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Middle school biology - NGSS
Course: Middle school biology - NGSS > Unit 1
Lesson 4: Sensory processing and the brainSensory processing and the brain
Each sense receptor responds to different inputs (electromagnetic, mechanical, chemical), transmitting them as signals that travel along nerve cells to the brain. The signals are then processed in the brain, resulting in immediate behaviors or memories. Created by Khan Academy.
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- How does smell work? Why does our brain make some very healthy foods smell bad? Why does the sensory cells in our noses sense things? I guess it could work with the seeing sense. Like if you were to see something gross you would probably think it smells gross. Do those two work together? If so, how do some things smell different from blin people to people who can see?(11 votes)
- This is a lot of questions. I'll try to take them one at a time.
1. Smell is a chemical sense. High in your nose are olfactory sense neurons, that pick up molecules that are produced by many things around us. These molecules are smells, and they stimulate the olfactory neurons to produce the signals to send to your brain. Each olfactory receptor is stimulated by one molecule, but many smells exist by activating many of those receptors to create a unique signal to send to the brain.
2. Things smell bad when they activate certain unsatisfactory receptors in your nose that your brain processes that it doesn't like.
3. I think I answered your third question at the beginning, but to reiterate, those sensory cells are all activated by specific molecules striking the cell and setting off a reaction
4. I believe some studies have been done that connect sight to smell, and that they have come out with results in the way you are describing. However, taste and smell are more connected. When you chew something, it releases odors that travel up from your mouth to your nose and set off a reaction along with your taste receptors. If your brain doesn't like these odors (or the taste), odds are you don't like the food. This is the case with many healthy foods. This is why when your nose is clogged, your taste can disappear. But I've gotten a little off topic. I believe sight and smell are connected, yes, and that sight can affect what you smell (though less in a chemical and more in a psychological sense); however, they are connected to a much smaller extent than taste and smell are connected.
5. I don't know of any studies being done on whether things smell better to the blind than the sighted, so I am unable to answer this one. However, I do encourage you to do your own research to see if you can find an answer to this question. If you find anything, could you let me know?
I apologize for the long answer (it's kind of a habit for me), but I hope this helps you.(31 votes)
- does blind people dream(9 votes)
- their dreams consist of voices because if you've never seen it you can't dream of it(4 votes)
- why do some people think something tastes bad and others not? Is that an entirely different part of our brain?(6 votes)
- It's just different people liking different tastes. There is no practical difference in the taste that people perceive.(4 votes)
- yummy Chicken Noodle Soup!i lov it!(7 votes)
- she made it look so good :'((1 vote)
- Where are you all from (including teachers)?
I live in New Zealand(4 votes)- I'm from EARTH
not a very good place to live. would not recommend. 2 stars smh(3 votes)
- by the way yall im new to this school program so i dont have many points(5 votes)
- Chicken noodle soup again. 😉(5 votes)
- What kind of stimulant is pain?
And would hard bread be a mechanical or chemical stimulant(3 votes)- pain is a touch stimulant! think about how you don't necessarily taste a cookie and feel pain, or hear toccata and fugue in d minor and feel pain, but you could stub your toe on a chair leg (you're touching something!) and feel pain.
to be honest, i'm not sure, but i think it's mechanical. an apple is hard-ish and it's not really chemical, so i'm assuming it's the same for bread?(5 votes)
- question how come the body simply cant just say [ oh i dont wanna feel pain anymore so what ever that would make life so much better(3 votes)
- Because the nerves are being stimulated with pain (I.e. getting hit in the arm) so they won’t just stop giving you pain.(4 votes)
- At(to 2:37) Does your brain still store information if you have ADHD? Or does it not save that information because of what ADHD can do to your brain. Asking as an ADHD person. 2:49(4 votes)
- I have ADD and you can still remember things just not as well.
Try decaf coffee, it helps me with my ADD(2 votes)
Video transcript
- [Narrator] As humans,
we have a lot of senses that we put to use on a regular basis. They include sight, smell,
taste, touch, and hearing. But have you ever
wondered how it all works? How do you look at a beautiful
painting in an art museum, or smell the rain outside on a stormy day, or feel that your favorite pair of socks are still a little damp, and need another cycle in the dryer? How does that information make its way from our sensory organs to our brains? Well, the answer lies
in the nervous system. If you remember, our bodies are made up of multiple complex organ
systems that work together to perform all different
kinds of functions. Today, let's talk specifically
about the nervous system, which is an organ system that allows us to sense and respond to our environment. To begin, the nervous system
contains specialized cells and cell parts, called sensory receptors, which are able to pick up
signals from the environment. These signals are called stimuli, or stimulus if you're
talking about just one. Stimuli can come in many different forms. For instance, mechanical
stimuli are physical in nature, and are involved with our
senses of touch and hearing. You can strum a guitar, feeling the strings
against your fingertips, and listening to the
unique tones it produces as the strings vibrate. Those are all mechanical stimuli. Chemical stimuli are made up of molecules, and are involved with our
senses of smell and taste. To illustrate an example, imagine eating a tasty bowl
of chicken noodle soup. As you spoon mouthfuls
of soup into your mouth, your taste and olfactory receptors are flooded with molecules that signal the qualities
of the food you're eating. These molecular signals
are chemical stimuli. And in this case, the molecules from the chicken noodle soup convey that the food
you're eating is savory, and extremely delicious. Lastly, electromagnetic stimuli are involved with our sense of sight, and include the light that
comes into our eyes every day. The sunlight that makes you squint, the traffic lights you see on the street, and the vibrant and diverse
colors all around you. These are just a few examples of electromagnetic stimuli
in the form of light. So then what happens after
sensory receptors detect stimuli? Well, once a sensory receptor
receives the information, it passes this information
along nerve cells. Here's a picture of a nerve cell, which is specialized
to transmit information in the form of electrical signals. These signals are transmitted
along nerves to the brain, which is then responsible for processing, or organizing sensory information from different sensory receptors. After processing the information, the brain can elicit a response, and also store the information
in the form of a memory for future use. For example, imagine you're playing catch with friends in a park. Your sensory receptors pick up information as you watch the ball come towards you, and feel the wind on your skin. Signals from these receptors travel along nerve cells to your brain, where all these different
signals are organized. Then your brain elicits a response, such as moving to just the right spot, and putting your hands
out to catch the ball. And the brain also stores a memory, perhaps remembering playing catch as a fun activity that
you'd wanna do again. You can almost think of
this flow of information from a stimulus to sensing, to processing, and finally, to eliciting a
response or storing information, like a complex relay race. Sensory receptors pick up
message in the form of stimuli, and pass this information along
to nerves, and to the brain. Only in this relay, the end
result at the finish line is a response to the stimulus
and information storage. So to summarize, today, we talked about
how our bodies sense, and respond to the environment. Information is transferred from a stimulus to a sensory receptor, to nerve cells, and finally to the brain,
where processing occurs. Whether we're aware of it or not, our nervous system is working
at rapid-fire speed every day to provide us with the information our bodies need to sense
what's in our environment, and thrive in it.