Gastrointestinal Peptides Vagal Afferent Synapses And Neural Mechanismsof Satiation10
Robert Ritter elaborated on information and ideas presented earlier byTimothy Moran and explored in more detail how GI peptides, CCK inparticular, provide the brain with information that contributes to theprocess of satiation and reduces food intake. He focused on CCK becausescientists know more about how it modulates vagal afferent activity comparedwith what is known about other GI peptides.
Studying The Social Context Of Eating Behavior
Dubé also was asked how population-level data, such as the softdrink consumption data that she presented, could be used to generatehypotheses about eating behavior and how better-quality population datacould be collected. She replied by emphasizing that the very rigorousstandard for collecting population data for epidemiological study needsto be applied in the study of food environments, accounting for samplingand other research methods. She noted that the soft drink data she usedin her analysis were predictions based on available private data andthat she and her research team used predicted rather than actual data inorder to derive population-level estimates and draw inferences at thepopulation level.
Here’s How Colours Really Affect Our Brain And Body
Exposure to light in the morning, and blue/green light in particular, prompts the release of the hormone cortisol which stimulates and wakes us, and inhibits the release…
- Why Colors Have Such A Great Impact on Us?
- How Different Colors Manipulate Us?
While animals have greater hearing and smelling senses, night vision, and even electricity waves perception, we humans rely too much on our eyes to understand the world around us. Colors may be powerful tools to bring up memories, make someone feel in a specific way or call to action. Without a doubt, the explanation about this is coded deep in our human beings. In nature, there are two groups of colors warm and cold. Most people associate warm colors with the day, springtime and summer. Such colors are all the shades that come out of yellow, red, and orange. And the cold spectrum reminds us of the night and winter. Their colors are purple and violet, blue, and grey, plus their many shades. Thus, warm colors make us feel lively, full of energy, while on the other hand, cold colors remind us of calmness.
Black and white
People perceive and see the world through colors. Companies use the colors through marketing to draw up clients. Anyway, they help us understand different situations in our life and provide us with the ability to express ourselves. All of this only because our minds are used to colors since birth. Author: Yoanna Borisova
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Things That Can Go Wrong With The Brain
Because the brain controls just about everything, when something goes wrong, its often serious and can affect many different parts of the body. Inherited diseases, brain disorders associated with mental illness, and head injuries can all affect the way the brain works and upset the daily activities of the rest of the body.
Here are some of the problems that can affect the brain:
Brain tumors. A tumor is an abnormal tissue growth in the brain. A tumor in the brain may grow slowly and produce few symptoms until it becomes large. Or a tumor can grow and spread rapidly, causing severe and quickly worsening symptoms.
Brain tumors can be benign or malignant. They usually grow in one place and may be curable through surgery if theyre located in a place where they can be removed without damaging the normal tissue near the tumor. A malignant tumor is cancerous and more likely to grow rapidly and spread.
Cerebral palsy. This condition is the result of a developmental defect or damage to the brain before or during a childs birth, or during the first few years of life. Cerebral palsy affects the motor areas of the brain. A person with cerebral palsy may have average intelligence or can have severe developmental delays or mental retardation.
Headaches. Of the many different types of headaches, some of the more common are:
Reviewed by: Yamini Durani, MDDate reviewed: October 2012
The Spinal Cord Transmits Signals To And From The Brain And Commands Reflexes
The spinal cord is an elongated cylinder of neuron cell bodies, bundles of axons and other cells, protected by connective tissue and bone. It connects to the brain at the medulla oblongata and runs down the vertebral column, the hollow tunnel enclosed within the vertebrae of the spine. The spinal cord is part of the central nervous system and serves as a kind of superhighway. Sensory information and motor commands travel up and down, heading to and from the brain. These signals speed in and out of the spinal cord via spinal nervesthe on-ramps and off-ramps that branch out to supply the limbs, torso, and pelvis. Some incoming signals demand a simple, immediate response. The spinal cord can shoot out a reflex command without bothering the brain.
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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.
Neurons May Look Different From One Another
Neurons come in a variety of shapes and sizes depending on where theyre located in the body and what theyre programmed to do. Sensory neurons have dendrites on both ends and are connected by a long axon that has a cell body in the middle. Motor neurons have a cell body on one end and dendrites on the other end, with a long axon in the middle.
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Contextual Influences On Eating Behavior11
Laurette Dubé considered the different levels of context within whichbrain-digestive system interactions operate. Specifically, she consideredhow higher-level brain systems and mental processes the fetal environment and lifelongprogramming parenting and other familial influences and the broadersocial, commercial, and cultural food environment can impact eatingbehavior.
