Drug tolerance and withdrawals are consequences of overloading dopamine circuits

Addictive drugs can cause dopamine levels to become ten times higher than normal.

Addiction develops when the pleasure circuits in the brain get overwhelmed

Normal pleasure circuits become overwhelmed by addictive substances, triggering dopamine floods many times stronger than those induced by everyday reward experiences. The understanding of addiction as a brain disease has led to treatments pairing medication and counseling.

Addiction is defined as chronic compulsive drug use despite adverse consequences

This resource from the National Institute on Drug Abuse provides a comprehensive look at addiction as a complex brain disorder. It explores why people initially take addictive substances and how continued use alters the brain’s reward system.

Chronic drug use can cause neurological changes in the brain

Neuroscientist Judy Grisel breaks down the biology of addiction, examining how drugs hijack the brain’s natural reward system and create lasting neural changes. The physiological and neurological impacts of chronic drug use require a multifaceted treatment approach.

Fame can trigger addictive, drug-like highs in the brain

Differences in the type of fame, such as movie stardom, sports, and internet virality, can produce varying degrees of dependence on individuals based on their age and background. Some individuals—particularly children—can develop drug-seeking behavior as they pursue continuous dopamine spikes if they lack an existing sense of fulfillment from elsewhere.

Why the human brain loves opioids

When opioids enter the brain, they dock in receptors, blocking electrical pulses such as those that communicate pain. They also trigger the release of dopamine, a neurotransmitter tied to motivation and associated with stress relief.

Coffee is addictive, and those going through withdrawal often experience headaches and fatigue.

A major dopamine hit from social media use comes from unpredictability—not knowing if the content users post or share will get the 'like' from other users, triggering cycles of anticipation similar to those experienced with a slot machine.

Overuse of opioids can lead to hypersensitivity to pain.

Can the gut microbiome drive addiction?

New research suggests an imbalance of gut microorganisms may influence the likelihood of addiction and addictive behaviors by increasing the severity of withdrawal symptoms, triggering brain inflammation in regions of impulse control, and more.

The body produces its own opioids that act on several receptor types throughout the body, triggering the release of dopamine and suppression of noradrenaline, neurotransmitters associated with reward and alertness, respectively.

Opioids mimic naturally produced endorphins to dull pain.

Some people may be genetically predisposed to loving roller coasters

Recent studies indicate that individuals with higher levels of dopamine may be more prone to thrill-seeking behaviours like riding roller coasters or even doing drugs or shoplifting.

Trauma is a primary risk factor for substance use disorder later in life

Studies indicate 75% of people with substance use disorder have experienced at least one traumatic experience in their life. These experiences alter brain function, leading to heightened stress and emotional pain. Substances offer temporary relief, but this often results in dependency.

DBS effectiveness in treating addiction remains uncertain amid inconsistent results

Critics argue that deep brain stimulation should be considered a last resort and not a scalable solution, given its high costs and trials limited to small samples. However, it has helped some patients manage severe opioid use disorder when conventional methods didn’t work.

The science of addiction treatment

A helpful resource from the National Institute on Drug Abuse (part of the NIH). This article examines addiction treatment and recovery through the science behind several accepted methods. The guide draws helpful comparisons with other chronic disease treatments. In particular, it discusses the overlap between medications and therapeutic treatments, and the understanding that relapse doesn’t indicate treatment failure—only a need for continued or modified care.

Methadone binds to the same receptors as heroin and other opioids

Methadone is a long-acting opioid agonist that works by binding to the same brain receptors as other opioids (like heroin or morphine), but without producing intense euphoria. It reduces withdrawal symptoms and cravings, helping people stabilize and avoid illicit opioid use.

What exactly is dopamine?

Dopamine is a neurotransmitter—a chemical released by neurons that enables neural communication—that makes people want things with an "almost animalistic desire," compelling them to snack or check phone notifications. Often misrepresented as a "pleasure" chemical, dopamine is involved in motivation, learning, attention, habit formation, and more. Trends like dopamine fasting overinflate its role in mental health and often use it as part of "straw man" biohacking claims.

'Susan's Brain': what happens to the brain during addiction

This engaging animation from Harvard Online breaks down the neuroscience of addiction through the story of “Susan’s brain,” demonstrating how addictive substances hijack normal reward pathways. Through clear visual metaphors and approachable narration, it explains complex brain chemistry in understandable terms.

Prolonged stress impairs the prefrontal cortex

Burnout isn't just a feeling—it physically affects the brain. Prolonged stress impairs regions of the brain responsible for decision-making, emotional control, memory, and more. It can also lead to chemical imbalances, like reduced dopamine and norepinephrine levels, that worsen these effects.

