How the brain's somatosensory system translates touch into an experience

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.

We can sense touch even through a tool

Research published in 2019 indicates that the same brain regions involved in sensing touch on the body also process it when humans use a tool to do the touching. Essentially, it's acting as a sensory extension of the body. (Some users may experience a paywall.)

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.

How does the body know where it is in space?

Close your eyes and touch your nose. How did you know where your nose was? How could you tell where your hand was? That's proprioception, the sense that keeps your brain apprised of the body's position and movement. This article explains how this sense works, what happens when people don't have it, and what we know about it.

Humans likely cannot tickle themselves because there's no element of surprise

Unraveling the neural mechanisms of tickling—formally called gargalesis—is an area of active research, but a leading theory about why we can't tickle ourselves is that the brain's somatosensory cortex processes self-touch differently than it does external touch. The cerebellum already anticipated what was going to happen when you move your hand for self-touch, limiting the effectiveness of a self-tickle.

How texture affects taste

Texture is the brain's interpretation of several sensations, including pressure, as registered by our teeth, tongue, and finger tips, and sound, as recorded by our ears. Texture also speaks to food particle sizes—smaller than 35 microns contributes to the sensation of creamy—and the balance between flavor and mouth time, such as the crunch of a crispy chip or the bounce of a chewy caramel.

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.

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.

Touch is the first sense a fetus develops in the womb

During gestation, our sense of touch begins to develop around 8 weeks, starting with the development of sensory receptors in the face and, about a month later, in the palms and soles of the feet.

Efforts to build touch-enabled machines highlight the complexity of human touch

The challenges that engineers are facing as they try to reproduce a human's ability to touch and also give robots the ability to interpret that kind of sensory flow are furthering our understanding of the myriad intricacies of human touch—and the challenges in emulating it.

When processing light, the brain can perceive colors with no natural wavelength

While some animals are sensitive to many forms of light, humans possess receptors that are sensitive to red, green, and blue wavelengths. These receptors send signals to the brain, which are processed and mixed to produce the array of colors we observe, including magenta, pink, and "supercolors" that lack a corresponding natural wavelength in the visible spectrum.

Touch deprivation can heighten anxiety and depression

Pacinian Corpuscles are pressure receptors just under the skin that send signals to the vagus nerve in the brain—that's the cranial nerve which regulates involuntary actions like breathing, heart rate, and the general "fight or flight" response. Activating those receptors can slow the heart, decrease blood pressure, and lead to the release of oxytocin and cortisol. The absence of touch, conversely, can promote negative feelings.

Many parts of the body, including the testicles, have bitter, sweet, and umami receptors

Taste receptors—the tiny cells that report the chemical makeup of external stimuli to the brain—in the testicles don't "taste" in the same way as the gustatory ones you use to determine if there's enough sugar in your tea. Research suggests that these "teste" receptors can sense bitter, sweet, and umami compounds and use that chemical input to control physiological processes or (literally) change direction. (Some users may experience a paywall.)

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.

Brain hemispheres control opposite sides of the body without either dominating

Although distinctions exist between the two halves—language processing is left-oriented, and emotions are right-oriented—signals are sent along neural pathways between the hemispheres and across different regions to collectively process information about external stimuli.

The brain doesn't seem to massively rewire following amputation—upending earlier beliefs about phantom pain

The findings, published in 2025, traced three amputees' brain-body maps and how they respond to body part movements—both before and after scheduled arm amputations. The unexpected neural stability suggests that the unchanged pathways for the missing limbs may explain why people continue to feel them so acutely.

Synesthesia: when sensation in one sense triggers an unrelated sense in the brain

The first reported clinical case of synesthesia dates back to the early 1800s, though the perceptual phenomenon may be much older than surviving records imply. This article by researcher Richard Cytowic details the scientific history of synesthesia, a neurological trait that causes some senses to overlap, giving color to numbers and flavors to names.

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

The brains of people who experience frisson have unique neural pathways

A small 2016 study aimed to investigate the behavioral and neural differences between 10 individuals who experience goose bumps when listening to music and 10 who typically don’t. Scientists reported that individuals experiencing musical chills had greater white matter connectivity in specific auditory, emotional, and social processing areas of the brain.

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.

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.

The most common types of touchscreens are capacitive and resistive

Capacitative screens are coated with a conductive material that creates a uniform electric field, which is disrupted by fingers. This disruption is registered by the device across a grid to determine where contact was made. Resistive screens identify touch when fingers push gap-separated sheets into contact with one another.

How do brain scans work?

There’s only one thing in our solar system sophisticated enough to study itself: the human brain. But this self-investigation is challenging because a living brain is shielded by skull, swaddled in tissue, and made up of billions of tiny cells. How do we study living brains without harming their owners? Two experts explain how the various techniques like EEGs, fMRIs, and PETs work in this TedEd talk.

Cochlear implants stimulate nerves inside the ear to provide the sensation of sound

In a surgical procedure, one part of the implant is placed under the skin behind the ear and electrodes are threaded into the cochlea in the inner ear. Another part of the implant sits behind the ear and picks up sound and then converts it into patterns of nerve stimulation.

What happens when we sleep

Sleep is a highly specialized and complex process that begins via signals from a region of the brain called the hypothalamus. As explained in this overview video from The Economist, the hypothalamus maintains our circadian rhythm by using light cues from our environment to regulate sleep via a compound known as melatonin. Once asleep, the brain begins the "sleep cycle" and progresses through the four stages of sleep over and over again each night.

After 25 people used virtual reality headsets to practice flying with virtual wings—flapping their arms—their visual cortex responded to the wings almost as if they were real arms, treating them as body parts.

'Artificial embryos': The hidden steps in forming a spine

Somitogenesis is the process by which segmented body structures like vertebrae form in embryos. While the process is well understood in animals like mice or zebrafish it is difficult to study in humans. But now, researchers have created a model of somitogenesis, using pluripotent stem cells, called an axioloid.

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

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

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.

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.

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.

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

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

Tattoos remain visible on your skin thanks to immune cells called macrophages

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 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.

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

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

Poison ivy is in the same family as mangoes, cashews, and pistachios—and they all produce oily urushiol in their raw, unprocessed state—but they are typically prepared in ways to avoid causing human discomfort.

The animatronic shark from Steven Spielberg's 'Jaws,' the first modern blockbuster, was a complex underwater apparatus called 'Bruce.'

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.

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

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

Art theft is the third-largest source of criminal revenues worldwide, thanks in part to the subjective nature of valuing a work of art.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks

An initial public offering or 'IPO' is the process of a private company becoming public by putting shares of the company on the stock market for purchase.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

The Brothers Grimm were lawyers before they were storytellers, and became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.