What Does Pain Do To The Brain
When it experiences excessive activity in response to chronic pain signals, neurons in this region can die, causing this part of your brain to shrink. As a result, you can experience higher states of anxiety, fear, and worry as your prefrontal cortex becomes unable to manage these emotions properly.
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What Happens In The Nervous System When You Stub Your Toe
WHAT happens when you stub your toe? By watching the nervous system as it processes painful stimuli, American researchers think they have an answer. They have shown that nerve cells in rats’ spinal cords change shape in response to pain and then revert back to normal after the painful stimulus has been removed.
How The Brain Works
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.
Both the brain and the spinal cord are protected by bone: the brain by the bones of the skull, and the spinal cord by the set of ring-shaped bones called vertebrae that make up the spine. Theyre both cushioned by layers of membranes called meninges as well as a special fluid called cerebrospinal fluid. This fluid helps protect the nerve tissue, keep it healthy, and remove waste products.
The brain is made up of three main sections: the forebrain, the midbrain, and the hindbrain.
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Related Findings On The Effects Of Psilocybin
Psilocybin is a hallucinogenic drug naturally occurring in certain mushroom species. Like LSD, psilocybin primarily acts as a serotonin2A-receptor agonist . Presumably, its subjective effects are very similar to those of LSD . It is therefore likely that psilocybin induces neural alterations very similar to those of LSD. However, reliable data have yet to be found. Compared with LSD, psilocybin has been examined by means of neuroimaging for some time, the first human study having been undertaken in the 1990s . The group from London, who also conducted one of the LSD studies mentioned above, investigated comparable aspects of functional connectivity changes after psilocybin in 15 healthy subjects . The first study investigated connectivity between several resting state networks and reported widespread increases across several networks, in general accordance with findings obtained after LSD administration . However, as we have already pointed out elsewhere , agreements between these findings after psilocybin and alterations seen after LSD administration were quite limited. This raises the question about the specificity of the observed alterations for hallucinogenic drug effects. The second study investigated changes in global functional connectivity and found increased global connectivity in several regions, including the precuneus and the thalamus . Therefore, these latter findings are in relatively good agreement with alterations seen after LSD administration .
Does The Brain Stay Alive After A Person Dies
April 2019 marked a milestone for both the initiative and neuroscience research at large: BRAIN Initiative researcher Nenad Sestan, of the Yale School of Medicine, published a report in the journal Nature, revealing that his research team had restored circulation and some cellular functions to pig brains four hours after the animals’ deaths, Live Science previously reported. The results challenged the prevailing view that brain cells are suddenly and irreversibly damaged shortly after the heart stops beating. The researchers did not observe any signs of consciousness in the brains, nor were they trying to on the contrary, the researchers injected pig brains with chemicals that mimicked blood flow and also blocked neurons from firing. The researchers emphasized that they did not bring the pig brains back to life. They did, however, restore some of their cellular activity.
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Anatomy Of The Brain And Spine
Learn more about the anatomy and the functions of the brain and spine
- Information and support
- Anatomy of the brain and spine
The brain and spine are vital to keep the body alive and functioning. Everything we do depends on the messages that are sent from the brain, along the spinal cord and on to the rest of the body.
The Cellular Mechanisms By Which Gi Peptides Modulate Vagal Afferentactivity
Ritter elaborated on what Moran had discussed about CCK reducing foodintake through its effect on vagal afferent neurons. According toRitter, a vagal mode of action characterizes not only CCK but most otherGI peptides as well in fact, their ability to reduce food intake isattenuated or virtually abolished when the abdominal vagus nerve is cut.For ghrelin, however, the stimulatory effect on food intake is morecomplicated. According to Ritter, ghrelin appears to antagonize theexcitatory effects of some of the other GI peptides on vagal afferentfiring, although a role for the vagus in actually mediating the increasein food intake through ghrelin is doubtful.
All vagal afferents release glutamate, a neurotransmitter, in thehindbrain. Thus, not surprisingly in Ritter’s opinion,CCK-induced reduction of food intake has been shown to be sensitive toantagonism of glutamate receptors in the hindbrain. In fact, antagonismof NMDA-type glutamate receptorswith selective receptor antagonists injected directly into the hindbrainreverses or prevents reduction of food intake by exogenouslyadministered CCK .
An interesting feature of vagal afferent fibers, according to Ritter, istheir very quick release of all available neurotransmitters and failureover time. Susan Appleyard has shown that upon stimulation of vagalafferent inputs, postsynaptic cells fire but then fail however, theirfailure can be reversed by local application of CCK .
