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for all the 🐝 lovers out there

Hey everyone! I started this blog today to spread love and knowledge about bees. Follow me @alicethebeevet if you want to help save the bees! More coming soon! 🐝

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This week I want to tell you about the case of Henry Molaison, the most well-studied amnesia case in history. It may be a long one but it’s definitely worth it so strap in.

Henry, who would later become known as ‘H.M.’, was your average American guy born in Manchester, Connecticut in 1926. At the age of seven, he got into an accident on his bicycle, hitting his head and causing brain damage. From then on he began suffering minor or partial seizures with the doctors diagnosing him with epilepsy. As time went on he grew older, and not long after his 16th birthday, his seizures started to become more severe. He began working on an assembly line at a factory but by the time he was 27 his seizures became so severe that even with medication he could no longer continue to lead a normal life.

In 1953, because of this, he was referred to a neurosurgeon called William Beecher Scoville. Scoville managed to determine (although I couldn’t find out how) that Henry’s epilepsy was coming from the ‘medial temporal lobes' on both sides of his brain and, due to how badly it affected his life, recommended surgical removal. This included the entirety of his hippocampus as well as most of the amygdala. Some other areas also died off later because of the surgery. At the time, very little was known about the brain and how it functioned. When the doctors and researchers took out these areas they had little idea of what other effects this may have on him.

Now, of course, you may already know what the hippocampus is known for and expect what is coming next. The researchers, however, did not. For Henry, the day of the surgery is the day his life stopped. He could remember his childhood, most everyone in his life, and a lot of information about the world around them. He could not, however, form any new memories from that point onwards. Someone could walk into the room and introduce themselves, walk out, and once they returned Henry would have no recollection of who they were. For him, every moment from then on in his mind took place directly after his surgery. Nobody had ever seen anything like it.

Scoville, the neurosurgeon, and his researching partner, Brenda Milner, began to study him immediately. They made him do hundreds and hundreds of memory tests, trying to pinpoint exactly where his memory was strong and where it was failing. Eventually, they realised there was some memory loss from the decade leading up to the surgery, getting worse the closer it got to it. His short-term memory, however, appeared to be working pretty well, but he could not store them to remember things later. The results of their studies were published to the world, a condition which was called and is still known as ‘anterograde amnesia’.

This revolutionised a large part of the field of neuroscience. Because the details of the loss of brain areas were known researchers could find out exactly how the hippocampus was involved in memory, and what types of memory other brain areas must have done instead. He showed, in particular, that he could still learn motor skills and remember them, that he had problems with sentence and language comprehension, and that his spatial awareness and memory was severely damaged. Researchers and scientists of all types flooded in from around the world to study the patient known as H.M. For the next five decades, he would spend the vast majority of his time undergoing these studies, and while researchers told him of how he could be revolutionizing medicine he could never remember it himself. He lived a long life, dying at the age of 82 in 2008 and donating his brain to science, providing even more research to continue on him after his death.

While it is easy to get caught up in the science of this case it’s actually a very sad story of a man named Henry, who went to doctors to seek help and it caused the end of his life as he knew it. He was always willing to be researched and consented every time, but ethically looking at it he could never remember all the years where that was all he did. While he may not have been outwardly suffering I doubt we can say that if Henry could have been aware of his situation then he wouldn’t have wanted to spend the vast majority of his life as a subject of scientific study. However, he should be remembered. What scientists did learn from him completely changed, and most importantly improved, our understanding of brain function. Moreover, others who came after him with their own neurological issues would receive better treatment because of what he went through.

So, to Henry Molaison, neurosciences most famous patient!

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Is there a scientifically proven cure for the hiccups?

Just want to give a quick shout out to SciShow as a YouTube channel because that’s what used to answer all my science questions when I was younger, and this was one of them! (Linked below).

So, as you might know, hiccups are caused by a spasm of your diaphragm (the bit of muscle under your lungs that helps them inflate/deflate). This causes you to take air in too quickly and your vocal folds in your throat to basically slam shut, making that weird ‘hic’ sound.

There is no guaranteed way to cure the hiccups, but there are ways to ‘trick’ your nervous system into stopping spasming. This essentially means distracting it. Swallowing a spoonful of sugar is a commonly used method, and this works because it’s quite difficult to swallow and confuses the ‘vagus nerve’ which controls a lot of the muscles in your torso. You can also increase the amount of carbon dioxide in your body by holding your breath/drinking water (more common cures) which forces your body to try and breathe normally to restore oxygen levels.

