all aspects of addiction. Generally, addictive drugs can act as positive reinforcers or as negative ones. Environmental stimuli associated with drug use itself can also induce a conditioned response in the absence of the drug.

Drug seeking behaviors comes from medical patients who abuse prescription drugs. They tend to visit physician and exert escalated pressure to obtain prescription drugs. Other drugs such as cocaine may disrupt the brain function through three way alike snorting, smoking, and injecting cocaine is how it inter the blood stream and all area of the brain. However, its euphoric effects are mediated in certain areas. For instance, prescription drugs are oral alike marijuana, Acetaminophen, Adderall, Xanax, Codeine, Oxycodone, Ibuprofen 800 these prescription reaches or become associated with the reward pathway. Meanwhile that is why each prescribed drug is provided with a certain dosages, possible drug interactions, side effects, and contraindications

Among the numerous definitions for addiction, there lies yet another to define it from a biochemical perspective. Milkman (1983) defines it as “self-induced changes in neurotransmission that result in social problem behaviors." This definition encompasses the psychological, biochemical and social aspects of addictive processes. It is not limited to substance abuse and can be applied to any activity characterized by compulsion, loss of control and continuation of the substance despite harm. This has helped investigators gain a better understanding of the nature of addiction.

Substance addiction can hugely impact on a person’s thinking, functioning and behaviour. Whilst depressant drugs such as alcohol and opioids slow down your central nervous system (CNS), stimulants such as cocaine or amphetamine increase the activity of the CNS, leading to higher blood pressure, heart rate and increased alertness. Repeated abuse of the substance leads to tolerance and withdrawal, in turn this leads to the user showing signs of irrational behaviour. Another form of substance abuse is hallucinogens; they can cause powerful changes in sensory perceptions. It works by binding to the serotonin receptors, these neurons control visual information and emotions, and this can lead to various effects on the user. Neurobiology can help us understand the reasons for addiction and the effects they have on us. Groman and Jentsch (2012) discuss key issues of differentiating the causes and consequences of addiction through neuroimaging and behavioural research on monkeys, they found that the dysfunction of the dopamine

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.