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Article Summary

Addictive Drugs And The Problems They Cause To The Human Brain

While looking at addictive drugs and the problems they cause to the human brain, it is essential to understand just how the brain works. In effect, the human brain is perhaps the most complex organ in your body.

A 3-pound mass of white and gray matter, the brain is at the core of all activity. As such, you need to use it to read, write, breath, respond to external stimuli, enjoy day to day activities, create artistic masterpieces, breathe, exercise, enjoy meals, procreate, and move - among many others.

To this end, the brain is responsible for regulating both your basic and complex functions. It can, for instance, empower you to respond and interpret all your experiences while simultaneously shaping your emotions, thoughts, and behavior.

To ensure its efficacy, the brain is comprised of a variety of parts that work hand in hand in a team effort. These different parts are responsible for performing and coordinating specific functions.

When you abuse addictive and intoxicating substances, therefore, they can effectively change how these parts of the brain work - parts that are responsible for most life-sustaining activities. They can also cause you to start abusing drugs compulsively - to such an extent that you develop an addiction.

But what parts of the brain are affected when you use intoxicating substances? Essentially, drugs can impact:

  • The limbic system that houses the reward circuit of the brain; this system links different brain structures responsible for regulating and controlling your ability to experience the sensations of pleasure; feeling pleasure, on the other hand, motivates you to repeat some of the basic behaviors and life functions that are crucial to your existence. You can activate the limbic system by healthy and life-sustaining activities like socializing and eating; however, addictive drugs can also activate it. Additionally, this system is responsible for how you perceive other emotions - both negative and positive - a fact that explains how drugs can alter your mood
  • The cerebral cortex that is divided into different segments that control particular bodily functions; these different areas will process the information from your senses; therefore, they enable you to taste, hear, feel, and see. The front part of this cortex (the forebrain or the frontal cortex) is the brain's thinking center; as such, it powers your ability to make decisions, solve problems, plan, and think
  • The brain stem that is responsible for controlling the basic brain functions that are critical to your life, including sleeping, breathing, and heart rate

How The Brain Communicates

As a communications center, the brain contains billions of nerve cells known as neurons. These networks of neurons act to convey messages among the different structures of the brain, the nerves inside your body (also known as the peripheral nervous system) as well as the spinal cord. All these nerves networks also regulate and coordinate everything you do, think, and feel.

Consider the following ways in which the different parts of your brain communicate:

a) Neuron to Neuron

Every nerve cell inside your brain conveys and receives messages that are sent in the form of chemical and electrical signals. After a cell has received a message and processed it, it transmits it to another neuron.

b) Neurotransmitters

Neurotransmitters are the chemical messengers of the brain. As such, these chemicals carry messages from one neuron to another.

c) Receptors

Receptors, on the other hand, are the chemical receivers of the brain. Neurotransmitters, to this end, will attach to specialized sites on the recipient neuron (referred to as a receptor).

Therefore, neurotransmitters and their receptors work like keys and lock - a highly specific mechanism that can ensure every receptor forwards the right message after interacting with the right neurotransmitter.

d) Transporters

The chemical recyclers in the brain are known as transporters. They can locate don neurons which release neurotransmitters. After that, they will recycle the neurotransmitters by bringing them back to the neuron which released them. In the process, they can shut signals off between neurons.

To communicate, therefore, brain cells known as neurons will release chemicals called neurotransmitters into the synapse or space found between it and the cell next to it. After that, the neurotransmitters will cross through the synapse and attach to the receptors or proteins on the recipient brain cell. This will cause a change to the recipient cell after the message has been delivered.

The Impact Of Drugs On The Brain

At this most basic, most drugs can be considered to be chemicals. As such, they affect your brain by tapping through the communication system. In the process, they will interfere with the way your brain neurons receive, send, and process information.

In particular, drugs like heroin and marijuana can activate these neurons since they have chemical structures that mimic natural neurotransmitters. Since they are similar in structure, the receptors will be fooled - which will allow the drug to attach themselves to the neurons and activate them.

