Neurons send signals through electrical impulses and chemical messengers

Explore how excitatory cells, such as neurons and muscle cells, transmit information in the body via electrochemical signals, which can travel up to 120 meters (390 feet) per second.

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.

Take a deep dive into the neuron

Neurons are the basic unit of the brain and nervous system—electrically excitable cells that sends signals throughout the body. They can communicate with each other, fire in sequence, and conspire to do everything from drive body movement to help form memories. Check out this intro-level overview to learn more about their structure and how they work.

Age, stress, and neurological disorders can prevent memory formation and recall

Neurons transmit signals between one another at sites called synapses. Repeated interactions at these sites improve the efficiency of signal transmissions, making memories involving sensory data associated with those neurons easier to recall. Biochemical factors impacting these synaptic interactions affect memory quality.

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.

Synaptic plasticity allows neurons to communicate effectively and form memories

First proposed in 1949, synaptic plasticity allows the brain to adjust communication strength between neurons. This ability to change synaptic strength—either briefly or over long periods—is essential for learning and memory, with long-term synaptic plasticity forming the basis of how memories are stored.

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.

Exercise releases chemicals that enhance cognitive function

Neurotransmitters like dopamine, serotonin, and norepinephrine, along with increased brain-derived neurotrophic factor levels, enhance a wide range of brain functions. New research demonstrates a direct link between movement and numerous cognitive benefits, including memory, learning, and stress resilience.

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.

Memories are formed through attention, repetition, and emotional significance

Our brains create memories by taking in sensory input, filtering it through short-term memory, and storing it in long-term memory. Emotional events are more likely to become vivid, lasting memories because they activate stronger neural connections.

Our sense of smell affects what foods taste like and how we perceive it

Scent stimulates our olfactory sensor neurons high in the nasal cavity, and the brain attaches labels to those scents. But when we eat, chemicals from the foods travel from our mouths and throat to those neurons. We have roughly 400 odor receptors, and they can be used to decipher more than 10,000 different odors (or more than one trillion by some calculations), including the nuances of different foods.

Elon Musk's Neuralink's N1 chip can wirelessly read brain signals from over 2,000 electrodes

The device is a battery-powered brain implant that transmits data via Bluetooth. Neuralink's near-term objectives for the device focus on unlocking new treatments for paralysis, neurological disorders, and some psychiatric conditions.

Electricity is produced when the ends of a battery are connected by a conducting wire, triggering chemical reactions that release the energy stored in chemical bonds.

See how the gut and the brain communicate through a bundle of nerves running from the brain to the digestive tract, serving as both a physical and chemical link.

How aging degrades neural functioning in the brain over time

Aging affects the brain perhaps more than any other organ in the body. Throughout life, the brain experiences radical shifts in the number of neurons, synaptic connections between neurons, and hormone levels that regulate our mood and processing.

Cells translate genetic information into proteins using RNA messengers

Genes are segments of DNA, each composed of a sequence of nitrogenous bases. Within the nucleus, these sequences are copied into a single strand of ribonucleic acid during transcription. This strand leaves the nucleus and is translated by ribosomes into a chain of amino acids that folds into a functional protein.

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.

Transistors are the foundational components of integrated circuits and microchips and manage the processing of electronic signals by controlling the flow of electricity.

Neural networks mimic the structure and behavior of real physical systems

Early generative AI systems were inspired by scientific models such as the Ising model, which explains how atoms interact with one another and align in magnets. As these networks have expanded, their behavior has more closely resembled that of quantum fields, enabling them to be used in exploring complex particle physics interactions.

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.

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.

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.

The body's master clock has 20,000 neurons

The suprachiasmatic nucleus, the master clock in mammals, has 20,000 neurons that help maintain the light-dark cycle in the body. Among its jobs: It receives light input information from the retina and then signals peripheral body clocks to act on this information, driving everything from body temperature to hunger.

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.

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.

Bacteria use chemical signals to communicate and coordinate with one another

Through a system called quorum sensing, bacteria produce and absorb compounds from their environment to identify allies or competitors and adjust their behavior accordingly. Some bacteria produce food-digesting enzymes only in the presence of similar bacteria, thereby preventing competitors from consuming their meal.

