onsdag 28 mars 2012

Under the skin pt 1 - BRAAIINS!

"I want a doctor to take a picture so I can look at you from inside aswell"

- The Vapors - Turning Japanese

I wanted to share some awesome pictures on what goes on under our skin. I find it fascinating to see what goes on inside of us! I am one of those who has "really looked at my hands" as they say - I find the fact that we all have skeletons inside us and that it is mostly dark inside us amazing.

Imagine, inside your tummy right now there's no light - or at least almost no light. Your intestines are working away, squeezing and pushing and juicing - all in darkness. Same goes for your heart, pumping tirelessly away in darkness. It's only when a surgeon puts a light in you or open you up that they will see the light. We are all dark inside, literally. (Except for Xorn who has a star for a brain.)

Brains - Valeria Petkova

Hedvigs brain
Sebastians brain
These are our brains, mine is the top and Sebastians the lower. The pictures were taken in a fMRI (functional magnetic resonance imaging) machine (->). 

Difference between brains
As you can see there is a difference between the brains of myself and Sebastian. This is probably mostly due to where the "slice is cut" so to speak. The difference in size and location of the cerebellum (the thing that looks like a cauliflower in the lower back) is probably not only due to slicing, that's just the way our brains are.

Our understanding of the brain
The brain is an amazing organ and we don't really understand it. In popular science and news reports scientists are often portrayed as knowing exactly what parts do what and that isn't really true. They have some fairly good estimations about where things mostly occur, but not much exact knowledge.
But one thing seems to be clear: the size of the brain has nothing to do with intelligence - it is rather how we connect and use the neurons that matters.
In our first years we lose up to half of our neural connections. We do away with synapses that we have no need for and this is a good thing - we need to be effective not large. Our brain goes through very drastic changes and we all seem to end up with slightly different strategies and solutions for doing the same tasks.

If you wanna look more at the brain and its parts visit "The Secret Life Of The Brain".

Why we have these pictures
We participated in an fMRI-experiment at the Karolinska institute in the fall of 2009. It was a part of my friend Valerias dissertation. I didn't know her at the time. I just saw posters at the university where they were looking for subjects for a study of "out of the body experiences". We thought it sounded pretty sweet so we signed up. Scientists in the making as we are we couldn't refuse to be part of such an epic study.

When the experiment was over they sent us a jpg-image of our brain. To be honest, we did get a sum of money too but I would have done it for the picture alone. I'm very happy to have it.

She met my good friend Gerard later and they became a couple. That's how I got to know her, months after she had done the experiment on me. They are two of the sharpest and nicest people I know. The world of interesting, sensible and nice people seems to be quite small.

Valerias study - making someone believe they are a doll
Her work is very interesting and concerns how we can perceive things as a part of our body even though they clearly aren't (perceptual and neural underpinnings of body ownership). They were trying to fool our brains with illusions that made it seem that a plastic doll was our body. If you're interested then read samples from the three articles they published.

Rubber Hand Illusion.
Picture from
The EmotionMachin-blog
Body ownership illusions
The classical example of this is the Rubber Hand Illusion, see youtube vid here.
The basic idea of body ownership illusions is to present the subject with a fake body part and let them see it being poked at the same time as the actual body part, that is out of sight, is being poked. The brain might (this doesn't work on everybody) assume that the fake body part belongs to the body because of the connection between seeing it being poked and the sensation of being poked at the same place.
My summary won't do this justice by far, I apologize Valeria!

What is so amazing with Valeria et als studies is that it's not just the hand but the entire body (minus the head) that is being faked. Quite awesome.

(At her phd defence she was asked if this could help cure racism, experiencing someone else's body as one's own :).)

The Ehrsson lab has the statement How do we recognise that limbs are a part of our body, and why do we feel that our self is located in the body. I means the epicosity of that statement is over 9 000!!

It's the same lab that was in Swedish news about fooling people that they had legs the size of barbie's legs. See youtube-vide here(!).

I hope you enjoyed looking
under the skin with me ^^!
I enjoyed spending this time with you,
see you around my little lemondrops.

"Turning japanese
I think I'm turning japanese
I really think so... "
Petkova, V.I., Björnsdotter M., Gentile G., Jonsson T., Li T.Q., & Ehrsson H.H. From part to whole-body ownership in the multisensory brain. Current Biology(2011) 21 1-5. PDF

Petkova, V.I. Ehrsson, H.H. If I were you: perceptual illusion of body swapping. PLoS One (2008), 3(12):e3832, Epub 2008 Dec 3 PDF

Petkova, V.I., & Ehrsson, H. H. Body self-perception. McGraw-Hill 2010 Yearbook of Science & Technology, McGraw-Hill Professional, New York (2010), 50-53 PDF

Petkova V.I., Khoshnevis, M. and Ehrsson, H.H., The perspective matters! Multisensory integration in ego-centric reference frames determines full body ownership. Front. Psychology (2011), 2:35 PDF

1 kommentar:

  1. Good brain there Hed.

    This might be interesting


    Paradigm shift in brain science is from left to right side, from cognition to emotion


    am reading his latest book now