How the brain is affected by substance abuse
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There are many analogies for the human brain. Some sources compare the organ to a computer, as different functions are compartmentalized to specific areas that are wired together. Other experts describe the mind as a collection of roads and highways due to the continuous signal traffic that shoots back and forth between neurons and the rest of the body. One should view the brain with these perspectives in mind when getting caught up in the grips of addiction. Illicit substances, prescription drugs and the extreme effects both categories have on behavior can also be traced back to particular paths and areas of the brain.

To paint a more detailed image of how the brain is impacted by addiction, it’s important to know the key components involved. The first are the acting neurological and chemical substances, also known as neurotransmitters. Different brain cells or neurons communicate with each other through these transmitting particles and together they make up the entire circuitry of the brain. In regards to drug dependency, only certain neurotransmitters are tied to the rewards associated with substance use:

  • The primary neurotransmitter directly involved with reward is called dopamine. The natural release and reception of this element in the brain brings about pleasure and other emotional regulations.
  • Another important neurotransmitter is serotonin, which has many roles in the human mind, including the regulation of one’s body temperature, sleep patterns, mood, appetite and pain processes. Most drugs administered by a clinician that are used to treat depression today work by increasing serotonin levels in the brain.
  • Lastly, glutamate and gamma-aminobutyric acid (GABA) are the other major transmitters of the brain that control inhibitory and excitatory responses of the body.

Through the specific pathways traveled by these transmitters, a person will develop implicit links to the thoughts and behaviors that lead to rewarding experiences. This system, therefore, reinforces productive behaviors and inherently motivates people to pursue these actions. In the case of an abusive or addictive relationship with drugs or alcohol, these reward systems are accessed with high and forceful demands that result in extreme levels of pleasure or euphoria. In time, the addicted individual will be conditioned to continue drug use in order to achieve the same, intense feelings. This conditioning marks the shift in a person’s internal reward system to only acknowledge a need for the drug. However, these neurological connections and communications only make up a part of the stage that the neurotransmitters act upon.

The other part of the equation is the various centers of the brain that communicate through these pathways and the neurotransmitters that travel through them. For dopamine, three distinct pathways involve the transfer of the pleasurable neurochemical. The substantia nigra and the striatum make up the nigrostriatal pathway that is mainly responsible for motor control. The mesolimbic and mesocortical pathways consist of a set of locations known as the ventral tegmental area that are connected to the nucleus accumbens, amygdala, hippocampus and prefrontal cortex. This network of the brain is involved with memory, motivation, emotion and most importantly the reinforcement of addictive behaviors. The third dopamine path is called the tuberoinfundibular pathway, which connects the hypothalamus to the pituitary gland. This crucial connection influences hormone regulation, behaviors related to different hormones and various senses. When a person gets an unnaturally high dose of dopamine from a drug, a wide range of negative impacts can occur due to the different functions these different areas and pathways control.

In short, neurotransmitter systems are intertwined. The areas involved with serotonin production are the raphe nuclei, which release and send the substance to the farthest areas of the brain as well as the spinal cord. Similarly, glutamate and GABA are found all over the brain as well. Although illicit drugs often affect different parts of the brain’s reward system, they share increases of the same neurotransmitters, as the drugs often affect more than one pathway to reach high levels of euphoria. Whether it is dopamine, serotonin or GABA, each of these are influenced in dangerous and simultaneous ways during a serious addiction.

With so many sectors of the brain drastically affected by drug use and subsequent addiction, one can see how a person’s thoughts, emotions and behaviors are easily influenced and why it is important to treat the addiction before it gets out of control. If you or someone you love is suffering from an excessive dependency to a substance of any kind, please contact Sovereign Health Group. Live chat online or call (866) 819-0427 to speak immediately with a member of our team.

Written by Lee Yates, Sovereign Health Group writer

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