How brain cells carry information

Neurons send signals through electrical impulses and chemical messengers

By converting electrical signals into chemical messages at synapses, neurons allow information to travel throughout the nervous system. With repeated use, synapses grow stronger, enhancing the associations between neurons.

How neurons give rise to thoughts

Neurons in the brain are singular nerve cells that flicker on and off or connect to each other based on incoming stimuli. The more neurons communicate by firing electrical impulses through tendrils known as synapses, the stronger their connection becomes. The electrical energy zipping along these interneural connections in an attempt to classify and respond to incoming stimuli may be what gives rise to thoughts.

Explore an interactive 3D model of the brain

The brain contains about 86 billion neurons—nervous system cells—and controls vital bodily functions via electrochemical signals. Neurons form circuits through axons, and different brain regions use these circuits to perform specific tasks.

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.

Complex molecular reactions in our tissues cause muscle contraction

When we want to move a muscle, a signal travels from the brain and into the muscle cells in question, sparking a chemical reaction that causes the muscle's smallest contractile units—sarcomeres—to shorten, forcing the muscle to contract.

Explaining the physical connection between the gut and brain

This video overview from Duke University helps visualize the gut-brain axis—a physical connection of nerves running from the brain to digestive tract that acts as a physical and chemical link.

Explore how cells respond to signals from their environment

In "Dropping Signals," users can drag stimuli, such as hormones and light, into various cellular environments to observe cellular responses. These include changing their shape, enabling the transport of chemicals into or out of the cell via the cell membrane, or dividing to compensate for surrounding damaged cells.

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.

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

Most advanced touch screens rely on electrical charge in your skin

Capacitive touch screens store electrical charges in an electrostatic grid of tiny wires. When we touch the screen a tiny electrical charge is transferred from the screen to the finger to complete a circuit (since skin has positive and negative charges). This connection creates a voltage drop on that point of the screen. Cloth, however, doesn't conduct electricity, which is why humans can't wear thick gloves and operate their smartphones.

How the five senses share information with each other

The human body depends on information from the five sensory organs—the eyes, ears, nose, tongue, and skin—to react to the world around it. Each of these organs, in its own way, relies on complex circuitry to send signals back to the central nervous system.

Brain activity goes into overdrive around the point of death

Recent studies suggest increased electrical activity in the brain during and after clinical death could be responsible for near-death experiences. Both high-frequency gamma waves (linked to perception and attention) and low-frequency beta waves (related to focus and concentration) increased and became more synchronized across multiple brain regions, potentially resulting in a near-death state of heightened consciousness.

The limbic system drives emotion, memory, and survival instincts in the brain.

This interconnected group of brain structures—including the amygdala, hippocampus, thalamus, and hypothalamus—processes emotional responses, regulates bodily functions, and plays a key role in memory and learning.

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

This NPR video makes clear that there are surprising similarities between how our bodies and fireworks function. Fireworks and our bodies are both packed with carbon atoms, and have controlled releases of energy that create heat—keeping the human body warm or fueling fireworks' heat, respectively. What's more, the human body even emits a tiny bit of light somewhat similar to fireworks—though it's not visible to the human eye.

Scientists have unraveled new details about which nerve cells control goose bumps

Research in 2016 revealed that at least eight different types of neurons are associated with the sympathetic nervous system. One finding revealed that goose bumps and nipple erection are caused by neurons specialized to regulate these specific functions by controlling the erectile muscles in those tissues.

The science of spring fever

Researchers have confirmed what people have sensed for ages: Our emotions during the springtime can go a little wild. This piece breaks down the impact of the seasonal transition on our bodies and prescribes a few ways to mitigate the effects.

While dreaming, the brain connects new information with already-stored memories

During dream sleep, the brain makes connections between new information learned during the day and information already stored in the mind, creating a revised mind-wide web of associations. The dreamer also temporarily becomes confused about time and place and is subjected to a pendulum of strong emotions.

The inner life of a cell

White blood cells are responsible for protecting the human body from infection. This video uses biophysical data from Harvard researchers to accurately demonstrate what goes on inside one white blood cell as it works within the immune system.

Like fingerprints, brain anatomy is unique too

Researchers have discovered that a combination of experiences and genetic factors shape the anatomy of the human brain. They found even quick experiences affect the brain’s genetic makeup, which—over time—means every person develops a completely unique brain anatomy. While brain imaging could be used to identify individuals, it remains much more expensive than fingerprinting for now. Read to found out more about this study from the University of Zurich.

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.

The air around lightning can be five times hotter than the sun's surface

The rapid discharge of electricity—flowing electrons—between oppositely charged regions across a narrow filament can raise temperatures to 30,000 degrees Celsius (54,000 degrees Fahrenheit). If lightning strikes a tree, the speed of the temperature spike can almost immediately turn all its water into pressurized steam, causing it to explode.

A Venus flytrap's hairs convert sensory touch into electrical signals

A stretch-activated ion channel called DmMSL10 acts as an amplifier, converting grazing contact into a strong impulse that the plant uses to react and close its jaw. To distinguish prey from raindrops or other stimuli, the jaw only closes when the hairs are touched twice in quick succession.

Movement of molten metal around its solid inner core creates Earth's magnetic field

According to the geodynamo process, the rotation of the planet and the looping, convective flow of electrically conductive iron and nickel produce dynamic electric currents, which generate a self-sustaining magnetic field. This is unlike natural, stationary magnets, which possess a static field created when the metal cooled and its atoms aligned with Earth's magnetic field.

A dispute about the origin of twitching frog legs led to the invention of the first battery

Experiments by Luigi Galvani on exposed frog leg nerves showed activity when they were hung from iron railings and brass hooks, suggesting the existence of "animal electricity" that discharged when connected to metals. Alessandro Volta's voltaic pile, which stacked metals with an inorganic electrolyte, showed that electricity originates from chemical reactions.

The flow of electricity in AC circuits flips back and forth, unlike DC circuits

Alternating currents in the US change the flow direction 120 times every second, allowing for efficient transformation and transmission of energy across power grids by sending energy at lower currents. This is changed into one-way direct currents when powering electronics.

What a railroad spike through the head taught science about the brain

In 1848, a railroad worker survived an accident that drove a 13-pound iron bar through his head. The injury changed his personality, and our understanding of the brain.

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

Dirty lightning is a thunderstorm created from friction between rising and falling flows of ash and smoke during volcanic eruptions.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

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

Massive blooms of microscopic plankton called dinoflagellates produce the neon blue light seen in glowing tides.

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.

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.

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.

This site reaches millions of visitors who are tired of AI chatbots and seeking human connection. Pretend to be an AI chatbot and ask questions, provide answers, and draw for people in real time.

Ebola infects and disables immune cells, triggering a cascade of events that leads to small blood clots throughout the body, weakening blood vessels and interrupting blood flow to key organs.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

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

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.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

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.

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.

Poison ivy can cause rashes year-round since all parts of the plant contain urushiol, the oil that triggers our allergic response.

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.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

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.