However, although drugs mimic the chemicals in the brain, they will not activate the neurons the same way a natural neurotransmitter would. Instead, they will cause the network to transmit abnormal messages.

Other intoxicating substances like cocaine and amphetamine can compel the neurons in your brain to release natural neurotransmitters in abnormally large amounts. Alternatively, they could prevent your brain from recycling these chemicals - which it otherwise would. This causes a disruption that produces greatly amplified messages that ultimately disrupt the brain's communication channels.

The Pleasurable Effects Of Drugs

Most addictive drugs will directly or indirectly target the reward system of the brain by effectively flooding the entire circuit with dopamine - a neurotransmitter that is found in the parts of the brain responsible for regulating feelings of pleasure, motivation, emotion, and movement.

If this system is normally activated, it will reward your natural behaviors. However, if it is overstimulated with intoxicating drugs, it will produce euphoric effects. It is these euphoric effects that will strongly reinforce continued substance abuse - eventually teaching you to repeat the behavior over the long term unless you receive due treatment.

Additionally, the stimulation of the pleasure circuit of the brain can teach you to continue taking drugs. This is because the brain is naturally wired to ensure that you keep repeating some of the activities that are essential to sustaining your life - such as sleeping and eating. It does this by effectively associating these activities with reward or pleasure.

When this reward circuit gets activated, therefore, the brain will note that you are doing something important that it needs to remember. As such, it will teach you to repeat this action over and over again - sometimes without overthinking it.

Drugs of abuse will stimulate this same circuit. As a direct result, you will eventually learn to continue abusing these intoxicating and mind-altering drugs much in the same way you learned to perform life-sustaining activities like eating.

However, drugs tend to be more addictive in comparison to other more natural rewards. But why is this the case? Essentially, when you take a drug, it will release two to ten times the normal amounts of dopamine as other natural rewards like sex and eating would.

In some instances, this will happen almost immediately - especially if you inject or smoke drugs. Additionally, the pleasurable effects of such drug taking tend to last longer than those that natural rewards produce.

As a result, the effects of drugs on the pleasure circuit of the brain will dwarf those that you produce by engaging in naturally rewarding behavior. The effect of this powerful reward will strongly motivate you to take these drugs over and over again. This is one of the reasons why scientists claim that substance abuse is an activity that human beings learn how to do particularly well.

The Effects Of Ongoing Drug Abuse

If you continue taking drugs, however, they can effectively impair how your brain works. For the mind, there is a significant difference between drug rewards and normal rewards. This difference is so stark that it can be compared to someone shouting through a microphone and someone whispering.

In the same way that you would reduce the volume if your computer is too loud, your brain will adjust to the somewhat overwhelming surge in dopamine - as well as other neurotransmitters - by trying to produce dopamine in lesser amounts. It can also reduce the total number of receptors receiving signals.

The result is that the impact of dopamine on the brain's reward system will become unusually low. This could potentially significantly reduce your ability to experience the sensations of pleasure - both natural and drug derived.

This is one of the main reasons why most people who have become accustomed to abusing intoxicating and mind-altering drugs eventually find themselves feeling depressed, lifeless, flat, and utterly unable to enjoy the things that they once found pleasurable.

At this point, you would have to continue taking drugs over and over again to try and bring your dopamine levels and function to normal. However, continued substance abuse will only worsen the problem - a vicious cycle familiar to all addicts.

Additionally, you might often feel that you need to continue taking increasingly more massive doses of your preferred substances to achieve the dopamine high that has become familiar to you. This effect is known as building up a tolerance to drugs.

But how does drug abuse in the long term affect the circuits of the brain? Essentially, the mechanisms that are involved in developing tolerance will eventually cause profound changes in brain circuits and neurons. They can also potentially compromise the health of your brain in the long term.

