Delirium tremens is the most severe form of alcohol withdrawal

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.

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.

Drug tolerance and withdrawals are consequences of overloading dopamine circuits

Addictive substances or behaviors will typically flood our brains with more dopamine than usual. In response to the overstimulation, our brains will decrease the number of available dopamine receptors. This results in the need for more stimulus for the same response (tolerance) and a rise in negative feelings when the stimulus is absent (withdrawal).

How seizures (potentially) alter consciousness

Seizures occur when intense electrical activity floods the brain, prompting significant loss of self-control and a variety of sensory disruptions and hallucinations. Cultures interpret the episodes differently, with many contemporary norms viewing them as negative while others characterize them as intense spiritual occasions. Author Fyodor Dostoyevsky viewed his seizures this way, as well as cultures in Mongolia, some Shamanic indigenous religions, and others.

'1440 Explores,' Episode 2: Why We Drink and What It Does to US

Alcohol is the world's most popular drug—a molecule that can calm or excite and bond communities or tear them apart. We trace alcohol's journey from ancient rituals to modern hangovers, uncover how it shaped civilizations, and dive into the neuroscience of how it affects your brain and body. With insights from leading experts, we ask: Given all that we know, why do humans continue to drink?

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.

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

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.

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.

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

People with a sleep disorder called REM Sleep without Atonia don't experience the temporary paralysis of skeletal muscles that typically occurs during REM sleep—instead, they have vivid dreams that they act out during sleep.

Most cases of West Nile virus are asymptomatic in people

About 1 in 5 infected people develop symptoms from West Nile, including symptoms such as fatigue, head and body aches, and vomiting. But around 1% of patients develop severe complications such as encephalitis or meningitis, which can be life-threatening. Those who are most likely to become severely ill are people over age 60.

Postpartum psychosis is an emergency requiring immediate psychiatric intervention, with symptoms including hallucinations, paranoia, and delusions that may put a baby at risk.

Alcoholics Anonymous leads to increased abstinence compared with other treatments

That's according to a 2020 meta-review of 27 studies. This large analysis found that Alcoholics Anonymous had between 22 and 37 percent abstinence numbers as compared to other treatments that had figures of about 15 to 25 percent. AA was founded in 1935, in Ohio, and depends on peer connections and consistent meeting availability. (Some users may experience a paywall.)

Vertigo can last for minutes—or months—and may occur periodically

Vertigo can be caused by a variety of conditions, including as a side effect of medication, but if it comes on suddenly and is accompanied by other symptoms including difficulty with speech or weakness on one side of the body it's important to go to the emergency room to get checked for a stroke. For recurring vertigo, care teams can teach patients exercises to limit panic, lessen nausea and teach the brain to better tolerate head movements.

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.

Alcohol may be responsible for about 5% of cancer cases and 4% of cancer deaths in the US.

American medical organizations rescind recognition of diagnosis cited in police custody deaths

American medical organizations have rescinded their recognition of a syndrome whose theory stemmed from discredited research. This article explores the history and implications of "excited delirium syndrome," a medical condition that can reportedly...

Terminal lucidity is the phenomenon of sudden, heightened mental clarity when on the verge of death

The "Let's Talk Near Death" podcast explores phenomena around the end of life, inviting guests to recount their own experiences. This episode focuses on the phenomenon known as "terminal lucidity," where patients experience clarity, vivid memory recall, and more, typically following a heart attack, stroke, or other trauma.

Memory disorders disrupt the brain's ability to make, store, or recall memories

These disorders stem from reversible issues like vitamin deficiencies or irreversible causes such as stroke or dementia. Only one type of dementia—familial Alzheimer’s disease—is directly inherited and accounts for about 20% of Alzheimer’s cases.

Post-treatment Lyme disease syndrome may be caused by bacterial remnants in the liver

PTLDS, which refers to lingering symptoms of Lyme after antibiotic treatment, is an area of active research. Rodent research published in 2025 suggests that these ongoing symptoms may potentially be due to the body's inflammatory response to lingering cellular components from the bacteria that cause Lyme, Borrelia burgdorferi. In rodents, components of the bacteria's cellular wall may remain in the liver after the bacteria were eliminated with antibiotics.

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.

The federal government allowed toxic chemicals into alcohol during Prohibition

Industrial alcohol was still legal during Prohibition, and was often used by bootleggers. In an attempt to disrupt the black market, the government required toxic additives to be included in industrial alcohol, leading to more than one death.

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.

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.

Dementia describes progressive memory issues that impact daily activities

Although Alzheimer's disease is sometimes thought of synonymously with dementia, there are multiple types of dementia, which manifest in memory loss and other symptoms that make it challenging to perform daily tasks. These types include Lewy Body dementia, vascular dementia, and frontotemporal dementia. Parkinson's disease is not a form of dementia, but this movement disorder can sometimes develop into issues with memory and a formal diagnosis of dementia.

Central vestibular disease is another common cause of vertigo

Unlike peripheral vestibular disease that is caused by factors like inflammation in the inner ear, central vestibular disease involves dysfunction of one or more parts of the central nervous system. Vertigo of this type may last for seconds, hours, or even days. It's typically caused by issues with the brain stem and cerebellum and could be caused by stroke, tumor, and vestibular migraine, among other conditions.

