Location And Basic Physiology
In vertebrate anatomy, the brainstem is the most inferior portion of the brain, adjoining and structurally continuous with the brain and spinal cord. The brainstem gives rise to cranial nerves 3 through 12 and provides the main motor and sensory innervation to the face and neck via the cranial nerves. Though small, it is an extremely important part of the brain, as the nerve connections of the motor and sensory systems from the main part of the brain that communicate with the peripheral nervous system pass through the brainstem. This includes the corticospinal tract , the posterior column-medial lemniscus pathway and the spinothalamic tract . The brain stem also plays an important role in the regulation of cardiac and respiratory function. It regulates the central nervous system and is pivotal in maintaining consciousness and regulating the sleep cycle.
How Is Blood Pressure Regulated
Both divisions of the Autonomic Nervous system, the Parasympathetic and Sympathetic Nervous systems regulate blood pressure. They act like the gas and brake pedals in a vehicle by increasing and decreasing the blood pressure when it begins to move outside of the bounds of normalcy, the Sympathetic being the gas pedal and the Parasympathetic being the brake.
This subtopic will be explained more in depth in the next article, Blood Pressure Regulation at a Glance: How Determinants Affect Blood Pressure.
What Sort Of Body Functions Does The Hypothalamus Influence
The hypothalamus plays a significant role in the endocrine system. The function of the hypothalamus is to maintain your bodys internal balance, which is known as homeostasis. To do this, the hypothalamus helps stimulate or inhibit many of your bodys key processes, including: Heart rate and blood pressure.
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Common Symptoms Of Stroke
Symptoms of stroke depend on which area of the brain is affected. A stroke in the brain stem can interfere with vital functions such as breathing and heartbeat. Other functions that we perform without thinking, such as eye movements and swallowing, can also be altered. Brain stem stroke can also impair your speech and hearing, and cause vertigo.
All of the signals from your brain move through the brain stem to reach the different parts of your body. Nerve cells that come from various sections of the brain carry these signals right through the brain stem to the spinal cord.
When blood flow in the brain stem is interrupted, such as with stroke, those brain signals are also disrupted. In turn, the different parts of the body that these signals control will also be affected. This is why some people experience numbness on one or both sides of the body, or paralysis in their arms or legs.
Anatomy Of The Nervous System
If you think of the brain as a central computer that controls all bodily functions, then the nervous system is like a network that relays messages back and forth from the brain to different parts of the body. It does this via the spinal cord, which runs from the brain down through the back and contains threadlike nerves that branch out to every organ and body part.
When a message comes into the brain from anywhere in the body, the brain tells the body how to react. For example, if you accidentally touch a hot stove, the nerves in your skin shoot a message of pain to your brain. The brain then sends a message back telling the muscles in your hand to pull away. Luckily, this neurological relay race takes a lot less time than it just took to read about it.
Considering everything it does, the human brain is incredibly compact, weighing just 3 pounds. Its many folds and grooves, though, provide it with the additional surface area necessary for storing all of the bodys important information.
The spinal cord, on the other hand, is a long bundle of nerve tissue about 18 inches long and ¾ inch thick. It extends from the lower part of the brain down through spine. Along the way, various nerves branch out to the entire body. These make up the peripheral nervous system.
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Blood Pressure Control In Times Of Stress
In other cases, your blood pressure may fall suddenly, such as when you are injured and lose a lot of blood . In addition to triggering changes in your heart beat and blood vessel walls, the sudden drop in blood pressure will also trigger the release of hormones that affect your kidney function . If you lose a lot of blood, your body senses the drop in blood volume and triggers the productions of hormones that signal the kidneys to retain salt and water . This increases your blood volume, thereby increasing blood pressure .
What Is The Gray Matter And White Matter
Gray and white matter are two different regions of the central nervous system. In the brain, gray matter refers to the darker, outer portion, while white matter describes the lighter, inner section underneath. In the spinal cord, this order is reversed: The white matter is on the outside, and the gray matter sits within.
Gray matter is primarily composed of neuron somas , and white matter is mostly made of axons wrapped in myelin . The different composition of neuron parts is why the two appear as separate shades on certain scans.
Each region serves a different role. Gray matter is primarily responsible for processing and interpreting information, while white matter transmits that information to other parts of the nervous system.
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How Does The Brain Work
The brain sends and receives chemical and electrical signals throughout the body. Different signals control different processes, and your brain interprets each. Some make you feel tired, for example, while others make you feel pain.
Some messages are kept within the brain, while others are relayed through the spine and across the bodys vast network of nerves to distant extremities. To do this, the central nervous system relies on billions of neurons .
