What rodent cars can tell us about human joy

Rat taxidermy can be a tender, if unsettling, communal activity

At a rat taxidermy class in Chicago, participants use previously deceased rats, usually from lab experiments, as they learn the art of preservation step-by-step. Despite the gore, the act can engender tenderness toward the animal and prompt healthy reflection on death and dignity.

Harvard drowned rats for this?

Harvard's 1950s rat study was ethically questionable, but scientifically profound. One rescue attempt made rats swim 40x longer. The finding: hope isn't poetic, it's biological.

Researchers are studying roller coasters to improve mental health treatments

Scary rides stimulate our fight-or-flight response while simultaneously releasing feel-good endorphins like dopamine, serotonin, and oxytocin. Once we realize we're in a safe space, we can enjoy the ride and even feel confident and relieved by the accomplishment of overcoming a fearful feat.

The reason some people love exercise may be because of their microbiome

Certain gut microbes in mice trigger dopamine release and drive motivation to exercise more. Scientists are investigating whether humans carry similar microbial patterns that influence our natural inclination towards movement, exploring how unseen microbial ecosystems may shape mammalian fitness behavior and reinforce innate reward pathways. (Some users 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.

Mice were able to regenerate retinal cells in the lab—a breakthrough for mammals

Using gene therapy, a team of Korean researchers has enabled retinal regeneration in mice by blocking the intercellular transfer of a single inhibitory protein. This 2025 finding creates a new potential direction for treating retinal diseases. The work, which is still in animal studies, is projected to enter early-stage clinical trials in the next few years.

Brain studies suggest some animals do dream (sort of)

Studies on sleeping cats, rats, fish, and finches show that their brains fire as if performing actions from waking life. Spiders and insects also have REM-like sleep. Whether these findings indicate that animals dream depends on one's definition of dreaming.

Teaching a robot to laugh

Researchers have designed a shared-laughter AI system that responds to human laughter in order to build a sense of empathy into dialogue. Learn how they did it with this explainer.

Visualizing where happiness comes from

Researchers asked 10,000 participants to list 10 things that recently made them happy. One author broke down the responses into subject-verb-object categories, isolating the people and events that made responders satisfied. The result highlights how simple things like having dinner or watching a movie made someone happy. Dive in and look for some ideas or tips on feeling happy today with this fascinating visualization.

Watch a goldfish drive a car

Dutch engineer Thomas de Wolf created a car for a goldfish, or a water tank on wheels that is directed by the movements of the creature inside it. Using a motion-sensing camera, when Blub the fish moves to one side of the tank, the camera moves in the same direction.

How to build curiosity

Change and uncertainty induce stress, but reframing the unknown into an opportunity for discovery has tangible benefits. Approaching change with curiosity enhances activity in the hippocampus and promotes neuroplasticity, promoting learning and serving as a barrier against anxiety. A neuroscientist explains how embracing the unknown, trying small experiments, and other techniques build curiosity.

Rodent evidence is mounting that dysfunctional mitochondria may be a cause of Parkinson's

Though researchers have long observed mitochondrial malfunction in Parkinson's patients, it has remained unclear whether faulty mitochondria cause the disease or are casualties of it. Rodent research published in 2025 adds further weight to the idea that it's causative.

Humans can track smells on the ground quite well—our ability to crawl is a limiting factor

As part of a scientific bet, neurobiology researchers dragged a chocolate bar across the grass and sought to see if a human could track it—she could. This led to a more in-depth experiment on human olfactory capabilities and behavior when other senses were blocked.

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

'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.

Fruit fly experiments show personality emerges, in part, from genetic factors

A 2025 study revealed that fruit flies exhibit unique behavioral preferences, akin to personalities, which could be artificially selected for when breeding to modify behavioral variability. This variability can be adaptive in unpredictable environments.

