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

Scent is a stronger memory trigger than sight

Smell is imbued with more emotion than visual memories, and research indicates that smell triggers a significantly greater effect on amygdala activation. Scientists believe these powerful responses occur partly because smell signals bypass the thalamus and go directly to the amygdala and hippocampus, brain areas involved in emotion and memory.

Smell retraining can help people with anosmia learn to smell again

Olfactory training, which involves repeatedly smelling a selection of strong odors, teaches your brain to familiarize itself with experiencing smells over a lengthy period, typically multiple months. This can be useful for patients who lose their sense of smell for myriad reasons.

A super-sniffer smelled her husband's Parkinson's disease years ahead of symptoms

She discovered she could smell diseases, including Parkinson's, tuberculosis, Alzheimer's, cancer, and diabetes. Working with an analytic chemist, she's learned she can smell subtle changes in odor—ones that smell consistent across individuals with the same disorder—even before symptoms manifest.

Read a study documenting how 'old people' smell increases with age

Analysis of body odors from individuals aged 26 to 75 confirmed that 2-nonenal, an unsaturated aldehyde with an unpleasant, greasy, and grassy odor, was detected only in subjects aged 40 and older.

Scientists are reconstructing ancient smells—including a 3,500-year-old ancient Egyptian mummy

Researchers explain how they have recreated the scent of ancient Egyptian mummies and enabled museum-goers to experience that scent on specialized cards. The exhibit will be at the Royal BC Museum in Canada in June 2026.

Newborns have a strong sense of smell

Babies are drawn to their mother's smell—and the particular odor of their mother's breast milk—within days, even as their vision remains blurry for months after birth. In the womb, the olfactory center also forms in the early stages of development.

Humans may be able to distinguish more than one trillion scents

That's according to one estimate published in 2014. This figure far exceeds earlier estimates of a human smelling ceiling around 10,000 odors. The newer figure is derived from experiments in which volunteers agreed to sniff varying scents. Researchers mixed odor components and had volunteers sniff the brews to detect subtle scent differences. (Some users may experience a paywall.)

Retrieval cues trigger memories and emotions from long-term storage

Retrieval cues can activate specific cells in a neural network, creating a cascade of neurons that collectively make up a memory. Specific cues help regulate emotions during stress by activating positive memories.

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

Blindfolded people could identify objects by touch alone a week after encountering them

These touch memories are more complex and durable than previously thought. In research published in 2018, blindfolded volunteers touched over 150 household objects for about 10 seconds each, and afterward correctly identified the objects more than 90 percent of the time when presented with the object and a similar one. Participants still knew most of the objects a week later with about 85 percent accuracy. (Some users may experience a paywall.)

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.

How Alzheimer's caregivers get pulled into their loved one's reality

Caregivers, most often children and spouses, do not just witness a family member's cognitive decline—they also often become drawn into it, navigating a world in which the typical rules of time, order, or logical continuity may not apply.

Does our fear of Alzheimer's create stigma around its treatment?

Surveys suggest our fear of Alzheimer's as a disease outranks that of heart disease and cancer. This piece argues our fear of aging and the slipping away of our mental capacities make it more difficult to treat Alzheimer's compassionately.

Sensory memory is information collected from your senses

Lasting seconds before moving into short-term memory or being forgotten, sensory memory aids in environmental awareness and navigation. Key brain regions involved include auditory, somatosensory, gustatory, visual, and olfactory cortices.

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 'fishy' scent does lead to mistrust

In experiments where people were exposed to a literal fishy smell they were less willing to cooperate with others in economic games requiring trust, but that wasn't the case when they were exposed to another bad odor—the smell of flatulence.

Alzheimer's is most prevalent in the South and the East

Risk factors for Alzheimer's can include age, race, education, and income levels, exposure to pollutants, and much more. As of 2023, these factors are seen in higher incidence rates for those above 65, in the southern and southeastern parts of the US.

Nostalgia is a psychological coping mechanism created from bias

Memories are naturally reconstructed during recall, and research has shown a fading effect bias that causes negative ones to fade more quickly, helping us heal. This creates a natural longing for the past, particularly when faced with loneliness, boredom, or challenging moments in the present.

Can music alter your memories?

You’re familiar with music’s ability to transport you to a past experience, but new research suggests that music can even alter how you remember your past experiences. A team of psychology researchers and music experts recently published a study that demonstrates how music can help shift our emotional recollection of a memory. Read to learn more about the study’s findings and how it could influence therapy practices.

Resistance training is linked to better memory and cognitive function in older adults

Randomized control trials looking at structural neuroimaging and exercise suggest that resistance training in older adults induces structural brain changes that could reduce the risk of Alzheimer's Disease or mitigate its progression. The benefits have been documented when performed at least twice per week for at least six months.

Super recognizers may use specific facial features to commit faces to memory

Researchers believe that recognizing individuals seen only in passing, even decades later, is an ability of genetic origin and specific to facial recognition, rather than a result of better overall memory or perception. Applying eye tracking data from super recognizers to AI has led to improvements in facial recognition software.

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.)

Photographic memory isn’t real, but other rare memory types do exist

While 2% of children can recall sensory experiences with extreme detail (eidetic memory) and some adults can remember life events or dates with high accuracy (hyperthymesia), there is no scientific evidence for the flawless recall popularized in fiction. Most memory feats instead rely on training and memorization techniques.

Listen to storytellers explain the legacy of memories shared between children and their mothers

In this podcast, people describe the strength of certain memories, what events stay with them, and when and why grief washes over them. One describes the challenging task of selling her mother's cemetery plots; another, keeping a promise to her son to learn to swim; and in the third, a son discusses the strength of familiar food smells.

The doorway effect is when people forget their task when entering a new space

The "why did I come in here?" feeling after walking into a room comes from the brain creating event boundaries to organize memories. Mentally revisiting a previous room can help recall tasks and reverse memory loss. (Some readers may experience a paywall.)

Neural replays in mice help explain food aversions

Princeton University scientists published research in 2025 analyzing how mice learn to associate certain foods or flavors with feeling ill—even when there’s a time gap between eating something and feeling sick. The work, performed with grape Kool-Aid and injections of a substance that made mice sick, traced the literal “gut reaction” of how gut distress signals are linked to neural replays of what the mouse ate.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

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

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

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

Salvador Dalí believed he was his own dead brother, who had died nine months before he was born

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

The story of Dollree Mapp, whose legal challenge over her 1957 conviction for possessing "obscene material" led to a major strengthening of the Fourth Amendment

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

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.

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

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

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

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

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

Fish populations in the Great Barrier Reef have increased after installing waterproof speakers on the ocean floor that played recordings of sounds from healthy coral reefs.

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.

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives

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.

Some researchers have labeled nomophobia, the fear of being without your phone, as 'the phobia of the 21st century.'

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Many legends about George Washington, including his supposed wooden teeth and the story of cutting down the cherry tree, lack evidence.

Objects can be 3D printed with light by projecting 2D computerized tomography (CT) scans onto rotating cylinders of resin, which solidify upon exposure.