Impact of Substances on the Brain

How do Substances Affect the Brain?

Drugs and alcohol affect three primary areas of the brain: the brain stem, the limbic system, and the cerebral cortex. When substances enter the brain, they interfere with its normal processing and can eventually lead to dramatic changes in the neurons and brain circuits. These changes can still be present even after an individual has stopped taking drugs.

There are several ways the drugs work in the brain:

Neurotransmitters

Some drugs, like marijuana and heroin, have chemical structures that mimic those of a neurotransmitter that naturally occurs in our bodies. The drugs can deceive our brain’s receptors, lock onto them, and activate nerve cells. Because these drugs do not function like natural neurotransmitters, the neurons end up sending abnormal messages through the brain.

Other drugs, such as cocaine and methamphetamine, cause nerve cells to release too much dopamine, which is a natural neurotransmitter, or prevent the normal recycling of dopamine. This leads to exaggerated messages in the brain, causing problems with communication channels.

When some drugs of abuse are taken, they can release 2 to 10 times the amount of dopamine that natural rewards, such as eating and sex, do.

Long-Term Brain Changes

Drug use can eventually lead to dramatic changes in neurons and brain circuits, which can lead to certain health conditions. These changes can still be present even after the person has stopped taking drugs.

After repeated drug use, the brain starts to adjust to the surges of dopamine. As a result, dopamine’s impact on the reward circuit of the brain of someone who abuses drugs can become abnormally low, and that person’s ability to experience any pleasure is reduced, causing them to become dependent on the drug to get the dopamine they need. d.

Studies have shown some deterioration of the brain’s white matter due to heroin use, which may affect decision-making abilities, the ability to regulate behavior, and responses to stressful situations.

The relationship between opioid overdose and depressed respiration (slowed breathing) has been confirmed, and this can affect the amount of oxygen that reaches the brain, a condition called hypoxia. Hypoxia can have short- and long-term psychological and neurological effects, including coma and permanent brain damage.

Some drugs of abuse, such as inhalants, are toxic to nerve cells and may damage or destroy them either in the brain or the peripheral nervous system.

Overall, long-term use of most drugs can cause cognitive impairment, brain growth and development issues if used as an adolescent, and may trigger mental health issues. Long-term drug use can also cause a change in one’s interests or activities, their ability to do their job, create financial issues, relationship issues and overall health. Many drugs, such as alcohol, can lead to further health issues, like liver disease or a weakened immune system. Long-term drug use also makes the withdrawal process harder and the risk of addiction, dependence, and overdose that much stronger.

Short-Term Brain Changes

Short-term effects from drugs will vary depending on what type of drug is being used, as well as the dosage (whether it’s a stimulant, depressant, or hallucinogen). At a big-picture level, short-term use of drugs will alter one’s mood, perception, energy level, ability to sleep or not, coordination and focus, and ability to function normally. Those on drugs may seem disoriented, out of this reality, and may seem either extremely energized or very drowsy. The come-down effects could include fatigue, headaches, depression, anxiety, or feeling cravings to re-up the drug.

The Basics of Normal Brain Functioning

Our brains are like an electric field of activity, communicating signs throughout various organs, processes, and movements in the body. Neurotransmitters are the chemical messengers that shuttle information between brain cells (neurons) across synapses. These exchanges within circuits of interconnected neurons bring about our thoughts, movements, emotions, and sensations. Each neurotransmitter has a specific role, such as GABA which decreases the firing rate of those neurons, which accounts for our sleep, mood, and relaxation. Dopamine handles reward, motivation, and movement, and serotonin regulates our mood, appetite, and sleep. Groups of interconnected neurons form circuits that handle specific functions.

How Drugs Interact with Normal Brain Function

Most drugs work by either mimicking or blocking the action of neurotransmitters. For example, many stimulants increase dopamine activity, which results in feeling more alert or focused. Alternatively, some antidepressants increase serotonin levels, improving mood. By either enhancing or blocking normal neurotransmitter activity, individuals can feel changes in their mood, cognition, behavior, and even movement. Certain drugs can be helpful to correct imbalances in the brain, but with abuse or misuse, many drugs can disrupt these normal communication pathways, leading to negative consequences.

How Different Types of Drugs Affect Your Brain

Each type of drug will affect your brain differently. Let’s go over the main classification of drug’s effects.

Stimulants

Drugs that increase energy in the body, like caffeine or amphetamines, activate the activity of specific neurotransmitters like dopamine and norephedrine. This generally enhances focus, alertness, energy, heart rate, and mood. Stimulants also increase heart rate, breathing rate, and blood pressure.

Depressants

Depressants, on the other hand, have the opposite effect of stimulants. Examples include alcohol and opioids, and they promote feelings of relaxation, calmness, drowsiness, and reduced anxiety. Some people also use them for sleep. Depressants work by increasing GABA neurotransmitter activity in the brain, which leads to a calming effect. They may interfere with other neurotransmitters in the brain, such as dopamine and serotonin, affecting mood and the reward center of the brain.

Hallucinogens

Hallucinogenic drugs, also known as psychedelics, can create distorted perceptions, visions, and enhanced colors and even hallucinations. People who take hallucinogens often see things that aren’t there and enter altered states of consciousness. Examples include LSD, mescaline, or psilocybin. Hallucinogens work by interacting with serotonin receptors in various brain regions, including those involved with perception, mood, and thought. This disrupts the normal processing of information, leading to altered states of consciousness.

