If you are reading this, congratulations! You have a brain! Now, when you think of your brain and the nervous system, you probably only think of neurons as the one’s doing the work. What you may not know is that glial cells, another cell type associated with the nervous system, are quite important.
Traditionally, glial cells were thought only to be support cells, hence their moniker “glial,” which means “glue.” While they do perform mundane functions such as extracellular pH moderation, structural support, and nutrient deposition, glial cells have also been not only to change the signal from neuron to neuron, but also to communicate within their own network.
This profound change to our understanding of these cells has led to a rapid growth in the field of glial cell signalling. While the details of exactly how glial cells change the voltages of the neuronal membranes are a bit too esoteric for this moderate post, feel free to ask me. Suffice it say that even in my own modest research into glial biology at the lizard neuromuscular junction, we found that glial cells were important in modifying neuronal signalling in response to extracellular signalling events. That is to say, glial cells talk to the neuron and get it to alter the message it sends.
If I can find this occurring in the relatively isolated neuronal network of a neuromuscular junction (in which only a few glial cells are present) imagine their importance in the brain! There could be a whole “glial signalling network” adding another layer to the already massively complex signalling network which we call the human mind. What if these cells could help us understand the “hard problem,” or how consciousness arises? In any event, I hope that when considering your brain and the nervous system, you now understand that neurons, while critical, are not the only players in the game of neurotransmission.