Neurodegeneration is the process underlying dementia, but it may happen for myriad reasons, and its triggers are under investigation.

Alzheimer's disease is the leading cause of dementia and risks rise after age 65

Read this primer about Alzheimer's disease and learn what factors increase the risk of this form of dementia, including genetics, being a woman, and health conditions, including high blood pressure.

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.

Long-term memory issues among West Nile survivors may be from the body's immune response, not the viral infection.

Bipolar disorder, which is characterized by extreme mood swings, affects nearly 3% of the US population

There are two types of this disorder. Bipolar 1 features a significant manic episode—abnormally elevated mood and frantic energy—followed by repeated depression, while Bipolar 2 vacillates between depressive episodes and hypomania, a milder form of mania, but not a full mania. Listen to this podcast as experts explain the condition.

Left versus right brain strokes vary significantly in long-term effects

Due to the high complexity of the brain, the aftereffects of a stroke can have widely different manifestations, ranging from minor temporary impairments to rapid death. Whether a stroke results in paralysis, speech impairments, loss of bodily function, or death will depend on whether it occurs in the left or right hemispheres or the brain stem.

Traumatic brain injury is a leading cause of brain death—and TBIs are trending up

Traumatic brain injury-related deaths have generally increased between 2000 and 2023, growing from roughly 49,000 to more than 68,000 in 2023. Firearm-related suicide is the most common cause of TBI-related deaths in the US, according to the Centers for Disease Control and Prevention. People also experience TBIs from falls, motor vehicle crashes, or assaults.

Why vascular dementia develops

This type of dementia, the second most common form after Alzheimer's, develops due to microscopic bleeds and blood vessel blockages in the brain. The condition isn't curable but medications to help with blood clotting and high blood pressure are part of a suite of interventions designed to minimize damage to the brain.

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.

Schizophrenia symptoms often appear suddenly

Schizophrenia is a particularly shocking mental illness because its symptoms may appear seemingly without any prior signs of illness after a person has had no symptoms for the first couple of decades of their life. Among teens, symptoms may look like typical adolescent behaviors—withdrawal, being irritable, and having trouble sleeping.

Ménière's disease is a long-term, inner ear disorder that causes vertigo

This severe vertigo-causing disorder may involve long and recurrent episodes of vertigo. Symptoms of this disease include balance issues and hearing loss, tinnitus, and a feeling of fullness in the ear. It typically affects only one ear and is linked to a buildup of excess fluid in the inner ear.

How Alzheimer's disease becomes fatal

Despite more than 100,000 people with Alzheimer's dying each year, the specific cause of death is not the disease itself. Often, secondary diseases arise from complications with the disease, including pneumonia, severe falls, malnutrition, or infection. Read more about the range of complications caused by Alzheimer's here.

Untreated malaria can lead to blocked blood vessels in the brain, coma, and organ failure.

Rabies is nearly 100% fatal once symptoms appear

Rabies, a viral disease attacking the central nervous system, is nearly always fatal once symptoms appear. It spreads through the infected animal saliva (typically through bites) and causes encephalitis, leading to severe neurological symptoms and death. See how the lyssavirus—the bugs behind rabies—work once inside the body.

'Blackout challenge' can cause brain damage or death in under 5 minutes

A social media trend that encourages viewers to asphyxiate themselves until they lose consciousness in the hopes of feeling "high" or euphoric has garnered the interest of teens and adolescents, with dangerous results. Variations of this deadly challenge have been adolescent trends every few years.

Heat exhaustion is the most likely diagnosis if someone is talking clearly

Heatstroke, true to its name, looks more like a stroke. Its symptoms include severe disorientation, irritability, and seizures, among others. A patient does not need to have collapsed in order to have exertional heatstroke, but if someone is talking clearly, they likely have heat exhaustion, and it hasn't progressed to heatstroke.

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.

Emerging research suggests that cannabis, used by about 9% of American adults as a sleep aid, may suppress rapid eye movement and lead to worse quality sleep and fewer remembered dreams.

There's no cure for West Nile virus—and infection can leave patients with permanent symptoms.

Delta brain waves happen during deep sleep, while REM cycles resemble being awake

As the brain cycles from wakeful rest to deep sleep, different brain waves emerge. Alpha waves occur during restful waking states, while theta waves can be associated with light sleep and meditation. Delta waves are observed during deep sleep—but REM cycles more closely resemble active awake states.

Sleepwalking, or somnambulism, is a bit of a misnomer since many things can occur during this state, including speaking, using the bathroom, and more.

Veterans reported single dose of ibogaine improved TBI, PTSD, anxiety, and depression

Research published in 2024 on the Central African plant-derived drug included 30 male combat vets who received ibogaine treatment in Mexico. It reported significant reductions in multiple mental health conditions and no serious side effects. Other work, however, has shown the substance can cause fatal cardiac arrhythmias, killing at least 19 people between 1990 and 2008. (Some users may encounter a paywall.)

How frontotemporal dementia changes your personality

Significant changes in personality later in life are often attributed to psychological factors. But Dr. Bruce Miller, long-time researcher of FTD, argues this shift is most often attributable to changes in the brain.