BRAIN CHEMICALS THAT MAKE US HAPPY OR SAD

you


WHY DO YOU FEEL?
Think back to a time when you felt excited and happy.Now, remember a time when you felt sad or disappointed or even angry.Have you ever thought about why you felt those things or why your body reacted the way it did when you experienced those emotions?You can thank some itty-bitty chemicals produced by nerve cells that are at work all throughout your body.

NEURONS CONTROL YOUR BODY
Cells are the basic building blocks of life.Your body is made up of trillions of cells!Nerve cells (also called neurons) are one of the body's NEURONS Cells that make up the brain, spinal cord, and nerves.They consist of dendrites, a cell body, and an axon.many cell types, and they have two main functions: to sense the outside world and to control your body's responses to the outside world.How do neurons do this?By working together!Neurons, which are found in the brain, spinal cord, and all other organs, communicate with one another using chemical signals to relay information throughout the body.They do this through their unique structure (Figure ).The cell body is the "main area" of the neuron.Dendrites are short branches extending from the cell body that receive chemical signals from other cells.The axon is a long,

AXON
The long thin part in the middle of a neuron that sends signals from the cell body to the axon terminal, releasing chemicals that lead to signaling in other neurons.
thin fiber extending from the cell body that branches out at the ends.The very ends of the branches are called axon terminals and they release chemical signals into the small space between two neurons, which is called the synaptic gap.So, in summary, a neuron receives

SYNAPTIC GAP
The space between the end of one neuron and the start of another neuron, which neurotransmitters cross for cell-to-cell communication.
signals through its dendrites, the signal moves through the cell body and down the axon, and is passed on at the axon terminals, so that another neuron can receive it.Together, neurons can control many things about us, including our emotions [ ].

WHAT ARE NEUROTRANSMITTERS?
What exactly are the signals sent between neurons?They are made of chemicals called neurotransmitters.Imagine two friends playing

NEUROTRANS-MITTERS
Chemical messengers that transfer signals from one nerve cell to another.a game of catch with a baseball.The "thrower" throws the ball across the lawn to the "catcher."Similarly, imagine two neurons are communicating using neurotransmitters (Figure ).The "thrower" neuron is called the presynaptic neuron-"pre" means "before" and tells us this neuron is before the synaptic gap.The presynaptic neuron releases the neurotransmitter across the "lawn" (synaptic gap), where it is caught by the "catcher" neuron, called the postsynaptic neuron (meaning "after" the synaptic gap).the synaptic gap, they bind to molecules called receptors on the RECEPTORS Structures on a cell that receive ("catch") molecules and can send a signal into the cell in response.In neurons, receptors trigger an electrical signal that travels through the cell.dendrites of the "catching" neuron-you can think of receptors as the "hands" doing the catching.When enough receptors "catch" the neurotransmitters, an electrical change is created in the receiving neuron, and this charge moves through the cell body and down the axon [ ].When the electrical signal reaches the end of the axon, the vesicles in the axon terminal release their neurotransmitters into the synaptic gap, and they travel across to communicate with even more neurons by the same method.This is the basic method by which the neurotransmitters in your brain influence the emotions you feel.
The three most common neurotransmitters involved in emotions are dopamine, serotonin, and norepinephrine [ ] (Figure ).These three di erent "balls" control your everyday moods and emotions!A good balance between "throwing" and "catching" each of these neurotransmitters is important to keep you physically and mentally healthy.

DOPAMINE
Dopamine is a neurotransmitter associated with emotions such as interest, enjoyment, fear, and anger.However, dopamine alone cannot cause these emotions [ ]. Dopamine is a special neurotransmitter that works together with other neurotransmitters, such as serotonin and norepinephrine, to form these emotions.Dopamine also works in the brain's reward system.Dopamine is released from neurons when the brain receives an unexpected reward, like when you receive a surprise gift [ ].However, too much dopamine can be problematic, as it is linked to addiction and a psychiatric disorder called schizophrenia.and norepinephrine do play a major role in our mood.So, whenever you feel happy, sad or anything in between, remember that these tiny chemicals are at work all over your body to make you feel that way.