I’m actually a person that gets hiccups a lot and personally I used a mix of these two methods! I get a bottle (or glass) of water and take lots and lots of little sips giving myself no time to breathe in between. This distracts the vagus nerve through the constantly having to focus on using my throat muscles and also increases the amount of CO2 in my lungs. I would say works around 80% of the time.

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Why do some animals like cats and stuff have eyes that light up in the dark?

It's because they have a layer of tissue in their eyes (just behind the retina at the back of the eye) called the 'tapetum lucidum'. This is reflective meaning the light will bounce back off it and more will be absorbed by the 'photoreceptor', or light sensing, cells that are there. This helps them see much better at night than we do. The reflection of the light also means that they look as though they are glowing when you see them.

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Why do some animals like cats and stuff have eyes that light up in the dark?

It's because they have a layer of tissue in their eyes (just behind the retina at the back of the eye) called the 'tapetum lucidum'. This is reflective meaning the light will bounce back off it and more will be absorbed by the 'photoreceptor', or light sensing, cells that are there. This helps them see much better at night than we do. The reflection of the light also means that they look as though they are glowing when you see them.

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why is there a myth that bees shouldn't be able to fly???

Great question! For those who don’t know there’s a “fact” that it is impossible for a bee to fly according to the known laws of thermodynamics. While that might be true if you used the same equations we use for planes, it is very clearly false. Bees can fly. What’s happening here is if you used a plane aerodynamic equation, you would be assuming that, like a plane, a bee has a fixed wing that doesn’t move. However, bees move their wings in a long thin oval shape horizontal to their bodies, backwards and forwards, and they move up and down incredibly fast while doing so.

Bonus fun fact: When a bee that lives in a hive finds a good source of food, they point it out to the other bees by moving in an infinity or number 8 motion while waggling their stingers in the direction of the food.

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I’ve been a little MIA this week but I’m back for part 3 of oddball! This week we’re going to look at a 49-year-old Brazilian man who, after surviving a stroke, developed some strange personality changes.

The patient, named Mr. A, had high blood pressure, eventually leading to a blood vessel in his brain bursting. When this happens, the brain is cut off from oxygen which damages it (just like in last weeks post, although very different circumstances). Most commonly strokes are known to cause paralysis issues, loss of speech, etc. but emotional and behavioural changes are quite common too. The most common of these is depression, but there are other cases of people having uncontrollable laughter or crying.

Mr. A, however, developed something researchers the University of Rio de Janeiro later called ‘pathological generosity’. He would give money and food to children on the street, donate large sums to charity, generally give to anyone who would ask for it. While this might seem nice it completely upturned his life. He was unable to manage himself financially and had to leave his career where he previously work as a manager for a large corporation. This didn’t seem to bother him at all, however, and he was always in a good mood. When asked if he would like to go back to work he said he’d already worked enough in his life and now was the time to enjoy it.

The researchers carried out psychological evaluations on Mr. A but didn’t find any evidence of manic symptoms (like would be seen in bipolar disorder) or dementia. But what was happening in his brain? A scan showed that a number of different regions in his brain had a low blood supply, but not the area that was originally damaged. Instead, it was areas connected to it through neural pathways. Researchers believed that the subcortical region was responsible, which works to regulate our behaviours, put limits on us. Specifically, it was the ‘lentiform nuclei’, which form an important connection between the base of the brain and the cortex.

This was a particularly fascinating case for neuroscientists as it was the complete opposite of usual behavioural changes after a stroke, which include sociopathy and hoarding, and was not a result of any mental illness.

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Hey, how do massages work? Like you just rub someones body and they feel better???

Well, there’s actually nothing overly complicated about it. The physical action literally stretches and moves the muscle, forcing it to lengthen and relax. It removes the ‘knots’ you get in your muscle, which form when a muscle is used a lot in a stationary position (think bad shoulders/neck from sitting at a computer all day). This also increases the blood flow, giving the muscles more oxygen and essentially making those cells work better.

The fact massages are relaxing actually helps a lot too. It pushes your body into a deep relaxation response, lowering your blood pressure, reducing stress hormones, and, of course, relaxing our muscles. Massages generally can have really great side effects because of this, it’s basically forcing your body to heal itself (to some extent, of course).

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your other question about nerves got me thinking.. how are nerves reattached in surgery if they are severed?