What sleep loss does to the brain

Proteins in the brain perform various critical functions, such as helping neurotransmitters function or enabling electrical activity in the organ. These proteins must fold in specific ways to perform their duties, similar to paper airplanes. Sleep deprivation contributes to the gathering of misfolded proteins that aren't shaped correctly for their roles and so accumulate in undesired spaces, such as in the gaps between neurons.

Some animals may speak because of duplicated connections in the brain

Neuroscience suggests that connections responsible for motion made during embryonic brain development—such as those connecting hearing and movement pathways that allow reactive motion when started—are duplicated and connected to the larynx in some animals. This allows some mammals and song-learning birds to speak, provided they have the necessary physiological structures.

Remylination is a huge focus for treatment—especially among older adults

Our ability to build new myelin sheaths for nerves degrades with age. There have been research advances boosting cells that support these processes and clear away debris from degraded myelin, but not yet any medications to boost myelination itself, which would aid nerve signaling and preserve nerve function.

The speed of electricity may refer to the movement of electrons, which is on the order of a fraction of a millimeter per second, or energy, which is near the speed of light.

The first neural devices were cochlear implants, designed to treat hearing loss

Neural interfaces connect with our nervous system to restore or enhance abilities, such as hearing or movement. These neuroprostheses have enabled the restoration of mobility, communication, and activities of daily living that might otherwise require a caregiver.

How chemical bonds between atoms form molecules and large geometric structures

In ionic bonding, one atom transfers at least one electron to another atom, forming two atoms of opposite charge. These atoms attract one another and can stack up in a 3D grid called a lattice. Covalent bonding, where electrons are instead shared, can produce enormous molecules, such as the two found in human chromosome 13, which each contain 37 billion atoms.

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.

A web of sensory neurons in the skin help filter out background sensations

The somatosensory system helps us organize and navigate our surroundings, enabling us to understand our bodies in relation to our environment and also filter out minor sensations that are basically background noise so they aren't overwhelming to our bodies. Meanwhile, viscerosensation—or internal sensation—refers to the internal sensory neuron system that conveys information from internal organs to the brain.

Electrogenic animals generate their own electricity within an electric organ by changing the pattern of electrical charges in disc-shaped cells called electrocytes.

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

Can physics explain where consciousness comes from?

Consciousness is a complex emergent phenomenon of the brain, which is primarily composed of neurons and glial cells. Since all matter is composed of atoms that follow the laws of physics, there may be quantum processes beyond classical electrochemical interactions that can explain where consciousness comes from.

Chronic drug use can cause neurological changes in the brain

Neuroscientist Judy Grisel breaks down the biology of addiction, examining how drugs hijack the brain’s natural reward system and create lasting neural changes. The physiological and neurological impacts of chronic drug use require a multifaceted treatment approach.

The world's first commercial biological computer combines neurons with silicon

Australian start-up Cortical Labs unveiled CL1, a hybrid chip designed to help scientists study brain function in real-time. The 800,000 lab-grown neurons on the chip are kept viable for six months via a built-in life support system.

Meet the 12 cranial nerves

Your cranial nerves are a set of 12 paired nerves in your brain. They help your brain and body communicate senses, movement or both.

Dream interpretation has evolved from ancient mystical explanations, to dream reports, to tracking electrical activity in the brain and more.

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.

With a core consisting of a glass fiber roughly the width of human hair, fiber-optic cables transmit digital information via flashes of light that reflect within the glass.

Explore the biology of pain and why the experience of pain may differ widely from one person to another.

A simple explanation of semiconductors

Semiconductor chips are electronic devices that store and process information. Today they can contain billions of microscopic switches on a chip smaller than a fingernail. The article provides a quick overview of how the devices work and how they've provided the backbone of the computer age.

What are neural networks and why do they matter?

Learn how a neural network works, why it matters, and how it can be trained to recognize patterns, classify data, and forecast future events.

Metabolism, a collection of chemical reactions at the cellular level, processes food and converts it into energy to power the body.

Consistency and emotional engagement can improve the formation of memories

While sleep lets the brain re-trigger neurons associated with our experiences to cement them in long-term memory, repeating actions, like storing one's keys in the same location, can mimic these benefits. Emotionally charged memories are often ruminated upon, improving their future recall.