Love and heartbreak trigger powerful, neurochemical-driven changes in the body

The feeling of falling in love floods the brain with dopamine, oxytocin and serotonin, which collectively dull pain and boost immunity. However, the loss of these chemicals during a break-up produces withdrawal-like symptoms and heart issues, such as high blood pressure.

Delirium tremens is the most severe form of alcohol withdrawal

Due to the impact of alcohol on the central nervous system, withdrawal from the drug can cause severe effects. Roughly 1% to 1.5% of heavy drinkers will experience delirium tremens, which includes tremors, seizures, hallucinations, and more. Onset typically occurs 48-72 hours after the last drink.

Fantasy sports can have adverse health effects

Experts warn that fantasy sports, including fantasy football, can encourage obsessive use because they offer hits of dopamine. Daily fantasy games, which function more like gambling, are especially problematic.

What happens to your brain when you burn out?

You've probably heard of burnout, also known as the feeling of exhaustion that happens after a long period of being overwhelmed or stressed. It's often associated with work and careers, but other parts of life, like parenting, can cause burnout, too. Scientists are figuring out what happens, biochemically speaking, in the brain when burnout hits—and spoiler alert, it includes a neurotransmitter called glutamate. Watch this video to learn more.

Social media addiction, though not a clinical diagnosis, refers to the idea that infinite scroll, notifications, and algorithms override one's ability to stop using them.

Exercise releases chemicals that enhance cognitive function

Neurotransmitters like dopamine, serotonin, and norepinephrine, along with increased brain-derived neurotrophic factor levels, enhance a wide range of brain functions. New research demonstrates a direct link between movement and numerous cognitive benefits, including memory, learning, and stress resilience.

'Why'd I take speed for twenty years?': an exploration of stimulant ADHD medication

Many people with ADHD are prescribed stimulant medication to assist with symptoms ranging from time blindness to executive dysfunction. This hour-long podcast episode by Search Engine explores the host's experience with ADHD medication and the history of amphetamine and methylphenidate use in the US.

Naltrexone blocks the reward effects of alcohol and opioids

Naltrexone is used to treat alcohol and opioid dependence, blocking opioid receptors in the brain, reducing cravings, and preventing the euphoric effects of alcohol or opioids. It is nonaddictive and works best as part of a comprehensive treatment plan, including counseling or therapy, to support long-term recovery.

This is the human brain on the world's strongest psychedelic

Within seconds of inhaling a high dose of vaporized synthetic 5-MeO-DMT—a lab-produced substance that otherwise is naturally derived from the glands of the Colorado River toad—it induced slow brain waves. Such waves are typically associated with unconsciousness due to a coma or anesthesia, perhaps explaining why users describe feeling like everything falls away. The compound is currently in clinical trials for treating depression.

Clinical burnout: prolonged exhaustion, mental distance, and persistent negative feelings

Burnout isn’t just stress—it’s a pervasive feeling of exhaustion that can start in the workplace and seep into everyday life. It causes feelings of dread and cynicism about work tasks. On top of emotional distress, there can be physical symptoms and a tendency towards addictive behavior.

Opioids are a class of drugs including fentanyl, heroin, oxycodone, and more.

Our phones can provide a dopamine hit because of our positive associations with them, which feeds into what some psychologists call social media addiction.

How alcohol rewires your brain

Alcohol doesn't just make you tipsy—it rewires your brain chemistry in real time. It slows your brain with GABA, spikes dopamine to make you feel unstoppable, and blocks glutamate so you can't form memories. That mix explains everything from slurred speech to blackouts … and brutal hangovers.

GLP-1 drugs are under investigation for treating Alzheimer's, Parkinson's, and drug addiction

Researchers are investigating GLP-1 applications for a variety of chronic conditions. One area of interest stems from how study participants using GLP-1 for diabetes and obesity reported describing less longing for wine and cigarettes while taking the medication—intriguing researchers about using the drugs for addiction applications. The drug, they theorize, could bind to receptors that mediate desire. (Some users may experience a paywall.)

Can you overdose on vitamins?

Many people pop a multivitamin supplement each day thinking that any excess nutrients won't hurt them. This article explains how chronic excess of any vitamin can cause toxic levels in the body. This condition is known as hypervitaminosis, and symptoms vary depending on what vitamins have achieved toxic levels of accumulation. According to this article, dietary supplements in the US are not required to submit to the FDA documentation supporting their efficacy or safety.

