Happy Valentine’s Day to my lovely, wonderful, amazing followers 💕 I’m hoping this day brings you joy and the encouragement to treat yourself (regardless of relationship status). Here is my favourite medblr valentine. With love, Tayla 💉🌹
In vertebrates, the eyeballs are direct extensions of the brain; that is, they evolved after the brain, and are literally unimpeded access to the cerebellum and cerebrum. Because of this, many ocular tumors or injuries can be far more dangerous to the brain than growths or injuries on any other part of the skull.
Anatome ex omnium veterum recentiorumque observationibus. Thomas Bartholin, 1673.
OKAY SO I HEAR A LOT OF PEOPLE GET CONFUSED ABOUT ALL THESE WORDS AND TERMS FOR TRANSFORMERS (because we, as a fandom, like to use fancy words for our robots, we have literally reached subculture status guys we have our own dialect congratulations) AND DON’T KNOW WHAT TO USE FOR WHAT SO BECAUSE I TOO SUFFER I WILL HELP YOU
IF YOU KNOW OTHERS THAT ARE NOT LISTED HERE FEEL FREE TO ADD THEM.
Going to be covering nerves and synapses this week so here’s a recap!
Soma (cell body) contains the nucleus which produces RNA to support cell functions, + organelles surrounding the nucleus which are mostly made of up endoplasmic reticulum. Supports and maintains the functioning of the neuron.
Dendrites - cellular extensions with many branches ‘dendritic tree’. majority of input occurs via the dendritic spine. The sum of all excitatory (neuron fires) or inhibitory (prevents firing) signals determines whether the neuron fires or not. If firing the action potential is transmitted down the axon.
Axon - fine, cable-like projection that can extend thousands of times the diameter of the soma in length. The axon carries nerve signals away from the soma (and also carries some types of information back to it). Can undergo branching - communication with target cells.
Axon hillock - where the axon emerges from the soma. the part of the neuron that has the greatest density of voltage-dependent sodium channels - therefore the most easily excited part of the neuron and the spike initiation zone for the axon - most negative action potential threshold. Can also receive input from other neurons.
Axon terminal where neurotransmitters are released into the synaptic cleft to signal the next neuron
Myelin is a fatty material that wraps around axons and increases the speed of electrical transmission between neurons. It is broken up by nodes of Ranvier, between which electrical impulses jump. Myelin is produced by schwann cells in the PNS and oligodendrocytes in the CNS.
Classes of neurons
Sensory neurons bring information into the CNS so it can be processed.
Motor neurons get information from other neurons and convey commands to muscles, organs and glands.
Interneurons,found only in the CNS, connect one neuron to another.
Types of neuron
Multipolar neurons have one axon and many dendritic branches. These carry signals from the central nervous system to other parts of the body eg muscles and glands.
Unipolar neurons are also known as sensory neurons. They have one axon and one dendrite with branches. Pass signals from the outside of the body, such as touch, along to the central nervous system.
Bipolar neurons have one axon and one dendrite branch. They pass signals from one neuron to the next inside the central nervous system.
Pyramidal neurons have one axon and two main dendrite branches. These cells pass signals inside the brain and tell the muscles to move.
Purkinje neurons are found in the cerebellum, controlling balance, coordination, and timing of actions. They have one axon and a dense and complicated dendrite arrangement.
Purkinje cell Professor M Häusser, Sarah Rieubland and Arnd Roth, UCL Winner of the Wellcome Image Awards, 2015. “Scanning electron micrograph of tree-like branches (dendritic tree) spreading out from a particular type of nerve cell (Purkinje cell, or neurone) found in the brain. The finger-like projections in this elaborate network act like tiny sensors, picking up information and passing on messages to help control and coordinate muscle movement. This particular neurone is from the cerebellar cortex in a rat brain.”
How the neuroscience of tickling can help you control your tickling response
Why can’t you tickle yourself? Your brain (or more specifically, your cerebellum) can predict how sensations will feel based on your own movements, so isn’t surprised when you tickle yourself. It suppresses the tickle response.
So to combat the tickly feeling caused by other people tickling you, cover their hand with yours. Your brain can then make predictions about how it’s going to feel, and doesn’t produce the tickle response.
So #20 for andreil. I literally love angst but you can do whatever
okay so i know that i literally just did an “Andrew gets hurt during a game” and i also know that “Neil getting hurt at a game” is sooooooo overdone but like…… you don’t understand how much of a slut i am for Neil getting hurt at a game
that being said, i took a different approach to it. don’t be mad at me
#20 “Something’s clearly wrong.”
never been so quiet. Never mind the sounds of machines blurring into white noise in
the background. Never mind Andrew’s own heart rushing blood past his ears in a
rhythm Andrew would give anything not to hear.
number eighteen striker, Neil Josten, just took a hard hit against the wall.
