Discover human limits through 5 senses

Hearing, taste, sight, smell and touch are 5 human senses that help us feel the stimuli of the environment outside the body. The limits of these sensory organs are the limits of the human body itself.

1. Decode interesting things that happen inside the nose when we smell
2. How do animals see the world far beyond humans?

Therefore, learn the limits of the 5 senses to know what endurance people can reach "peak".

1. Vision

It can be said that vision is the most important sense, because 1/4 of the neural neurons are needed to receive and process image information.

The limit of sight

For a healthy person, the two eyes will have a total viewing angle of 200 degrees horizontally. Including:

1. The general viewing angle of both eyes is about 120 degrees.
2. The vertical viewing angle is 135 degrees.

Depending on the location of the eyes on the faces of each person, these angles may vary.

The human eye can see the galaxy of Andromeda 2.6 million light-years from Earth.

The human eye consists of many light-receiving cells that receive and transfer image information to the brain through the optic nerves.

The optic nerve must travel through the layer of photoreceptors behind the eyeball, making this point without the nerve to receive light meaning that it cannot receive light. That point is called blind spot .

Because the brain receives information from both eyes to compensate for the defects of each eye separately, blind spots are not a big problem for people. But when forced to use only one eye, blind spots cause many difficulties for people, can even be dangerous when moving at high speed.

Anatomy of human eye anatomy.

The number of light particles or photons that the object emits determines the vision of the human being, the more particles are emitted, the easier it is to stimulate the retina in the eye. Specifically, people are able to see a flickering fire with a distance of up to 48km. And amazingly, the farthest visible object is located 2.6 million light-years from Earth, the far-away Andromeda galaxy in the universe.

Hearing

Hearing is a very important sense, in some cases it can also help people avoid risks, overcome their vision.

We hear the sound thanks to a barrier located deep inside the ear called the eardrum. When the external noise enters the ear with the eardrum, the eardrum will vibrate to produce sound waves and continue to be transmitted through the small bones into the inner ear, and then converted into nerve signals to the brain.

A healthy person can hear audio frequencies between 20 and 20,000Hz.

Describe the threshold of hearing thresholds of people.

Each person's listening threshold is different, varying with age and depends on the frequency of the sound. The maximum listening threshold gradually decreases with age. The minimum hearing threshold is the term for the smallest sound intensity (when there is no disturbing sound) the human ear can hear. The minimum listening threshold of a normal person is 0 - 5 decibels (dB), as the sound of leaves falling to the ground, the sound of dripping water from the tap down to the sink. But statistically, some people even have the ability to hear the minimum sound intensity down to -5 dB.

The biggest sound that people can hear is about 160dB, if hearing the sound above the threshold can cause the eardrum to tear. If you hear a loud sound of 200dB, people can break their lungs, block blood vessels and lead to death due to excessive pressure.

Taste and taste

According to US scientists, the human nose can smell up to 1,000 billion smells. What a surprising "number" for many people.

Taste and smell are governed by two different receptors but each closely related to each other is the tongue and nose. If a sensory agency has problems, it will affect the other agency. For example, when you have a stuffy nose, the taste of the food will decrease significantly.

According to scientists, taste is considered to be the weakest of 5 human senses. Because taste is easily "fooled" if there is an effect of smell or even color.

But, there are still some special individuals who have "super" taste. The tongue of these people has more taste buds than others, making it more sensitive to the 4 basic tastes: sour, salty, bitter, sweet.

Taste buds on the tongue of the "super tasting" (above), of the normal person (below).

Tactile

Currently, scientists have not yet given the limit of human sense of touch. Because they have not grasped the mechanism of formation and feelings, the cause is due to the nerves under the skin.