Human: The World Within

Science and Nature Series / 1 Season

Explore the incredible universe inside each and every one of us. An examination of diverse personal stories from around the world reveals how our lives, passions and goals are powered by the amazing systems that define our biology as a species.

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Episode 6 Preview | React

30s / TV-PG

Through the lens of a boxer, a first responder, a cell tower climber and a man with a bionic limb, go deep into the universe of the most powerful machine on earth: the human brain and the vast nervous system it controls.

Data Processing in the Brain

2m 43s / TV-PG

All sight is translated into electrical impulses via the retina to the brain. The eye picks up information in the form of light. This light is instantaneously transformed into electricity, which shoots up to the brain. Once there, the electricity is decoded and formed into a picture. The information is traveling at speeds nearing 300mph, and the stream of data never stops.

How Pain is Processed in Our Nerves

1m 42s / TV-PG

Pain is a phenomenon that is deeply intertwined with the brain and nervous system. When something is wrong with the body, signals travel to our brain as neural impulses. These impulses are then interpreted by the brain as pain, which is basically the body's signal to us that we need to fix something.

An Introduction to the Brain and Neurons

1m 9s / TV-PG

The brain is mission control of the human body and the nervous system. Its 100 billion cells are processing data an incredible speeds. The brain coordinates not only the major functions of the body, but it also is the hub where information is interpreted and stored, and then turned into action. We have the brain to thank for the unique abilities of our species.

The Human Body's Nervous System

1m 22s / TV-PG

An introduction to the amazing functions of the human body's nervous system. This extremely advanced part of our biology is always at work interpreting the world we encounter and helping us decide what to do, and how to react. The secrets of our thoughts and decisions are locked into this astonishing network of cells, nerves, and fibers.

Engineering Lost Function Inside the Body

2m 45s / TV-PG

Jason Little lost his hand in a car accident, which he thought meant the end of being able to sense touch in that part of his body forever. Years later, he's now the first user of a new wireless interface that connects to his prosthetic arm and allows him to actually feel things in his phantom limb. His brain is able to interpret new signals in a way they once did.

Episode 5 Preview | Sense

30s / TV-PG

Dive into the stories of a pairs figure skating team, a perfumer, a cave explorer and a musician to decipher how different ways of sensing the world all create their own vivid and unique picture.

The Adaptive Quality of Our Senses

2m 53s / TV-PG

When we lose one of our senses, the loss isn't something the body can't handle. It just means that the brain has to figure out a new way of filling the void left by the information that's no longer there. Our bodies are actually incredibly adaptable when it comes to compensating for missing sensation.

The Human Body's Five Senses

1m 31s / TV-PG

An introduction into the amazing functions of the human body's five senses. Our bodies are constantly absorbing different kinds of information from the outside world. Sights, sounds, smells, tastes, feelings. Inside the body all of these things are pieced together to create our individual reality.

Proprioception - The Sixth Sense

2m 46s / TV-PG

It doesn't usually make the list of the five most important human senses, but proprioception is fundamental. It's our sense of where our bodies exist in space. We can feel where our hand is or where our feet are without looking at them. And we can move them accordingly because of that innate sense.

Episode 4 Preview | Defend

30s / TV-PG

Look at a nature survivalist, rancher twins, a doctor who survived Ebola and the recipient of a cutting-edge cancer therapy to uncover the wildly advanced biology that keeps us alive against all odds.

Episode 3 Preview | Fuel

30s / TV-PG

Through the worlds of a religious faster, an ultra-marathon runner, a farmer and a young girl beating allergies, go deep into the world of the human gut, which processes the fuel our bodies need to keep going.

The Gut Microbiome is the Hub of Our Immune System

2m 23s / TV-PG

The microbiome is the cutting edge of gut science. It's an ecosystem that's made up of trillions of bacteria that instead of making us sick, actually have a big hand in keeping us healthy. When this population of microbes is thriving and in check, it does wonders for the body.

The Digestive System

2m 6s / TV-PG

An introduction to the amazing functions of the human body's digestive system. Our continued survival as individuals and as a species requires energy. And we get that by extracting nutrients from the food we eat. Our digestive system has the job of refining everything we eat into raw power.

Episode 1 Preview | Birth

30s / TV-PG

Go on a journey with parents who are preparing for babies to see how our bodies create and sustain new life. Through their stories, we learn about what is fundamentally shared and absolutely unique about the experience of birth.

Episode 2 Preview | Pulse

30s / TV-PG

Dive into the world of an ice climber, a bus driver, a woman in labor and a senior dance club to show how the human heart and the circulatory system power our physical and emotional lives and create the pulsing rhythm of our world.

Blood Vessels and Circulatory Movement

2m 8s / TV-PG

Staying active and on the move is crucial to our health for a lot of reasons. But it's especially important for the circulatory system to function properly. In fact, our bodies are actually designed so that blood circulation depends on us being in semi-constant motion.

The Science Behind the Pulse in Our Bodies

2m 39s / TV-PG

It's the circulatory system that provides every cell in our body with the juice they need to function. The human body can only survive about three minutes without oxygen, and it's this incredibly vast network that is responsible for delivering this life-giving gas to all 40 trillion cells in the body.

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