Work on the inside

And let the outside fall into place.

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Feeling spontaneous

One of the ways to think about the brain (no pun intended) is like a circuit diagram.

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Activity is generated by the firing of populations of neurons, for example, in response to a sensory stimulus. What I learned recently is that spontaneous patterns of activity also occur, which are thought to be related to mental imagery (among other things).

Could spontaneous activity relate to thoughts…?

Thought experiment #2

What would time be like if it travelled backwards?

If we travelled backwards in time, would we unlearn the future?

Does memory depend on time?

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‘The Persistence of Memory’ by Salvador Dalí

Say it was possible. All our thoughts would’ve already happened so we would have no choice but to relive them without any free will, which implies some sort of observer that is separate from our thoughts, and also timeless…

What is time, anyway? Isn’t it just the evolution of a system? Or the growth of a plant?

Why do things grow and not ‘ungrow’?

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Time seems to represent some certainty about the past and an uncertain future.

If the Universe wants to reduce uncertainty, maybe that’s why time travels forward…?

Connection

Why isn’t the brain fully connected?

i.e. why are there gaps between synapses: 

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Don’t be too alarmed by this image, just notice the gap between the two cells. You might imagine that neurons communicate via electrical signals and whilst there are electrical synapses in the brain, chemical synapses (pictured above) are more common. The thing is that chemical synapses are electrical in a way because they move charges around.

How?

Neurotransmitter (for example, serotonin) is in a synaptic vesicle that fuses with the membrane of the pre-synaptic cell. In English? Its in a container that fuses with the wall of the pre-synaptic cell.

This allows the neurotransmitter to be released into the gap.

The neurotransmitter itself doesn’t actually go into the post-synaptic cell but binds to ‘receptors’, some of which allow ions (aka charged particles) to pass into the post-synaptic cell. This changes the overall charge of the post-synaptic cell and if enough charge gets in, it can trigger an ‘action potential’ – the cell fires and we have communication.

If these gaps didn’t exist, then the brain would (probably?) be uniformly charged. So the difference in charges might be able to explain why we don’t experience a ‘flat’ reality but instead one filled with a plethora of sights and sounds, feelings and emotions…?

LTP

Long-term potentiation (LTP) is defined as the strengthening of synapses based on recent patterns of activity i.e. learning and memory. This video highlights the fascinating mechanisms behind synaptic strengthening, once again demonstrating the remarkable function of our nervous system.