2e. 5 Senses
You’re already familiar with your five senses: smell, taste, touch, hearing and sight. And you’ve obviously learned that eyes are used for seeing, ears for hearing and so on. That’s certainly true but in reality, your brain does most of the heavy lifting for your senses. It’s more accurate to say that your eyes, ears, tongue and nose are collecting sensory information and sending it off to the brain for processing.
You don’t need to be a brain scientist to understand a bit more about how your brain sees, smells, tastes, hears and touches. Expand the accordions to learn more.
As you breathe in, nerves in your nose collect and send information about smells to an area of the frontal lobe called the olfactory bulb. Located right between your eyes, the olfactory bulb processes and identifies the smell. When you eat, your nose also collects smell information, making a lot of what we call taste actually a smell!
Fast fact: Ever smell something and have a memory or emotion pop up out of nowhere? In the brain, the olfactory bulb is right next to the amygdala and hippocampus. These brain parts process emotion and memory, which explains why both can be strongly linked with smells.
When you eat or drink, information about taste is collected by your tongue through little nerves found on your tastebuds. From there, the taste info is sent to your brainstem and then into your brain for processing and identification. Different areas of your brain are specialized to detect tastes, like salty and sweet.
Fast fact: Some people, called supertasters, have extra nerves in their taste buds which gives them a stronger sense of taste.
All throughout your skin, you have nerves that alert you to sensations like pressure, pain and temperature. The nerves pass information to your spinal cord, up through the brainstem and into the cerebrum, where the information is processed.
Fast fact: In some cases, your body can react to touch before the information even reaches the brain. If you step on a tack, your spinal cord can process the painful touch information and send the signal to lift your foot. You don’t feel the pain until after your foot’s up!
Hearing
Sounds enter your ear as vibrations, which travel into a snail shaped area of the inner ear called the cochlea. The vibrations make tiny hairs wiggle, which then activates nerves attached to the hairs. The nerve signals are sent to the temporal lobe for processing. The brain can interpret info from the nerve signals, like what direction the sound came from, how loud it was and whether or not you recognized the sound. Like many brain functions, hearing isn’t fully understood.
Fast Fact: Cochlear implants can restore hearing for people who are deaf. These implants work by creating tiny vibrations from sound, which are captured by the inner ear nerves and passed to the brain.
Just like all the other senses, sight is a complex process! Your eyes take in visual information and pass it through nerves to the occipital lobes for initial processing. From there, information is sent to the parietal, temporal and frontal lobes where your brain figures out things like what you’re looking at, where it’s located, and how you can reach the object.
Fast Fact: Color blindness can be caused by faulty cells in the eye. These cells, called cones, come in 3 types and are named for the colors they detect: red, blue and green. If one or more types of cone cells are faulty, nerve signals aren’t sent for that color and the person can’t see it.