Like I said in the last post if only the axon (the long body) of the nerve is damaged it will heal itself eventually (about 1mm a day). Surgically it’s a lot simpler than it seems, and it’s more about just attaching the two broken ends together, and then the body can usually do the rest (like stitching a wound). Usually this isn’t perfect and there will be some loss of sensation or tingling, especially for the first few months/years. Occasionally the nerves are just replaced from another area of the body, similarly to how a skin graft would work.

One cool futuristic idea is using 3D printing to help guide nerve repair. This has been tested on rats, where a healthy nerve is 3D printed, and then a silicone tube is made that fits it inside perfectly. The nerves are then severed and the tube is used to help guide the nerve as it recovers. Obviously, in humans in real life situations this would not work as you wouldn’t have a perfect 3D copy of the healthy nerve. However, you could make a catalogue of lots of different nerve shapes and pick out the one that fits the situation best.

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(potential tw for injury detail)

For the second week we’re going to look at a ~puzzling~ case of epilepsy.

Our patient of the week was a twenty-five-year-old man, a physical education student living in Germany. On a skiing holiday he was involved in a horrible skiing accident caused by an avalanche. Being buried under the snow he suffered a ruptured spleen and fractured ribs, but much worse he was deprived of oxygen for a full 15 minutes. Thankfully, a friend he was with manage to perfume CPR and save his life, but there were some side effects.

He would get muscle spams of his mouth when he tried to talk, and in his legs when he tried to walk. Because of this, he had to undergo some physiotherapy at the hospital. One day, weeks after his initial injury, he was waiting in the rehabilitation clinic and decided to pass the time by doing some Sudoku puzzles. When he did so his left arm started to spasm but, very oddly, as soon as he put the puzzle away the spasms stopped. After telling his doctors about this incident they decided to conduct a functional MRI scan to see if they could get to the root of the problem.

During this scan, the patient was told to solve a Sudoku puzzle, while researchers and doctors looked for any abnormal brain activity. They found that one part of his brain, called the right central parietal cortex, showed really high levels of activity. This particular area of the brain is known to be involved in processing visuo-spatial information, meaning it helps us with awareness of what’s around us and our navigation in the world. The reason this happened with Sudoku puzzles is that there is a spatial element to the puzzles (with different numbers going in different rows/columns/squares) and the patient himself would picture this mentally to solve them. Doing math calculations, for example, did not produce the same effect.

But how did his accident cause this, you might be asking? Well, when the patient was deprived of oxygen it caused some of the cells in his brain to be damaged or die. In particular, this affected neurons (brain cells that send signals) called U fibres in this part of the brain. These U fibres are inhibitory, meaning that they reduce the ‘signal strength’, and without them it meant the area of the brain that was damage was very overactive. When this happens in any area of the brain it can trigger seizures, which is essentially what any form of epilepsy is. Luckily, unlike people with photosensitive epilepsy, solving Sudoku puzzles is a much easier trigger to avoid, and the patient went on to be seizure-free for over five years.

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Insanely cool! I’d definitely never heard of this before.

Oooo heres one! What, in your opinion, are the coolest/most unique symbiotic relationships between animals?

I think most of the most interesting just because most people have never heard of it and it's truly bizarre is the symbiotic relationship between a salamander (Ambystoma maculatum) and salamander algae (Oophila amblystomatis).

The alga actually grows inside in the egg capsule of the salamander's eggs, and is not been found to grow anywhere else. They've also now been found to also grow within the actual cells of the salamander embryos.

The alga metabolises CO2 that is produced within the egg by the salamander embryo, via photosynthesis and converts it into O2. This makes it the first (and so far only) example of endosymbiosis in a vertebrate species.

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Tumblr Answertime

Just in case any of you didn't notice you can now go on Tumblr answertime to ask questions to NASA SPOCS. This is a program for higher education students who get to design experiments to send into space. They're going to be doing a live stream on the 3rd of June where they answer all of them. Thought any followers of this blog would probably be interested!

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I don't know if you've answered something like this before, but what's that thing where you suddenly shiver for no reason, and why does it happen?

Thank you in advance for answering!

I don’t think I’ve ever answered this before! First off, your body always shivers in response to something. Usually, that would be the cold, because shivering increases your temperature, or even through fear (think of a cat with its hair standing up). However there are other types though, such as in response to music playing, or looking at something in particular, or just randomly like you mentioned.

There’s not really a definite reason why they happen, apart from the fact they are tied to your emotions or cognition (thinking). Likely it has to do with a rush of dopamine release in your brain, which is why they’re more common if listening to music, or looking at a painting, etc. There is some evidence that your personality can also affect whether you will get them or not. Specifically, one scientific paper in 2007 showed that people with high ‘openness to experience’ (adventurous, try new things) are more likely to experience it.

