In one of my third (and final) year university lectures last week, we were being taught about MRI (Magnetic Resonance Imaging) and our lecturer wanted to demonstrate the sheer complexity of the brain. She explained that it is easy to over simplify the brain when describing it in terms of it’s regions or in terms of neurons. A lot of psychology is concerned with pinpointing certain areas that correlate with certain functions or behaviours. But the reality is that the brain is way more complicated than that. The brain is a series of connections and pathways that strengthen and weaken and some stop working altogether (this is also a simplification). Throughout my degree, I’ve been thinking I had a good understanding of the scale and complexity of the brain until I saw the video that my lecturer showed us.
(Needs to be watched in HD)
This is a journey through a mouse’s Somatosensory cortex. A tiny portion of the mouse’s 1mm thick cortex.
Green: Thy1HYFP (Layer 5B Neuron
Subset 35% of total neurons)
•Each red synapse contains about 100,000 protein
•Six million synapses in the Assue volume shown
•At least one hundred billion synapses in the whole mouse brain
…and the human brain is of course much bigger and has hundred of trillions of synapses.
I won’t go into how they took these images as I don’t even understand it fully but if you’d like to read the paper the reference is-
Micheva, K.D.,Busse, B.L.,Weiler, N.C., O’Rourke, N., Smith, S.J, (2010). Single synapse analysis of a diverse synapse population: Proteomic imaging methods and markers. Neuron 68:639
That might give you an idea of the complexity we are dealing with here. It certainly ‘blew my mind’ as it were and also it got me thinking and daydreaming philosophically for the rest of the lecture…
The brain is sort of like the Universe isn’t it? Each subject is at opposite ends of the spectrum: micro science and macro science but they are similar in that they have that scale of complexity that gives you a headache when you try to comprehend it.
I just think that picture is a beautiful example of how complex and amazing we all are!
Note to self: Stop thinking about the Universe when you should be thinking about fMRI