1440: Everything you need to know about Alzheimer's

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.

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.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Visualize the difference between a healthy brain and one with Alzheimer's

The brain has three main parts—the cerebrum, brain stem, and cerebellum—each combining to control the entirety of the body's operations. Alzheimer's progressively deteriorates the circuitry in these structures, resulting in what we see as the symptoms of the disease.

An Alzheimer's patient discusses her condition with children

Alzheimer's is a deadly disease that profoundly changes a person's abilities and personality, which makes it difficult to explain to kids. Responding to potentially uncomfortable questions with honesty (and relatable imagery) about the costs and nature of the disease goes a long way in fostering understanding.

"Plaques" and "tangles" are top potential causes of Alzheimer's—but questions remain

The exact causes of Alzheimer's—and how to treat it—continue to be the subject of intense research. Two leading factors are amyloid beta plaques and tau protein tangles, which effectively pile up in the brain and interfere with neurons and cause cell death, which manifests as memory loss and other symptoms.

Five to ten percent of Alzheimer's cases are early-onset

Early-onset Alzheimer’s typically emerges around 40 to 50 years of age, with devastating effects. This video follows Brian, diagnosed with the disease at age 54, as he travels the country as an advocate for research and discusses the progressive mental fog of Alzheimer’s.

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.

Learn the differences between mild cognitive impairment and age-associated memory loss

Mild cognitive impairment is a condition in which people experience more thinking and memory problems than expected for their age. It's often associated with depression and anxiety. Daily routines, writing things down, and healthy lifestyle choices can help cope with the condition, but there's no cure. The condition elevates the risk of developing dementia and Alzheimer's.

How neurodegeneration happens, the underlying disease process of dementia

Dementia symptoms may vary between individuals, and may include mood changes, difficulty walking, speaking, and memory problems. It can progress over many years, occurring due to progressive damage to nerve cells in the brain. This degradation may happen for myriad reasons, and its triggers are under investigation.

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.

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.

Read the original 1907 paper on the first known Alzheimer's patient

Alzheimer's disease was first identified by Dr. Alois Alzheimer in 1901, following a postmortem brain examination of a patient experiencing memory loss and other symptoms. Alzheimer's original paper was largely lost until 1995, when an English translation was published in a medical journal.

There are two FDA-approved blood tests that may detect early Alzheimer's disease

Yet the tests are only recommended for those who have symptoms of dementia, and are not definitive on their own. False positives are a concern with these new tests, which detect biomarkers that may indicate the presence of brain proteins linked to the disease. This podcast explores the state of research on the disease and concerns about regulators taking jobs at pharmaceutical and biotech companies, which may influence their approach to approvals. It also dives into an investigation about the data underpinning one experimental Alzheimer's drug.

A first-person account of receiving an Alzheimer's diagnosis

Having Alzheimer's is a bit like having a part of your brain sliced away each day, according to author Greg O'Brien. This 34-minute podcast episode introduces O'Brien and his co-host, author David Shenk, as the two embark on a multi-season conversation on Alzheimer's disease and O'Brien's diagnosis.

Some dementia cases may be linked to microorganisms in the brain

Researchers now know that, much like the gut, the brain is home to an ecosystem of microorganisms—the brain microbiome. While this area of study is still new, some scientists believe 50% of bacteria-caused dementia cases could be treated. (Some users may encounter a paywall.)

After a dementia diagnosis, it's important to plan ahead but also savor the moment

The next steps after a diagnosis include taking lifestyle steps to slow disease progression and completing legal paperwork about long-term medical preferences. It's also important to appreciate the moments and days ahead and find humor in them, when possible. (Some users may encounter a paywall.)

America's financial burden from dementia in 2025 was $781 billion

That figure, calculated by researchers at the University of Southern California, includes medical and long-term care costs, unpaid family and friend caretaking, lost productivity for patients and their families, and the economic loss in quality of life for patients and their families. In 2025, they estimate there were 5.6 million people living with dementia.

Dementia caregiver training programs exist—but they aren't common

Comprehensive dementia care programs go beyond offering support to caregivers. They train people on how to modify their homes, communicate with their loved ones with dementia, and cope with the stress of caregiving, among other skills. Yet despite evidence showing their effectiveness and the economic benefit of avoiding unnecessary emergency room visits, these programs are often poorly funded and difficult to find.

Smell is a robust memory cue for individuals with Alzheimer's disease

Odor is more effective than both visual and verbal cues for triggering autobiographical recall in Alzheimer's disease, according to 2021 research.

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.

Arthritis is an umbrella term for various conditions that cause joint pain

Arthritis isn’t one single disease, but rather a range of conditions that all lead back to the same outcome—joint pain. This American Academy of Orthopaedic Surgeons primer is a go-to resource for understanding what arthritis is, the most common types, and various treatment options depending on the underlying cause.

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.

What's the difference between a psychologist and a psychiatrist?

While both psychiatrists and psychologists are mental health professionals, the big difference is that psychiatrists are medical physicians (MD or DO) while psychologists are not. Learn what makes these two profession different with this brief explainer.

Autism Spectrum Disorder, defined in 2013, was previously categorized as numerous disorders

This exploration of ASD history walks through how autism science and diagnoses have evolved over the decades, including the new category in the DSM-4 in 1994 that created Asperger's disorder and pervasive developmental disorders, and the new, broader ASD definition in 2013 in the DSM-5 that has led to more diagnoses.

Medicare vs. Medicaid explained in 60 seconds

Medicare and Medicaid both provide government-funded healthcare but serve different groups. Medicare, launched in 1965, covers those 65 and over and has three parts: hospital stays (A), outpatient care (B), and prescriptions (D). Medicaid, funded by federal and state governments, supports low-income individuals, with eligibility varying by state.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

Doctors differentiate between a phobia and fear by asking patients whether their fear interferes with their day-to-day activities.

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

Marburg virus, related to Ebola, is also extremely deadly, and has no available vaccine.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

A researcher recently discovered an interview from 1967 between groundbreaking journalist Joan Didion and the Grateful Dead, years before the band became an institution.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

This poison ivy knowledge quiz—accompanied by photos of the plant's varied forms—may help you identify this common rash-inducing growth.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

Walt Disney's early film 'Alice's Wonderland' was a groundbreaking innovation in the silent film era

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

Learn how to read a prospectus, the juicy document that any company must file with the SEC before going public.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

The Mona Lisa's celebrity status and repeated restorations have obscured what made the painting so revolutionary for its time

The first steps to rebuilding your credit score include getting to know exactly what's on your credit report and figuring out how far you are from the '700 club,' or 'good score' range.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

Trace how the Bill of Rights, inspired by centuries of political theory, took shape between 1774 and 1789.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Use this calculator to find the dollar value of your mental load, from meal planning to coordinating after-school care for your children.