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Nervous System Development Across The Human Lifespan
As a species, humans have evolved a complex nervous system and brain over millions of years. Comparisons of our nervous systems with those of other animals, such as chimpanzees, show some similarities . Researchers can also use fossils to study the relationship between brain volume and human behavior over the course of evolutionary history. Homo habilis, for instance, a human ancestor living about 2 million years ago shows a larger brain volume than its own ancestors but far less than modern homo sapiens. The main difference between humans and other animals– in terms of brain development– is that humans have a much more developed frontal cortex .
Interestingly, a persons unique nervous system develops over the course of their lifespan in a way that resembles the evolution of nervous systems in animals across vast stretches of time. For example, the human nervous system begins developing even before a person is born. It begins as a simple bundle of tissue that forms into a tube and extends along the head-to-tail plane becoming the spinal cord and brain. 25 days into its development, the embryo has a distinct spinal cord, as well as hindbrain, midbrain and forebrain . What, exactly, is this nervous system that is developing and what does it do?
Innervation Of The Gi Tract
The GI tract is innervated both intrinsically and extrinsically. Theintrinsic, or enteric, nervous system is embedded in the wall of thedigestive tract and is localized primarily in the myenteric plexus andsubmucosal plexus.The enteric nervous system contributes to overall gastrointestinalmotility, nutrient handling, gastric acid secretion, and other functionswithin the GI tract . It is important to note, Moran observed, thatwhen external inputs are cut, that is, when the extrinsic system isdenervated, the enteric nervous system still functions and can regulateoverall GI functionnot in a normal, coordinated way, but in sucha way that there is ongoing digestive activity. Thus, the entericnervous system is not completely dependent on extrinsic input and canoperate in isolation.
Enteric neurons extend across the GI tract and are activated by thepresence of nutrients in what Moran described as a somewhatnutrient-specific manner, with different nutrients triggeringdifferent patterns of activity. Using c-fos, a stainable marker ofneural activity, researchers have demonstrated nutrient-inducedintrinsic neural activation under a variety of circumstances .Because the same neurons can also be activated by extrinsic activity,with stimulation of vagal afferent fibers producing similar c-fos activation, it isunclear whether nutrient-induced intrinsic effects are an altogetherlocal phenomenon or are dependent in part on stimulation activated bysignals from the brain .
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How To Calm An Overactive Sympathetic Nervous System
If an individual has an overactive SNS in times which are not considered dangerous, there are quick methods which can somewhat aid in calming down the SNS.
Taking deep breaths at a slow and steady pace, as well as various breathing exercises, are ways to encourage our parasympathetic nervous system to antagonize the SNS. This can be a quick way to help manage stress responses and decrease anxiety.
Similarly, practicing mindfulness is another method to actively prompt the body to rest, rejuvenate and regenerate, allowing a return to homeostasis.
For more serious cases of chronic stress, deep breathing may not be useful, so it is recommended to seek a doctorâs advice, who may recommend medical treatment or talking therapies to be able to combat the cause of the stress.
About the Author
Olivia Guy-Evans obtained her undergraduate degree in Educational Psychology at Edge Hill University in 2015. She then received her masterâs degree in Psychology of Education from the University of Bristol in 2019. Olivia has been working as a support worker for adults with learning disabilities in Bristol for the last four years.
How to reference this article:
How to reference this article:
Guy-Evans, O. .Sympathetic nervous system functions . Simply Psychology. https://www.simplypsychology.org/sympathetic-nervous-system.html
Biology Dictionary. . Sympathetic Nervous System. https://biologydictionary.net/sympathetic-nervous-system/
What Has The New Research Found
The latest research was led by Nick Spencer, a professor at Australias Flinders University. Spencers team studied mice using high-resolution video in combination with an analysis of electrical activity.
According to the study, published in the journal Communications Biology, how the ENS coordinates propulsion of food and drink along the gastrointestinal tract has been a major unresolved issue.
The paper describes how the ENS is far more complex than expected and considerably different from the mechanisms that underlie the propulsion of fluid along other muscle organs that have evolved without an intrinsic nervous system.
How is the World Economic Forum bringing data-driven healthcare to life?
The application of precision medicine to save and improve lives relies on good-quality, easily-accessible data on everything from our DNA to lifestyle and environmental factors. The opposite to a one-size-fits-all healthcare system, it has vast, untapped potential to transform the treatment and prediction of rare diseasesand disease in general.
But there is no global governance framework for such data and no common data portal. This is a problem that contributes to the premature deaths of hundreds of millions of rare-disease patients worldwide.
The project is a collaboration between entities in the UK , Australia , Canada , and the US .
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