Your brain’s ability to collect, connect, and create mosaics from these milliseconds-long impressions is the basis of every memory. By extension, it is the basis of you. This isn’t just metaphysical poetics. Every sensory experience triggers changes in the molecules of your neurons, reshaping the way they connect to one another. That means your brain is literally made of memories, and memories constantly remake your brain. This framework for memory dates back decades. And a sprawling new review published today in Neuron adds an even finer point: Memory exists because your brain’s molecules, cells, and synapses can tell time.
Defining memory is about as difficult as defining time. In general terms, memory is a change to a system that alters the way that system works in the future. “A typical memory is really just a reactivation of connections between different parts of your brain that were active at some previous time,” says neuroscientist Nikolay Kukushkin, coauthor of this paper. And all animals—along with many single-celled organisms—possess some sort of ability to learn from the past.
I hope, in the annotations and commentary below, I have added some context. But I also believe very firmly in the set of propositions that animated the project from the start: that the public does not appreciate the scale of climate risk; that this is in part because we have not spent enough time contemplating the scarier half of the distribution curve of possibilities, especially its brutal long tail, or the risks beyond sea-level rise; that there is journalistic and public-interest value in spreading the news from the scientific community, no matter how unnerving it may be; and that, when it comes to the challenge of climate change, public complacency is a far, far bigger problem than widespread fatalism — that many, many more people are not scared enough than are already “too scared.” In fact, I don’t even understand what “too scared” would mean. The science says climate change threatens nearly every aspect of human life on this planet, and that inaction will hasten the problems. In that context, I don’t think it’s a slur to call an article, or its writer, alarmist. I’ll accept that characterization. We should be alarmed.
Plague, famine, heat no human can survive. This is not science fiction but what scientists, when they’re not being cautious, fear could be our future.