Muscle twitches (rather than ‘the chills’ or a shiver) can also just happen at random, and these are called myoclonic jerks. Examples of these include twitches or hiccups, but they don’t always have a regular pattern. Sorry I couldn’t give a better answer!

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Liquid Glass?

I don’t know if I might be behind the times a little on this one but I just heard about it and thought it was a really cool use of science in everyday life. Liquid glass is pretty much what it sounds like, small particles of glass (silicon dioxide) suspended in a liquid. It’s a nano-coating first developed in the 80’s, and commercially available since the early 2000’s, which can be used to strengthen phone screens.

It can do this because on a microscopic level your phone screen isn’t all that flat, having lots of little bumps and rigids. The liquid glass, when spread on, can fill in these little gaps making the screen smoother, and therefore less likely to break. In fact, up to six times less likely to break. Being only 100mm thick it’s invisible to the human eye as well, meaning your phone can be protected while still in its ‘naked’ form.

It doesn’t need any glue to be able to stick as it forms weak bonds, called Van der Waals forces, with the glass already on your screen. Liquid glass is also super-phobic, meaning it repels both water and oil-based liquids, is very flexible, is acid and alkaline-resistant, and temperature-resistant. Essentially, a very cool material.

Had you all heard of it before? Do you know what else it’s used on?

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does muscle have nerves?

when you get cut and the nerve gets severed, does it reheal itself?

Muscles do have nerves! Signals are sent from your brain (or spinal cord) through these nerves which make your muscles tense or relax, letting you move.

To know about how damage to these nerves is repaired you first need to know the structure of the nerve. The important parts to focus on are the axon, which is what signals are sent down, and the myelin sheath. This is a fatty tissue that conducts electricity, letting the signals be sent faster. (note: this is a central nervous system neuron and the ones in your muscles are slightly different)

Most injuries won’t sever the nerve as the myelin sheath provides some protection. Instead, fibres inside the axon will break. Over time, the body will eventually be able to replace these fibres. Sometimes the ends of the neurons will die but they do eventually grow back as well. Severe wounds, however, can break the myelin sheath which does sever the nerve. When this happens, your body won’t naturally repair it and would need to be treated with surgery, potentially causing some paralysis.

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I know what video you’re on about, it’s very cool to look at but I’m sorry to say it’s actually digitally edited.

how do chameleons change color???

First of all, a really common misconception about chameleons is that they change colour to blend into their surroundings. Actually, they change colour to regulate their temperature, or to communicate to other chameleons.

But how is much more interesting. Pigments, compounds that produce colour such as melanin, play a part. Chameleons have a number of different pigments trapped in tiny sacs in skin cells called ‘chromatophores’. The chameleon can make these cells expand or contract which then changes their colour, and different coloured pigments are kept in different layers of skin.

However, there is more to the story. In between the different layers, chameleons have lots of tiny little crystals called ‘iridophores’. Essentially these work a bit like prisms in how they can split light and reflect certain colours. The colour it does reflect is determined by how far apart the crystals are. If close together they reflect only short wavelengths such as blue light, for example, while further apart reflects longer wavelengths producing red.

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Cute science is the best science.

A baby Aardvark and the strange teeth of their order “Tubulidentata”. Aardvarks are the sole living member of their mammalian order which includes another 15 or so creatures. They evolved shortly after the extinction of the dinosaurs and are evidently named for their strange tube like teeth.

Each tooth is made of thin, hexagonal, parallel tubes that have their own pulp canals. The teeth have no enamel coating and they grow constantly throughout their lives, being worn down by usage. They also only have teeth at the back of their jaws, which are molars. Oddly, baby Aardvarks grow regular mammalian Incisors and Canines at the front of the jaw that fall out during adolescence and never grow back.

The name Aardvark means “Earth Pig” in Afrikaans and they are commonly thought to be Anteaters due to their similar appearance and the fact that they can consume up to 50,000 ants a day. But in reality, they aren’t closely related to Anteaters at all, but share a close lineage with Elephants.

Aardvarks almost exclusively eat ants and termites, but they also eat a fruit that they share a symbiotic relationship with, known as the Aardvark Cucumber. The animal defecates the seeds near their burrows into the loose, rich soil allowing the seeds to grow much faster compared with normal soil. Also, the specific environment within the intestines of the animal increases the fertility, and thus the probability of the survival of the seeds.