Is life all about pleasure? Debating the Experience Machine

If you could plug into an Experience Machine that gave you total pleasure all the time, would you do it? Philosopher Robert Nozick thinks you wouldn't, using this as evidence against hedonism, the view that life is all about pleasure. Explore the nuances of the argument and counterarguments with this accessible article.

Wikiracing involves moving between two articles in the fewest clicks

The quirky pastime has evolved into a competitive event at yearly Wikimedia conferences, highlighting the interconnectedness of human knowledge. Neuroscientific research suggests lateral thinking is a crucial skill found in successful Wikiracers.

Neural rhythms shape how we move, focus, remember, and interact with the world

Millions of neurons in the brain produce rhythmic electrical signals, or brain waves, that guide physical movement and help form and store memories. Researchers also use these rhythms to create brain-computer interfaces, letting people control devices using only their thoughts.

What a tiny marine worm can tell us about our brains

Meet the amphioxus, a small eel-like animal that has a lot to teach us about brain evolution. The genetic roots of our brains can be seen in these unusual creatures. This three-minute educational video focuses on the evolutionary history of the human brain through these odd little critters with a 500-million-year-old history.

An anthropologist spent years riding garbage trucks to understand what our trash says about us

Robin Nagle rode with New York City sanitation workers to trace the hidden life of what we throw out. Her research explores what the things we discard reveal about who we are. 1440 explores the hidden life of trash.

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.

California startup Rivian has attracted disillusioned Tesla owners

Some electric vehicle buyers frustrated by Elon Musk's antics have been won over by the adventure-focused company, which has received a $5B investment from the Volkswagen Group to develop crossover and hatchback models with solid-state batteries.

Autonomous vehicles have been confirmed to reduce greenhouse gas emissions

Research indicates that self-driving cars can reduce harmful pollution through lower traffic, decreased parking demand, and optimized driving behavior. These benefits can be enhanced further in smart cities with responsive traffic signals.

How we learn: comparing classical and operant conditioning

Psychology helps us see how we learn, whether through positive reinforcement or by conditioning a response to a stimulus. Learn about these two key theories in this brief video.

Parents and romantic partners naturally touch at speeds optimizing nerve activation

A small observational research study shows that when parents are asked to caress their infants and volunteers are asked to caress their partners, both groups spontaneously stroke their loved ones at velocities that, on average, fell within the optimal range to stimulate the C-tactile afferent nerve receptors. This wasn't the case when volunteers were asked to do the same with an artificial arm, which they stroked much faster.

What pupils can reveal about a person’s thoughts and feelings

Eyes have long been said to be the window to the soul. In this article, a psychologist and pupillometrist explores research demonstrating pupils as a window into the mind. Pupils tell us how intensely someone is exerting mental effort, or even reveal what a person is imagining. Read this article for insight into the field of pupillometry and how it can offer insights into our psyches.

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.

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

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

In recent years a child anxiety expert has created and tested a novel phobia and anxiety treatment approach for children, focused on changing how parents respond to the fears.

A vending machine run with Anthropic's AI went out of business after it was convinced to give away items for free and sell a video game console.

SpongeBob exemplifies Aristotle's philosophy for living well because he understands that happiness doesn't come from external factors like money, recognition, or power.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

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

A Yale student wrote a profound essay about the consulting industry's influence on elite college students that was published in a book of her writing after she died in a post-graduation car accident.

Scientists testing how climate change affects plants found, in a years-long simulation study, that poison ivy grew 70% faster with the resulting extra carbon dioxide.

Mid-century modern graphic designers, known for their bright colors and bold lines in advertising, also found success with children's books.

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.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

The Ramones' 'Pet Sematary,' the theme song for the Stephen King novel of the same name, was written while the band was admiring the writer's collection of horror memorabilia.

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

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

After her fellow cult members tried to kill her with an LSD-infused hamburger, one member of the Manson Family, the murderous cult led by Charles Manson, decided to testify against the group's leader.

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.