Drugs 101: An interactive guide

What's the difference between opioids and psychedelics? This guide details specific drugs and their various associated effects. Drugs in this wheel fall into seven categories: stimulants, depressants, empathogens, psychedelics, dissociatives, cannabinoids, and opioids.

Stress and the brain

While an acute stress response is a normal bodily function, the effects of chronic stress can be extremely damaging to the human body. This is particularly true with regard to the brain. This article explores the effects of stress on the human brain, including how chronic stress may lead to psychological conditions such as depression and memory loss.

How four types of psychedelics affect the brain

Brain imaging shows that ayahuasca, MDMA, DMT, and psilocybin profoundly affect neural activity, giving rise to higher states of introspection and consciousness. This article details exactly how each of these drugs physically affects the brain and what that means for mental health treatment. Some of these drugs quiet the brain or trigger the release of neurochemicals associated with mood regulation and learning.

Psychedelics interact with neurotransmitter systems to alter one's perception

LSD, psilocybin, and MDMA can suppress the brain's default mode network and enhance connectivity. Research shows that, when paired with therapy, psychedelics may help treat mental health conditions, including depression, addiction, and PTSD.

Alcohol use disorder is the most common addiction in the US

This comprehensive overview from the Addiction Center uses recent data from SAMHSA’s National Survey to examine the 10 most common substance dependencies in the United States. It ranks addictions from alcohol (affecting 28.3 million Americans) to barbiturates, while highlighting key trends, risks, and societal impacts.

Why we pay to be scared

Why do we love roller coasters? It’s not just the speed or height, it’s controlled fear. Your brain thinks you’re in danger, then rewards you with dopamine.

How burnout alters your brain

Stress is a normal part of everyday life, and it’s not necessarily all bad. But chronic stress—the kind that leads to burnout—can change the size and functioning of parts of your brain. It can alter the ability to make new brain cells and memories and even potentially modify your DNA.

TikTok's personalized algorithm activates the brain's reward system

A 2025 Washington Post study found that 75% of the TikTok users it studied nearly doubled their time spent on the app within a month. Experts in design and psychiatry say this is due to the app's interface and algorithm, which, after learning about the user's preferences, recommend videos more likely to activate that person's dopamine reward system than non-personalized suggestions.

'The opposite of addiction isn't sobriety—it's human connection'

This thought-provoking TED talk from journalist Johann Hari challenges conventional wisdom about addiction, with a special focus on his global research investigating its root causes. Through personal stories and scientific evidence, Hari debunks some of the most common myths around addiction.

The negative effects of cannabis use

After decades of criminalization, cannabis is a legalized drug in an increasing number of countries around the world. This allows for accurate, robust research on the drug's effects on humans . While weed isn't as harmful as alcohol, regular usage has its negative effects. As strains of the drug become stronger, so does its consequences. Watch this video for a lucid look at the effects of cannabis on its users.

US FDA recently approved the first new schizophrenia drug in decades

Though other antipsychotics block dopamine receptors, a new drug, Cobenfy, influences dopamine levels via a different pathway—it stimulates a pair of specialized receptors in the brain that control the release of a substance called acetylcholine. This alternative approach may help patients avoid serious side effects like weight gain. (Some users may experience a paywall.)

Grief rewires the human brain

The human brain handles stress and emotional traumas similarly. In response to the emotional stress of a situation like the death of a loved one, divorce, or abuse, the brain may strengthen or weaken connections between nerves to form new neural connections. Over time, chronic stress can diminish brainpower, reducing overall nerve growth and memory to shift resources to enable elevated fear responses and enable humans to survive.

How the feared self fuels OCD

Obsessive-compulsive disorder is characterized by intrusive thoughts that prompt people to enact compulsions—behaviors intended to relieve the anxiety or stress from the obsession. A significant intrusive thought OCD sufferers endure is the fear they will become a dangerous or immoral person. Therapeutic approaches try to show patients this is just a story that can be set aside.

Psychedelics set off a flurry of brain activity that may permanently alter it

The brain seems to experience a sharp increase in communication between areas that generally don't interact. New research suggests a thin, sheet-like gray matter structure tucked deep within the brain, between the insular cortex and striatum, may be the key to this change. The area is centrally located and home to many of the receptors that psychedelics target, potentially rewiring the brain and rewriting thought patterns.

These areas of the brain are hard-hit in depression—but the changes are reversible

Depressed brains can have certain characteristic changes, including an overactive amygdala, reduced hippocampus size, and changes to the thalamus and neuromodulating chemicals in the brain.