Cocaine

A popular stimulant that’s highly addictive, cocaine blocks the reuptake of dopamine, producing a short-lived and intense feeling of euphoria, energy, and increased alertness. It can also cause anxiety, paranoia, and restlessness, with an inability to calm down and sleep. This drug creates a flood of dopamine in the brain, and when taken over time, can reduce the brain’s natural ability to create dopamine, which is why people become addicted to replenishing the feeling.

Heroin

Classified as a depressant, heroin is an opioid that converts to morphine in the body, which binds to mu-opioid receptors in the brain’s reward system. This creates a powerful rush of euphoria, relaxation, and pleasure. It can cause drowsiness, constipation, and even respiratory depression. Heroin is highly addictive and has a high likelihood of overdose when used frequently. The opioid activation in the brain creates a powerful reward signal, leading to cravings and dependence on the drug. It also disrupts other neurotransmitters, such as pain perception, breathing, and mood regulation.

Methamphetamine

A stimulant, methamphetamine, is a highly addictive drug that increases the release and blocks the reuptake of dopamine and norepinephrine, creating a feeling of strong euphoria, focus, and alertness in the body with increased energy. As with other stimulants, meth can also cause jitteriness, restlessness, anxiety, paranoia, heart problems, or even psychosis. The surge of dopamine and norepinephrine creates pleasure, alertness, and focus and disrupts the natural reward system, which can lead to damage of dopamine neurons and impair cognitive function.

Alcohol

A popular depressant, alcohol primarily affects the neurotransmitter GABA in the brain, and produces feelings of relaxation, a release of inhibitions, impaired judgements and, when consumed in a great amount, causes slurred speech, loss of coordination, and even blackouts. Not only does alcohol affect the brain, it negatively impairs the liver, kidneys, and other organs. Alcohol enhances GABA in the brain, which creates more relaxation and feelings of pleasure, but it also disrupts communication across brain regions, which can affect balance and coordination, judgment, and memory. Chronic alcohol use can damage brain cells and even shrink brain volume.

Marijuana

Also known as pot, weed, or Mary J, marijuana’s psychoactive component, THC, interacts with the brain’s endocannabinoid system, which influences mood, pain perception, memory, and movement. Creating relaxation, euphoria, increased appetite and altered sensory perception, marijuana can also impair cognitive functioning, such as memory, coordination, and learning. THC binds to cannabinoid receptors, and depending on the dose as well as individual brain chemistry, can affect the brain and brain development, especially in young adults or adolescents.

LSD

A popular hallucinogen, LSD (Lysergic acid diethylamide), most popularly known as acid, disrupts the normal functioning of serotonin. It can cause intense and unexpected hallucinations, visions, and altered states of consciousness where individuals under the influence may feel disassociated from normal time and space reality. LSD interacts with serotonin receptors in various brain regions, leading to distortions in perception, mood, and thought. Long-term effects on the brain are still being studied.

The Roles of Age and Sex

Every body reacts to every drug differently, and this holds especially true for those who are very young, old, or by sex assigned at birth.

Adolescents and Teens

Elderly

As the body ages, the brain naturally undergoes changes in blood flow and metabolism, which can impact how drugs work and how they’re processed and eliminated from the body. Older adults typically have increased sensitivity to the potency of drugs, and may feel a stronger effect from a lower dosage. Drugs can also create issues of interactions with other prescription medications: the side-effects can be worse (like increasing the chance of falling or hurting themselves), and they may form a greater dependency.

Sex

Because men and women have different hormonal makeups, they will experience different effects from drugs, especially when it comes to dosage. Their pain perception may be different, where women may feel stronger (and sometimes more negative effects) from opioids compared to men.

Some drugs also demonstrate a higher propensity to become addicted depending on your sex, and the reasons for this depend on the type of drug (stimulant, hallucinogen, or depressant), as well as individual health concerns, brain differences and hormonal structures.

Those who are pregnant, breastfeeding or with underlying mental health issues should especially avoid or be extremely careful under a doctor’s supervision when it comes to drug use, as this can create damage on both a physical and mental level.

Addiction

Brain imaging technology has demonstrated that addiction is a brain disease by delineating profound disruptions in the specific brain circuits affected by addiction. Repeated drug exposure “resets” these circuits toward compulsive behavior so that a person’s control over the desire to seek and use drugs is compromised, despite devastating consequences.

Exploring Imaging Technologies and the Future of Drug Research

When looking at how drugs affect the brain, researchers must go beyond just studying symptoms. New brain imaging technologies and other emerging tech can help researchers study how drugs affect the inner workings of the brain, where they can measure brain activity and function. This may include measuring brain blood flow, or indicating areas of increased or decreased activity. Positron Emission Tomography (PET) is a radioactive tracer that is injected into the brain that scans high concentrations of specific molecules in the brain that measure specific brain functions or neurotransmitter activity. In time, drug researchers hope to track drug cravings, addictions, and monitor the efficacy of certain treatments. AI, Magnetoencephalography (MEG), Magnetic Resonance Spectroscopy (MRS), and Pharmacological MRIs are all new and emerging technologies being studied and used to better analyze the brain and how drugs affect it.

How Caron Can Help Combat Drug Addiction

Caron provides evidence-based, specialized addiction treatment programs for drug abuse through signature and core programming with respect and compassion. We treat people with drug addictions, as well as those with cross-addictions to other substances or process addictions. At Caron Treatment Centers, we believe in Real Results. Real Care. We are Real About Recovery. If you’re ready to get help, contact us online or call 1-855-445-5693.

Sources: NIDA, NIDA Teens, NIH, NCBI