CONFLICT OF INTEREST:
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figure
Figure

Figure
Figure Neurons consist of three main structures: dendrites, the cell body, and the axon.Dendrites receive signals from the environment or from other cells.The signals travel through the cell body and then down the axon, which passes the message on to more neurons across the synaptic gap.

FigureFigure
Figure , LeVaughn and Osier.This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.No use, distribution or reproduction is permitted which does not comply with these terms.YOUNG REVIEWERSC.R., AGE: I like rock music and playing soccer.Math is my favorite subject at school.I really do not know what else to add.JIA, AGE: I enjoy reading, watching shows and learning new things.I find science particularly facinating due to it being all around us.AUTHORSAMY KIM Hello!I am currently an undergraduate student at The University of Texas at Austin, pursuing a Bachelor of Science in biochemistry.After completing my degree, I plan to pursue a career in science.I hope to grow and learn in this field to help and serve others, and to ultimately be a positive influence on all those around me.In my free time, I enjoy singing, crocheting, and watching dramas.I find my faith to be a great source of comfort and motivation.PANISARA SUTTHIPONG I am an undergraduate student at the University of Texas at Austin pursuing a Bachelor of Science in medical laboratory science.I am on the pre-medical track.After graduation, I plan to attend medical school and become a pathologist.My goal is to become more involved in and educate people about the lesser-known aspects of healthcare, such as laboratory work.In my spare time, I enjoy playing the violin in UT's University Orchestra, drawing in my sketchbook, making digital art on my tablet, and playing games with my friends.MYA LEVAUGHNI am an undergraduate student at the University of Texas at Austin pursuing a Bachelor of Science and Arts in neuroscience.After completing my bachelor's degree, I plan to attend medical school in hopes of increasing diversity in healthcare and providing greater comfort for patients from various backgrounds.I love spending my free time hiking, swimming, and painting.principal investigator at the University of Texas at Austin.I have a bachelor's degree in nutritional science and nursing from Michigan State University, and a Ph.D. from the University of Pittsburgh.I am fascinated by the brain and how it impacts people throughout their lives.To learn more about my laboratory, visit my publicly available website: https://nicoleosier.wixsite.com/osierlaboratory/or follow @osierlaboratory on Facebook, Twitter, or Instagram.In my free time, I enjoy traveling the world.*nicoosier@utexas.edu If you are denied an expected reward, like if you find out your favorite show was canceled, dopamine activity is decreased [ ].Low dopamine levels are associated with emotions like surprise, distress, shame, and disgust [ ].Even lower levels are associated with anxiety and Parkinson's disease, a nervous system disease that causes movement di culty.Thus, one treatment for such conditions includes a special chemical that helps the body create more dopamine, which reduces symptoms [ ]. dish, you will know it is from the serotonin firing in your brain.Extremely high levels of serotonin in neurons can lead to serotonin toxicity, which involves symptoms such as nervousness, insomnia, nausea, and shaking [ ].
SEROTONINSerotonin is a neurotransmitter associated with emotions such as interest, enjoyment, and surprise.It is also related to disgust, as stimulation of serotonin receptors is linked with disliking the taste of a food [ ].The next time you feel disgusted from eating your most hatedNOREPINEPHRINENorepinephrine is a neurotransmitter that plays a key role in attention and alertness as well as in the "fight or flight" response.During times of stress or anxiety, norepinephrine is released and binds to receptors throughout the body.This increases heart rate, dilates pupils, slows down digestion, and heightens the senses-a reaction you may have felt at a time when you were nervous or scared [ ]. High levels of norepinephrine make you feel active, aroused, and attentive.three neurotransmitters are at high levels, we can feel interest and excitement, while having all three at low levels can generate feelings of shame and humiliation [ ].Control of feelings, thoughts, and actions is complex and are a ected by other factors than the three neurotransmitters discussed in this article.Still, serotonin, dopamine,