Kage Baker was thoroughly, blessedly diurnal. Given her druthers, she’d happily sleep in a bit in the mornings – but at need, she was up at dawn and as active as a lit sky rocket. Come sunset she began to slow; moonrise and she was drooping. By midnight, she was either asleep or so wired on stimulants to prevent it that she was audibly buzzing.

And once she went to sleep, she stayed that way. It took real effort to wake her from her sleep – earthquakes (if strong enough – she slept through several); midnight phone calls; screaming babies. Ordinary noises didn’t do it, though she was hard-wired to the sounds of telephones or unhappy children. But Kage was not one of the people to whom you could safely entrust the mid-watch on guard – your entire picket line, the cook and your best boots would have been stolen by morning, and she would never have stirred.

As I have whined interminably here (you are all so patient, Dear Readers) I am a chronic insomniac. Or used to be; lately, my sleep cycle is nothing so orderly as merely missing. It’s deranged. If it were the energy output of a generator, the lights would be going on and off constantly, and signaling aliens in Morse code between times. I can’t discern any pattern to it, and so I have pretty much given up – I’m trying to go with the flow, and see what emerges.

It appears that I am awake without remedy until I can’t stay awake any longer. Then I sleep like a hibernating groundhog until I can’t anymore. Then I wake up and am again helplessly conscious. The actual duration of the cycle is variable and I can’t figure out what it is … I’m just awake until I’m asleep, and then I’m asleep until I’m awake. I’ve pretty much given up worrying about it and am just trying to adjust.

Most people do have a sleep/wake pattern longer or shorter than our abitrary 24-hour clock cycle. It’s just that they can adjust it somewhat to fit the necessities of life. And usually they have to go live in a cave for a few weeks before their “natural” cycle asserts itself. Not me! I will now sleep through any amount, colour and pattern of lights; and I will be awake and thinking furiously in pitch darkness.

The Kindle helps. So does the computer. I can read, write, shoot zombies, all without giving a care or a fig for the hour on my Kit Kat Clock. That’s how I ended up awake at 4 AM (after 4 hours of sleep like a coma); reading about the more recent evolutionary changes in the human cerebrum and cerebellum, and sharing popcorn with the little black cat. I assume it was her, anyway – as she is black, she is invisible in the dark. I just handed down pieces of popcorn to the patch of velvet by my feet, and something took it and purred. Cats shouldn’t eat popcorn, of course. They are obligate carnivores. However, those are very big words and the little black cat doesn’t know big words. She just likes popcorn.

At any rate, I was awake. And now I find myself pondering the cerebellum – which contributes to sleep cycles – and how changes in it might have contributed to the unique, interior life of the mind that is believed to be a hall mark of crossing that final border into true humanity … maybe the Cro-magnons and Neanderthals had insomnia, too. Maybe they too stared into the tiny lights they conjured in the enveloping darkness, and handed treats down to invisible companions in the shadow …

Kage died of a tumour in her cerebellum. And even then, she never had insomnia. But I am pretty sure she was looking over my shoulder last night, nodding and thinking: There might be a story in this …