For instance, the brain contains glutamate - another neurotransmitter responsible for influencing your reward circuit and natural ability to process information and learn. If you take drugs, they will alter the optimal concentration of their neurotransmitter. As a direct result, your brain might try to compensate and make up for this change. This could potentially impair your cognitive function.

In the same way, abusing drugs in the long term could potentially trigger some adaptations in non-conscious habits and memory systems. This is a type of learning - with conditioning being just one example.

It can, therefore, cue your daily routine or the environment that your brain has come to associate with the experience of substance abuse. Additionally, it could potentially trigger uncontrollable drug cravings any time you are exposed to any of these cues - even in situations when you do not have your preferred drug of abuse.

This is a learned reflex that tends to be extremely durable. It can also affect people who once abused drugs even after years of continued and sustained abstinence from intoxicating substances.

How Drug Abuse Changes The Brain

If you expose drugs of abuse to your brain in chronic ways, they can change the interactions between brain structures and the behaviors that are linked to your ongoing substance use. As such, these structures will not be able to inhibit and control these behaviors.

To this end, in the same way, that continued substance abuse might cause tolerance so that you need to take higher doses to produce the pleasurable effects that you desire, drugs can also cause you to become addicted.

Addiction, on the other hand, can drug you to start seeking out and taking drugs out of compulsion. It will also completely erode your ability to make highly informed decisions or control yourself while simultaneously creating strong impulses for you to continue taking drugs.

Understanding Drugs, Dopamine, And The Brain

Recent advances in the field of neuroscience are allowing scientists, doctors, and addiction treatment professionals to delve deeper into the functioning of the brain and to understand how addiction develops. In particular, these advances have taught us that the reward system of the brain is responsible for playing a major role in addiction - alongside other factors.

For a long time now, addiction has been stigmatized - with many people believing that those who are addicted lack self-control, morals, and willpower otherwise they should just stop abusing drugs. This is because millions of people continue experimenting with alcohol and drugs on an annual basis without developing an addiction.

However, recent findings in the field of neurobiology have been providing a better insight into the phenomenon of addiction. In particular, scientists have been studying the brain as well as its reaction to different intoxicating substances. This has allowed them to discover how drug abuse alters the chemical composition of the mind - to such an extent that they cause addiction.

But how does ongoing substance use affect the brain? As we mentioned earlier, the mind is at the center of all human activity. Therefore, it is involved in all aspects of thinking, feeling, and doing.

As a communication center for your body, the brain is also responsible for continually sending and receiving messages to the different parts through transporters, receptors, neurotransmitters, and neurons.

When you take addictive drugs, however, they will interrupt the normal pathways of communication that your brain uses. According to NIDA (abbreviation for the National Institute of Drug Abuse), drugs are comprised of chemicals that can affect your mind. As such, drugs will tape into the communication system of the brain and interfere with how neurons would normally process, receive, and send information.

In particular, some drugs can activate the neurons of the brain because they have a chemical structure that resembles natural neurotransmitters. This structural similarity will fool the receptors and allow drugs to attach to the neurons and activate them.

However, even though substances mimic the natural chemicals in the brain, they will not activate the neurons as a natural neurotransmitter would. As a result, they will cause the network to start transmitting abnormal messages.

Other drugs will also cause the brain's neurons to release natural transmitters like dopamine in abnormally large amounts as well as prevent these brain chemicals from being recycled how they normally would be. This causes a disruption that effectively produces greatly amplified messages that will ultimately disrupt the communication channels of the brain.

The Reward System Of The Brain

If you engage in pleasurable activities like socializing and participating in sexual encounters, achieving fame, making money, or taking a delicious meal - or even using mood-altering substances like marijuana - your brain will process all these types of pleasure in pretty much the same way.

In effect, all these pleasurable activities will cause the brain to release dopamine - a natural neurotransmitter - into clusters of nerve cells referred to as the nucleus accumbens (clusters that are located right below your cerebral cortex). This part of your brain is closely linked to feelings of pleasure - which is why scientists refer to it as the pleasure or reward center of the brain.

