• Question: How do brains work??

    Asked by cheese2000 to Kate, Mark U, Tess, Yue, Faye, Martin, Mus, Pete on 1 May 2012.
    • Photo: Pete Etchells

      Pete Etchells answered on 1 May 2012:


      That is an incredibly good question, and it’s something that neuroscientists and psychologists spend a lot of time trying to answer! At a very basic level, the brain is like any other organ in the body, in that it consists of cells that are fed oxygen and glucose via blood vessels, and is connected to the rest of the body via the nervous system. Different parts of the brain have different roles, and work in different ways. For example, the “amygdala” is involved in emotional processing, particularly for fearful things. The way it works is by sensing how much carbon dioxide is in your bloodstream (if there’s lots, it will cause the pH of your blood to become more acidic), which it uses to check whether you’re suffocating or not – if you’ve got lots of carbon dioxide in your bloodstream, you might not be breathing and taking in oxygen properly. That kickstarts a fear response, which is supposed to help get you out of the threatening situation you’re in. Other areas, such as those that are involved in vision, take information from the eyes (which you get when light hits the back of your eye and gets converted into an electrical signal) and use it to see what patterns of lightness and darkness you are seeing. If the patterns are changing and moving, we can sense those changes and interpret them as moving shapes. Obviously, it gets a bit more complicated than that, but that’s the basic idea!

      There’s a big question in science, which is how we get from the brain as we know it (as a bunch of cells working together) to a thinking, conscious human being. That’s a really tough question, and we’re still working on an answer to that one!

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