Why can’t neurons just form physical connections as in reticulate theory instead of using neurotransmitters?



why do they do the extra work to make neurotransmitters, convert electrical impulses into chemical then have neurotransmitters bind and then conversion into electrical again? Couldn’t they just connect with each other like other cells form a tissue as the reticulate theory suggested? Are there any advantages to this extra effort or is it just another lack of efficiency?

In: Biology

You’re asking why evolution did something the way it did, and you’re probably never going to have an answer to that.

Evolution is the culmination of millions of years of *what worked*. Thousands of generations of putting things together in different ways, breaking them apart and doing it differently. What was deemed valuable was kept while anything that didn’t withstand the brutal test of natural selection was discarded from the gene pool.

Reticulate theory was one attempt to explain something based on incomplete knowledge, but the best we had at that time. There are countless things that we can think of that don’t make sense evolutionarily, but the bottom line is that evolution doesn’t have a reason. Only what works, and what doesn’t. Our brains developed that way because that’s what worked.

A few thousand years down the line, our brains might look completely different as evolution still continues.

With neurotranmitters you have much more potential for regulation at each junction. You can regulate the amount of a NT that is released, how quickly it is taken up, you can regulate number of the receiving receptors, and auto receptors can also regulate the neuronal “temperature”. And since each nerve cell has a nucleus with a copy of our DNA genes can be turned on and off the level of each individual neuron if needed to increase or decrease the production of all the receptors and ion channels in each neuronal cell wall. So it’s much more flexible arrangement since you have a mini brain (our DNA) in each neuron constantly adapting to changing local conditions as well as responding to input from other neurons.

neurotransmitters stick around for a while in which the cell doesn’t have to keep retransmitting. they’re also only released when enough electric impulses build up, which creates a way to regulate when a specific signal is transmitted