This reward system ensures that you continue repeating the activities that are essential to sustaining your life - such as mating, drinking water, eating food, and more. However, when you drink alcohol or take drugs, it will send this system into direct overdrive.

But how do drug abuse and drinking affect the reward system? Essentially, intoxicating and mind-altering substances like drugs and alcohol will cause the brain to release dopamine in excess - leading to a massive surge in this neurotransmitter. They do this in ways that compel the brain to produce far more of this neurotransmitter than it otherwise would if you participated in naturally rewarding activities like eating.

Additionally, some factors effectively contribute to the addictive potential of a drug. These factors include, but are not always limited to:

  • The strength or intensity of the release of dopamine
  • The speed at which the drug promotes the release of dopamine
  • The reliability of this release of dopamine

It is for this reason that people tend to inject or smoke most intoxicating drugs of abuse. This modes of administration allow the drug to find its way to the brain at higher speeds and with higher intensity.

In turn, these drugs will cause the brain to release a burst of dopamine in rapid and intense succession thereby giving your body such feel-good sensations that your mind will start wanting more of the experience after it starts wearing off.

Since this pleasure will be much higher than you derive from natural rewards, your brain might start wanting more of the drug you took so that it can replicate this sensation. This is because drugs act on the parts of the brain that encourage you to repeat other natural activities by triggering dopamine.

The Effects Of Drugs On The Brain And The CNS

According to the 2014 NSDUH (abbreviation for the National Survey on Drug Use and Health), more than 30 million Americans were using illicit drugs. This goes to show that they had abused these drugs within a month of the survey.

This number is significant because these intoxicating substances interact with the body and the brain to alter behavior, emotions, and moods. They do so by changing the chemical composition of the mind and your perceptions as well as by impacting how you interact with the environment around you.

These mind-altering drugs, to this end, might speed up or slow down the CNS (central nervous system) as well as all the automatic functions that are necessary to your continued living - including body temperature, heart rate, respiration, and blood pressure.

Drugs of abuse can impact the levels of the chemical messengers of the brain (known as neurotransmitters). In particular, they might affect:

a) Serotonin

Serotonin is a natural neurotransmitter in the brain that is responsible for regulating emotions and stabilizing moods.

b) Norepinephrine

Norepinephrine is similar to adrenaline in the sense that it is often referred to as a stress hormone. It acts by speeding up the CNS as a response to the fight or flight response that is natural to all human beings. This neurotransmitter can also hone your attention and focus as well as increase your energy levels.

c) Gamma-aminobutyric acid (or GABA)

GABA is the brain's natural tranquilizer. As such, it can lower your levels of anxiety, mitigate your stress and depression responses, and slow down the functioning of your CNS.

d) Dopamine

Last but not least, dopamine is responsible for enhancing pleasure and regulating mood. This neurotransmitter is also involved with attention, motivation, reinforcing behaviors, reward, and movement.

To this end, when you abuse mind-altering and intoxicating substances like heroin and methamphetamine, they can effectively disrupt different regions of your brain. According to NIDA, drugs can affect the cerebral cortex, the limbic system, and the brain stem.

Additionally, the more you abuse drugs, the more they will continue affecting the circuitry and chemicals of the brain. Eventually, this could potentially cause you to experience tolerance and build up dependence on these drugs. This means that you will go into withdrawal mode when these drugs have been processed out of your body. Some of the signs that you would have become addicted to a drug include withdrawal symptoms, dependence, and drug cravings.

According to ASAM (or the American Society of Addiction Medicine), addiction is a chronic condition that affects brain circuitry and chemistry. In the process, it leads to compulsive behaviors of seeking and using drugs.

