NASA has made a charge to send humans to Mars by the 2030s. This is an aggressive goal when you think that a archetypal round trip will last anywhere amid three and six months and crews will be accepted to stay on the red planet for up to two years before all-embracing alignment allows for the return adventure home. It means that the astronauts have to live in bargain (micro) force for about three years – well beyond the accepted record of 438 connected days in space held by the Russian cosmonaut Valery Polyakov.

In the early days of space travel, scientists worked hard to figure out how to affected the force of force so that a rocket could ballista free of Earth’s pull in order to land humans on the Moon. Today, force charcoal at the top of the science agenda, but this time we’re more absorbed in how bargain force affects the astronauts’ health – abnormally their brains. After all, we’ve acquired to exist within Earth’s force (1 g), not in the airiness of space (0 g) or the microgravity of Mars (0.3 g).

So absolutely how does the human brain cope with microgravity? Poorly, in a abridge – although advice about this is limited. This is surprising, since we’re accustomed with astronauts’ faces acceptable red and aggrandized during airiness – a abnormality affectionately known as the “Charlie Brown effect,” or “puffy head bird legs syndrome.” This is due to fluid consisting mostly of blood (cells and plasma) and cerebrospinal fluid alive appear the head, causing them to have round, puffy faces and thinner legs.


These fluid shifts are also associated with space motion sickness, headaches and nausea. They have also, more recently, been linked to blurred vision due to a accession of burden as blood flow increases and the brain floats upward inside the skull – a action called visual crime and intracranial burden syndrome. Even though NASA considers this affection to be the top health risk for any mission to Mars, addition out what causes it and – an even tougher catechism – how to anticipate it, still charcoal a mystery.

So where does my analysis fit into this? Well, I think that assertive parts of the brain end up accepting way too much blood because nitric oxide – an airy atom which is usually amphibian around in the bloodstream – builds up in the bloodstream. This makes the arteries bartering the brain with blood relax so that they open up too much. As a result of this adamant surge in blood flow, the blood-brain barrier – the brain’s “shock absorber” – may become overwhelmed. This allows water to slowly build up (a action called oedema), causing brain abscess and an access in burden that can also be made worse due to limits in its arising capacity.

Think of it like a river overflowing its banks. The end result is that not enough oxygen gets to parts of the brain fast enough. This a big botheration that could explain why blurred vision occurs, as well as furnishings on other skills including astronauts’ cerebral activity (how they think, concentrate, reason and move).

A trip in the ‘vomit comet’

To work out whether my idea was right, we needed to test it. But rather than ask NASA for a trip to the moon, we able the bonds of Earth’s force by assuming airiness in a appropriate aeroplane nicknamed the “vomit comet”.

By aggressive and then dipping through the air, this plane performs up to 30 of these “parabolas” in a single flight to simulate the activity of weightlessness. They last only 30 abnormal and I must admit, it’s very addictive and you really do get a puffy face!

With all of the accessories deeply attached down, we took abstracts from eight volunteers who took a single flight every day for four days. We abstinent blood flow in altered arteries that supply the brain using a carriageable doppler ultrasound, which works by bouncing high-frequency sound waves off circulating red blood cells. We also abstinent nitric oxide levels in blood samples taken from the acquaint vein, as well as other airy molecules that included free radicals and brain-specific proteins (which reflect structural damage to the brain) that could tell us if the blood-brain barrier has been forced open.

Our antecedent allegation accepted what we anticipated. Nitric oxide levels added afterward again bouts of weightlessness, and this coincided with added blood flow, decidedly through arteries that supply the back of the brain. This forced the blood-brain barrier open, although there was no affirmation of structural brain damage.

We’re now planning on afterward these studies up with more abundant assessments of blood and fluid shifts in the brain using imaging techniques such as alluring resonance to affirm our findings. We’re also going to analyze the furnishings that countermeasures such as rubber assimilation trousers – which create a abrogating burden in the lower half of the body with the idea that they can help “suck” blood away from the astronaut’s brain – as well as drugs to annul the access in nitric oxide. But these allegation won’t just advance space travel – they can also accommodate admired advice as to why the “gravity” of exercise is good anesthetic for the brain and how it can assure adjoin dementia and stroke in later life.The Conversation

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