A Guide to Neuroscience
By William Huang
First off, let’s start with a hypothetical scenario regarding Baby Martin. Before he is 10 months old, his mother notices that his body is stiff when she picks him up, and his back and neck overextend. As he grows older, his mom notices that he didn’t reach normal milestones like his other siblings did. He cannot roll over, bring his hands together, or crawl on all fours.
Martin’s mother then takes him to a child neurologist, who orders a CT and an EEG. She also notes his symptoms. After running tests to rule out similar neurological disorders, his doctor diagnoses him with cerebral palsy, which is a group of disorders that affect a person's ability to move and maintain balance. It occurs as a result of a brain injury sustained during fetal development or birth.
Now we are going to go back to the basics. Martin had a neurological disorder, which is often studied in neuroscience. It is an interdisciplinary science which takes into account other disciplines, such as mathematics, linguistics, engineering, computer science, chemistry, philosophy, psychology, and medicine. Humans have an estimated hundred billion neurons, or brain cells, and these neurons have thousands of other connections. Modern neuroscience aims to map out all the networks of cell-to-cell communication, which encompasses the brain’s circuits that process all thoughts, feelings, and behaviors. The resulting picture is known as "the connectome." In other words, the brain is wired with all sorts of neural connections. These connections link together the various lobes in the brain and also link sensory input and motor output with the brain’s message centers, allowing information to come in and be sent back out.
I will begin with an important part of neuroscience: the nervous system.The nervous system can be divided into the peripheral and central nervous systems. The central nervous system consists of the brain and spinal cord. It plays a central role in the control of most bodily functions, including awareness, movements, sensations, thoughts, speech, and memory. The peripheral nervous system (PNS) encompasses nerves outside the brain and spinal cord. This system is further divided into the autonomic and somatic nervous system. The autonomic nervous system is a control system that acts largely unconsciously and regulates bodily functions, such as the heart rate, digestion, and breathing rate. The somatic nervous system controls voluntary body movements via the skeletal muscles. This system consists of afferent nerves or sensory nerves, and efferent nerves or motor nerves.
Neurons are the cells of the nervous system. Neurons, or nerve cells, are the fundamental units of the brain and nervous system. These cells are responsible for receiving sensory input from the external world, for sending motor commands to our muscles, and for transforming and relaying the electrical signals sent from our brain. These cells are especially important because they define who we are as people. The three main parts of the neuron are the cell body, axon, and dendrites. The cell body contains the nucleus and cytoplasm. The axon is responsible for transmitting the electrical signals that neurons send or receive. It is covered in a myelin sheath, which speeds up the transmission of these signals. These signals are the result of a neuron’s action potential. The next part is the dendrites, which extend from the neuron cell body and receive messages from other neurons. They contain the synapses, which is where neurons communicate with each other.
Finally, the brain. The hindbrain consists of structures in the top part of the spinal cord. It controls basic biological functions, and it contains the medulla, pons, and cerebellum. The medulla controls blood pressure, heart rate, and breathing. The pons connect the hindbrain with the midbrain and forebrain. It also controls facial expressions. The cerebellum, which means little brain, coordinates muscle movements, such as playing an instrument.
Citations:
https://neuro.georgetown.edu/about-neuroscience/
https://www.medicalnewstoday.com/articles/248680
https://www.medicalnewstoday.com/articles/307076
https://qbi.uq.edu.au/brain/brain-anatomy/what-neuron
https://www.webmd.com/brain/picture-of-the-brain
Image Credit
https://www.ppd.com/therapeutic-expertise/neuroscience/