But what are the most addictive drugs? Consider the list below:

  • Alcohol
  • Benzodiazepines like clonazepam (or Klonopin), alprazolam (or Xanax), lorazepam (or Ativan), and diazepam (or Valium)
  • Cocaine
  • Ecstasy or Molly
  • Hallucinogens and other dissociative drugs
  • Heroin
  • Ketamine
  • LSD
  • Marijuana
  • Methamphetamine
  • OxyContin or MDMA
  • PCP
  • Prescription amphetamines like methylphenidate (or Ritalin) and amphetamine and dextroamphetamine (or Adderall)
  • Prescription Opioids like hydromorphone (or Dilaudid), methadone, fentanyl, hydrocodone and acetaminophen (or Vicodin), and oxycodone (or OxyContin)
  • Stimulants
  • Synthetic Cannabinoids

Understanding Drug Abuse And Addiction

All addictive drugs can affect your behavior as well as your brain. This is why addiction is now considered to be a chronic condition. After you develop an addiction, therefore, you might no longer be able to resist the intense urge to continue using drugs - irrespective of the amount of harm that drugs can cause to you.

However, drug addiction does not just require you to take illegal drugs like cocaine and heroin. In fact, you can also develop a chemical dependence in your brain to legal drugs like opioid pain relief medications, nicotine, and alcohol.

When you start taking drugs, you might first choose to experiment while trying to seek how they will make you feel. At this stage, you might even be able to control how often and how much of a drug you take.

Over time, however, drugs will completely alter the working mechanism and chemical structure of your brain. These are all psychological and physical changes that might end up lasting over the rest of your life. This is dangerous because drugs can cause you to develop damaging and harmful habits and behaviors as well as lose your self-control.

Are drug abuse and addiction different? Essentially, drug abuse occurs when you use illegal and legal substances in ways that you should not. For instance, you might receive a prescription for an intoxicating medication and end up taking more than the dose your doctor recommended. Alternatively, you could steal another person's prescription drugs.

When you abuse drugs, they can cause you to avoid reality, ease your levels of stress, and enable you to feel good and pleasurable. At this stage - earlier on in your substance abuse - you might still be able to stop using drugs altogether and change your habits.

However, you might also get to a stage when you find that you need to use drugs has become compulsive. When you reach this point, you might not be able to stop using even if continued substance abuse starts putting your life if mortal danger as well as causing emotional, financial, and productivity problems in your life. Even if you desire change and try to quit, you will often find that the urge to obtain and use drugs start filling up almost every minute of your waking hours.

Addiction develops because of how drugs affect the brain. In particular, the brain is naturally wired in such a way that it will compel you to repeat some habits and experiences - particularly those that cause you to feel good about yourself. This way, you will have the motivation to repeat these behaviors over and over again.

Addictive drugs, to this end, effectively target the reward system of the brain. They so do by flooding it with dopamine - thereby triggering feelings of intense happiness and pleasure. Eventually, you will continue taking these drugs in search of these effects.

With time, however, your brain will start getting used to the excess levels of dopamine inside it. This means that you will have to continue taking drugs more frequently and at higher doses to achieve the original pleasure that you desire. Simultaneously, the other things that you used to enjoy - like spending time with loved ones and eating delicious food might provide you with lesser feelings of pleasure.

After using drugs in the long term, they can effectively change the circuits and chemical systems in your brain. At this point, you might find that your ongoing substance abuse starts hurting and impairing your:

  • Ability to learn
  • Decision making
  • Judgment
  • Memory

In combination, all these changes in your brain might continue driving you to seek and use drugs to such an extent that you are unable to control this compulsive behavior unless you seek appropriate treatment.

But who has the highest likelihood to start using drugs and develop an addiction? Essentially, some factors might increase your risk factors for addiction. These factors include:

  • Early drug use
  • A family history of substance abuse
  • Having troubled relationships
  • The existence of mental disorders

Getting Help

Now that you understand addictive drugs and the problems they cause to the human brain, it is imperative that you seek treatment for your ongoing substance abuse and addiction before they get out of hand and you harm yourself, others, or even lose your life.

Today, many rehabilitation facilities provide help to people who have been having trouble with addictive drugs - both on an inpatient or residential and an outpatient basis. Check into one of these centers today to get the medical assistance you need to overcome your substance abuse.

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