He… he doesn’t appear to be moving. Something’s clearly wrong. Can we call… ah,
yes, the referees are taking an executive move and calling the game to a pause.”
Andrew starts to
count off Neil’s injuries – again – because it’s better than hearing that
announcer’s voice repeat in his head one more time. Broken ulna, dislocated and
then relocated shoulder, severe sprain of his left ankle, heavy bruising, and
brain swelling that led to an induced coma.
Each breath Neil
takes sounds like it might be his last, but each beat of his heart brings him back.
ugh i read her tweet and immediately i was all 'CHRIST JOANNE PLEASE STOP TALKING'
LIKE ?!?!?!?!?!?!?!?!?!?!!?? i don’t mean to be rude but ??? what’s the point ?????????? how about you actually sincerely talk about these characters and your motivations for writing the way you did instead of superficial tweets cringing about one (1) death a year ?????? especially severus whose death actually had narrative impact and closure and resolution ??????? UNLIKE SIRIUS WHOSE DEATH COULD HAVE SO EASILY BEEN AVOIDED ?????????? WHOSE ENTIRE LIFE WAS RIDDLED WITH MISERY AND SUFFERING AND WHO COULD HAVE GIVEN SO MUCH MORE TO THE WORLD TO THE FIGHT TO HIS GODSON TO THE FEW PEOPLE HE HAD LEFT WHO TRULY KNEW HIM FOR WHO HE WAS ??????????? HOW ABOUT YOU TALK ABOUT THE IMPACT OF REMUS AND TONKS’ DEATHS ON TEDDY’S UPBRINGING ??????? HOW THEIR SACRIFICE AFFECTS THE WORLD HE WAS BORN INTO AND IS LIVING IN NOW ??????????? IM NOT HERE FOR FLIPPANT APOLOGY TWEETS IM HERE TO TALK ABOUT MY KIDS
A new study by scientists at McGill University and the University of Zurich shows a direct link between metabolism in brain cells and their ability to signal information. The research may explain why the seizures of many epilepsy patients can be controlled by a specially formulated diet.
(Image caption: Neurons in the cerebellum. Credit: Bowie Lab/McGill University)
The findings, published Jan. 16 in Nature Communications, reveal that metabolism controls the processes that inhibit brain activity, such as that involved in convulsions. The study uncovers a link between how brain cells make energy and how the same cells signal information – processes that neuroscientists have often assumed to be distinct and separate.
“Inhibition in the brain is commonly targeted in clinical practice,” notes Derek Bowie, Canada Research Chair in Receptor Pharmacology at McGill and corresponding author of the study. “For example, drugs that alleviate anxiety, induce anesthesia, or even control epilepsy work by strengthening brain inhibition. These pharmacological approaches can have their drawbacks, since patients often complain of unpleasant side effects.”
The experiments showed an unexpected link between how the mitochondria of brain cells make energy and how the same cells signal information. Brain cells couple these two independent functions by using small chemical messengers, called reactive oxygen species (or ROS), that are normally associated with signaling cell death. While ROS are known to have roles in diseases of aging, such as Alzheimer’s and Parkinson’s, the new study shows they also play important roles in the healthy brain.
The findings emerged from an ongoing collaboration between Prof. Bowie’s laboratory in McGill’s Department of Pharmacology and Therapeutics and a research team headed by Dr. Jean-Marc Fritschy, Professor of Pharmacology at the University of Zurich and current director of the Neuroscience Center Zurich (ZNZ). The researchers have the longer term aim of trying to understand why the seizures of many epilepsy patients – especially young children – can be treated with a high-fat, low-carbohydrate diet known as the ketogenic diet.
The idea that diet can control seizures was noticed as far back as ancient Greece, during periods of fasting. From the 1920s until the 1950s, the ketogenic diet was widely used to treat epilepsy patients. With the introduction of anticonvulsant drugs in the 1950s, the dietary approach fell out of favour with doctors. But because anticonvulsant drugs don’t work for 20% to 30% of patients, there has been a resurgence in use of the ketogenic diet.
“Since our study shows that brain cells have their own means to strengthen inhibition,” explains Prof Bowie, “our work points to potentially new ways in which to control a number of important neurological conditions including epilepsy.”