Why Is Regulation Needed
As blood is pumped from the heart to the various blood vessels, enough pressure is generated in order to send blood to all parts of the body. As the blood travels further from the heart, they branch off and gradually decrease in size, much like the branches of the tree. One branch may travel to the stomach, while another may transport blood to the muscle and yet another to the brain, etc.
Blood pressure keeps the blood flowing through all these branches so that the cells of the body can receive the oxygen and nutrients needed to sustain life.
When the heart contracts, pressure built up in the blood vessels increases as the blood passes through, while the opposite is true when the heart relaxes in between heart beats. For the blood to be able to reach all of the vitals organs, healthy, elastic blood vessels that will stretch and recoil as the pressure goes up and down respectively, are needed.
Persons who suffer from hypertension, their small blood vessels in vitals organs are most often affected over time. These vessels become scarred, harden and inelastic, which means they are more likely to get blocked or worse rupture which could lead to organ damage and even the failure of these organs in some cases. So it is important to regulate hypertension to reduce the risks of:
- Organ damage
- Heart attacks
So, we see regulation of blood pressure is of utmost importance for our survival!
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Everyday Blood Pressure Control
Blood pressure changes throughout the day. It’s lower when you are asleep or resting, and higher when you are active or excited . Your body quickly adjusts to these changes by controlling your heart beat and blood vessel diameter . For example, when you begin exercising, blood pressure increases . The pressure sensors in your blood vessels detect this increase and send messages to your brain to slow the beating of your heart, lower the strength of your heart’s contractions and relax blood vessel walls to reduce blood pressure . Or, when you quickly move from a lying to a standing position, blood pressure drops . Your body senses this and increases heart rate and force of contractions, and constricts blood vessel walls to increase your blood pressure .
High Pressure Short Memory
Since hypertension damages blood vessels, it’s easy to see how it contributes to vascular dementia. Although the link to Alzheimer’s disease is less obvious, research suggests that vascular damage and tissue inflammation accelerate injury.
The details vary from study to study, but the weight of evidence now suggests that high blood pressure increases the risk of mild cognitive impairment, vascular dementia, and even Alzheimer’s disease. Both systolic and diastolic hypertension take a toll in general, the higher the pressure and the longer it persists without treatment, the greater the risk.
Most investigations focus on older adults. For example, a study of 2,505 men between the ages of 71 and 93 found that men with systolic pressures of 140 mm Hg or higher were 77% more likely to develop dementia than men with systolic pressures below 120 mm Hg.
Doctors may be able to help ease the burden of dementia, but the damage and disability cannot be reversed. That makes prevention doubly important. Can treating hypertension help prevent dementia?
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How Does The Nervous System Work
The basic workings of the nervous system depend a lot on tiny cells called neurons. The brain has billions of them, and they have many specialized jobs. For example, sensory neurons send information from the eyes, ears, nose, tongue, and skin to the brain. Motor neurons carry messages away from the brain to the rest of the body.
All neurons relay information to each other through a complex electrochemical process, making connections that affect the way you think, learn, move, and behave.
Intelligence, learning, and memory. As you grow and learn, messages travel from one neuron to another over and over, creating connections, or pathways, in the brain. It’s why driving takes so much concentration when someone first learns it, but later is second nature: The pathway became established.
In young children, the brain is highly adaptable. In fact, when one part of a young child’s brain is injured, another part often can learn to take over some of the lost function. But as you age, the brain has to work harder to make new neural pathways, making it harder to master new tasks or change set behavior patterns. That’s why many scientists believe it’s important to keep challenging the brain to learn new things and make new connections it helps keeps the brain active over the course of a lifetime.
Smell. Olfactory cells in the mucous membranes lining each nostril react to chemicals you breathe in and send messages along specific nerves to the brain.
Right Brain Left Brain
The cerebrum is divided into two halves: the right and left hemispheres They are joined by a bundle of fibers called the corpus callosum that transmits messages from one side to the other. Each hemisphere controls the opposite side of the body. If a stroke occurs on the right side of the brain, your left arm or leg may be weak or paralyzed.
Not all functions of the hemispheres are shared. In general, the left hemisphere controls speech, comprehension, arithmetic, and writing. The right hemisphere controls creativity, spatial ability, artistic, and musical skills. The left hemisphere is dominant in hand use and language in about 92% of people.
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What Part Of The Brain Controls Breathing
The brain is the very center of our being. It houses our habits, emotions, and controls all bodily functions.
Breathing is an automatic process we often dont pay much attention to. But have you ever stopped to think about what part of the brain controls breathing?
The brain is responsible for interpreting sensory data, filtering our emotions, regulating our sleep patterns, and of course, our breathing.
Heres what you need to know about what part of the brain controls breathing.
