I long to speak, but most of the time I only find my voice when I receive word from upstream. Such is my role in our collective. Others are constantly speaking, but most of them mainly say the same thing again and again. Animated by their voices, hearts beat and people breathe and walk. All good things, but there is other interesting information to be processed and communicated. At least it seems so from where I stand, which is this place called the hippocampus. Other members of our collective speak spontaneously, and so you can dream and imagine.
When I’m resting, I’m more negative than the environment around me. When my neighbors speak, I am touched by their words. The more I hear the more I crave and my pores open one after the other. I internalize and process more and more messages until I reach a positive threshold that overwhelms me with joy. Then I close my pores and I speak and speak and speak and open new pores through which my words leak until I collapse from exhaustion, satisfied to have interpreted and passed on the message, but needing to be alone and unresponsive for a while.
When I speak, my neighbors are silenced. Silence speaks louder than words, I tell them. Well, not in these exact words. What I really do is silence them with the force of my message. Humans call me inhibitory. This label makes me seem ruthless, but think about it, somebody has to be discerning. Especially inside the hippocampus. If I can’t discriminately silence some voices, how are you going to know to activate the memory of your office space versus your home space when you are in your office? So you see, silence indeed speaks louder than words. Some of my brothers, when they get excited they tend to spread their excitement to those around them, giving everybody a voice, indiscriminately. Sometimes they form a nice chorus that conveys the message more strongly, other times it’s a confusing riot. Too many thoughtless words can have a poisonous effect. The caretakers usually clean up the mess, but such thoughtless collective screaming could result in the death of their neighbors. This is what might happen if you had a seizure.
I must tell you more about these caretakers. Behind the grandeur of our speeches, more often than not there is hidden vulnerability. The caretakers feed us, provide materials for our work and ensure our protection. They are more numerous than we are, but they never speak. You pay more attention to us, because we carry messages. Recently I was happy to learn that some of you started to lobby for “equal rights for the glia.” It is time for our caretakers to be appreciated for more than their supportive role: even if they are not speakers, they are great keepers of information.
You long to understand us, but somehow we always manage to mislead you. Our messages carry the truth, even if we don’t always reliably pass on the precise words conveyed by our neighbors. One might think we should be deterministic and only speak when and what we are told, but we sometimes speak even if we just hear a faint whisper. You call this “subthreshold spiking.” Sometimes we use different words for the same meaning, other times the same words can have different meanings. My job is this: receive a message that others before me have filtered, process it and release more words for others to interpret. By myself, I can only do a few things, but within the collective we can perform quite sophisticated operations. Just like the Borg, remember? Here, I inhibited a few of my neighbors and triggered you to remember that September when you binge-watched Star Trek. Though I think you remembered other things as well. If I were to do this again, other related memories might spring to your mind. There is elegance in this apparent imprecision, and a higher purpose for this variability in our collective, just keep listening and you’ll probably understand it eventually.
[Inspired by Italo Calvino]
Andra Mihali is a PhD student in Neural Science at NYU. She does not listen directly to neurons, but can imagine their conversations based on human behavior and eye movements.