Explaining the physical connection between the gut and brain

Bacteria in our intestine influence the brain via the gut-brain axis

The gut-brain axis refers to the physical connection between the central nervous system and the digestive tract. Signaling molecules and hormones produced in the gut directly affect brain functions via this internal highway.

Listen to how the gut microbiome influences your emotions

The gut-microbiome connection may involve the enteric nervous system, a collection of hundreds of millions of neurons throughout the gut that transmit signals up the vagus nerve to the brain.

The gut microbiome, explained

This video from 1440 takes a high-level look at what populates the gut microbiome, its purpose, how it affects our health, and much more.

How to maintain a healthy gut

Approximately 40 trillion microbes reside in the human gut, forming a unique microbiome, containing hundreds of millions of neurons in what is often called a "mini-brain". A healthy gut is characterized by an effective mucus-lined barrier that prevents unwanted substances from entering the bloodstream. So how do you attain such an ideal gut? This guide outlines a healthy approach to protecting your gut.

Visualize the different parts of the digestive tract

The digestive tract, also known as the gastrointestinal tract, runs from our mouths to rear ends. Its major components include the esphoagus, stomach, intestines, colon, and more.

A beginner’s guide to the brain

Small but powerful, the brain constitutes only about 2 percent of the human body. However, it runs jus about everything, day and night, all year round. Learn about the different parts of the human brain, as well as its unique defenses, like the blood brain barrier in this four-minute video.

Watch what depression does to the brain

This video explores the neurobiology of depression and why unraveling the complexities of this disease and its etiology will potentially improve treatments. Effective depression treatment, as this video highlights, can eventually make a depressed brain look like a healthy one on brain scans.

How brain cells carry information

At any moment, there is an electrical storm coursing through your body. Discover how chemical reactions create an electric current that drives our responses to everything from hot pans to a mother’s caress.

What’s with the teen brain, anyway

In this video NIDA explores the intriguing similarities between the processes of brain development and computer programming. This analogy helps us understand why toxic environmental factors like drugs, bullying, or lack of sleep strongly affect a teenager’s life The information provided by this video can empower your children or students with information they need make better decisions.

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.

Vitamin B1 is linked to gut motility—helping fight constipation—in 2026 research

A study published in early 2026 found a link between vitamin B1 and the successful movement of food through your GI tract, known as gut motility. The work incorporated genetic and survey data about poop frequency to identify genes associated with gut motility and then separately linked poop frequency data with how much vitamin B1 people ingested, theorizing that the vitamin supports the production of acetylcholine, a neurotransmitter that stimulates GI system contractions.

How science explains déjà vu

Take a fun look at the science explaining the odd experience of déjà vu, which some theories suggest is actually a sign of a healthy brain.

A doctor answers the internet's burning questions about the gut

Gastroenterologist Dr. Ugo Iroku answers the internet’s burning questions about digestion and bowel movements. Get the lowdown on what it means when your stuff is super dark, the impact of coffee on evacuating bowels, and much more.

Are the mind and brain the same? An overview of mind-body identity

A major philosophical debate asks whether the mind and the brain are two words for the same thing. Here's a quick overview of that idea.

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.

How the body produces urine

Things seem so simple when nature calls. But, how does the body actually produce the urine we so regularly and thoughtlessly expel? This detailed, comprehensive animation walks viewers through every step with precise illustrations, from the kidney's filters (known as nephrons) to the direct nerve connecting the bladder to the brain. See how the body does it here.

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.

How stress affects every organ in the body

If you are a visual learner, this resource is for you. Not only does this article from the World Economic Forum outline the causes of modern stress along with helpful strategies, but they have created an approachable infographic to show exactly how stress manifests throughout our different bodily systems. Pair this visual guide with our other resources to gain a deep knowledge of stress and the human body.

Taste buds are found throughout the body, with different biological functions

As biological structures, taste receptors take in molecules, analyze them, and send signals to the brain letting us know what they've found. This functionality makes them useful throughout the body, most notably in the gut where receptors act as glucose sensors.

What is the brain up to when the mind wanders?

As you stare into the distance while washing your home's seemingly never-ending pile of dishes, the brain activates its default mode network. This collection of "task-negative" brain regions associated with memory, reward, action consideration, and prediction alight with activity when humans mentally turn inward, possibly giving rise to the brain's ability to wander and humans' ability to construct internal narratives about the world.

Scientists seeking gut insights are attaching flatulence sensors to volunteers' underwear

This fart-tracking device detects gas generated in the gut, providing insights about gut microbial activity. The underwear sensors measure a component of what is technically called flatus—digestive system gas.

We hear because soundwaves are converted into electrochemical signals in our ears

This science teacher video systematically walks through the biology of the outer, middle, and inner ear. The explanation starts with the auricle, an external part that funnels sound through the auditory canal, and the tympanic membrane (the ear drum), which vibrates when sounds hit it. Beyond that, as the video details, is the eustachian tube, which is connected to the back of our throats and allows air to pass in and out to equalize ear pressure.

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

Goose bumps require a surprisingly complex series of steps

Watch an anatomical breakdown of how goose bumps work—featuring real skin from a human cadaver, a segmented brain, and a detailed anatomical model of the skin—to learn about all the jargon behind goose bump science. (Warning: Includes graphic footage of cadaver skin.)

Exploring the link between history, art, and anatomy

Throughout centuries, art has played a vital role in sharing—and furthering—scientific understanding. This largely began in 1543 when physician Andreas Vesalius worked with an artist and engraver to transform learnings from his dissections into...

How trees transport water from roots to leaves

Trees move water to their extremities via a deft system starting from the roots to the leaves. See how it works in this short video breaking down the process in a Douglas fir.

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

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

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.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Watch how viruses like Ebola can spill over from animals to humans—and vice-versa.

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

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

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

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

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

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.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

Watch this video that uses Lego bricks to explain how venture capital works.

Dorothy's famous entrance into Oz in 'The Wizard of Oz' relied on analog tricks, including a body double and sepia-toned paint, as much as it did on technology

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

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.

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

Quincy Jones' 'Big Band Bossa Nova' helped introduce bossa nova—a jazz-influenced Brazilian genre—to the US