The Cell Structure Of The Brain
The brain is made up of two types of cells: neurons and glial cells, also known as neuroglia or glia. The neuron is responsible for sending and receiving nerve impulses or signals. Glial cells are non-neuronal cells that provide support and nutrition, maintain homeostasis, form myelin and facilitate signal transmission in the nervous system. In the human brain, glial cells outnumber neurons by about 50 to one. Glial cells are the most common cells found in primary brain tumors.
When a person is diagnosed with a brain tumor, a biopsy may be done, in which tissue is removed from the tumor for identification purposes by a pathologist. Pathologists identify the type of cells that are present in this brain tissue, and brain tumors are named based on this association. The type of brain tumor and cells involved impact patient prognosis and treatment.
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Lobes Of The Brain And What They Control
Each brain hemisphere has four sections, called lobes: frontal, parietal, temporal and occipital. Each lobe controls specific functions.
- Frontal lobe. The largest lobe of the brain, located in the front of the head, the frontal lobe is involved in personality characteristics, decision-making and movement. Recognition of smell usually involves parts of the frontal lobe. The frontal lobe contains Brocas area, which is associated with speech ability.
- Parietal lobe. The middle part of the brain, the parietal lobe helps a person identify objects and understand spatial relationships . The parietal lobe is also involved in interpreting pain and touch in the body. The parietal lobe houses Wernickes area, which helps the brain understand spoken language.
- Occipital lobe. The occipital lobe is the back part of the brain that is involved with vision.
- Temporal lobe. The sides of the brain, temporal lobes are involved in short-term memory, speech, musical rhythm and some degree of smell recognition.
How The Body Maintains Blood Pressure
Here are 10 lifestyle changes you can make to lower your blood pressure and keep it down.
Also Know, how does the brain control blood pressure? Signaling the brain to lower blood pressure. Stimulating the baroreceptors causes them to send signals to the brain. The brain interprets these signals as a rise in blood pressure. It responds by sending signals to the heart, kidneys, and blood vessels to lower blood pressure.
how does homeostasis maintain blood pressure?
They send impulses to the cardiovascular center to regulate blood pressure. At lower blood pressures, the degree of stretch is lower and the rate of firing is slower. When the cardiovascular center in the medulla oblongata receives this input, it triggers a reflex that maintains homeostasis.
Why is it important to regulate blood pressure?
A. Blood pressure is important because the higher your blood pressure is, the higher your risk of health problems in the future. If your blood pressure is high, it is putting extra strain on your arteries and on your heart. This may also cause a heart attack or stroke.
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What Is The Medulla Oblongata And What Does It Do
For most of the 18th century, the medulla oblongata was thought to simply be an extension of the spinal cord without any distinct functions of its own. This changed in 1806, when Julien-Jean-Cesar Legallois found that he could remove the cortex and cerebellum of rabbits and they would continue to breathe. When he removed a specific section of the medulla, however, respiration stopped immediately. Legallois had found what he believed to be a “respiratory center” in the medulla, and soon after the medulla was considered to be a center of vital functions .
Over time, exactly which “vital functions” were linked to the medulla would become more clear, and the medulla would come to be recognized as a crucial area for the control of both cardiovascular and respiratory functions. The role of the medulla in cardiovascular function involves the regulation of heart rate and blood pressure to ensure that an adequate blood supply continues to circulate throughout the body at all times. To accomplish this, a nucleus in the medulla called the nucleus of the solitary tract receives information from stretch receptors in blood vessels. These receptors—called baroreceptors—can detect when the walls of blood vessels expand and contract, and thus can detect changes in blood pressure.
The Vasomotor Control Center
The vasomotor center controls the size of the body’s blood vessels. When a person is stressed or in danger, the vasomotor center makes the blood vessels get smaller. This is part of the body’s “fight or flight” reaction. It causes more blood to go to the body’s most important organs, like the brain, heart, and lungs. This can help a person survive if they are in danger. It also makes the blood pressure go up.
At other times, the vasomotor center makes the blood vessels get wider. This makes the blood pressure go down, and makes it easier for blood to get to some parts of the body.
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What Are The Parts Of The Nervous System
The nervous system is made up of the central nervous system and the peripheral nervous system:
- The brain and the spinal cord are the central nervous system.
- The nerves that go through the whole body make up the peripheral nervous system.
The human brain is incredibly compact, weighing just 3 pounds. It has many folds and grooves, though. These give it the added surface area needed for storing the body’s important information.
The spinal cord is a long bundle of nerve tissue about 18 inches long and 1/2-inch thick. It extends from the lower part of the brain down through spine. Along the way, nerves branch out to the entire body.
The brain and the spinal cord are protected by bone: the brain by the bones of the skull, and the spinal cord by a set of ring-shaped bones called vertebrae. They’re both cushioned by layers of membranes called meninges and a special fluid called cerebrospinal fluid. This fluid helps protect the nerve tissue, keep it healthy, and remove waste products.