There's a little-known and decidedly average George Romero movie called Bruiser which, despite turning rubbish and hysterical at the end, has a creepy and intriguing premise. In it, Jason Flemyng plays a successful young marketing exec who wakes up one day to discover his face has inexplicably transformed into a smooth, white, featureless mask. He stands horrified in front of the mirror, trying to remove it but failing because it's fused to his head. He has literally become a blank.

That's the best bit of the film. After that it all goes a bit daft, as Flemyng's newfound anonymity sends him doolally and he runs around Los Angeles killing people left right and centre (mainly centre) until you just don't care any more. I'd have preferred him to stand weeping in front of the mirror for the remaining 90 minutes because I found that bit exceptionally creepy. And you know why? Because I can relate to it, that's why. Thanks for asking.

I could relate to it not because I've got a smooth, featureless face - sadly, it's more like a lumpy relief map charting myriad disappointments - but because in the past few months I've grown increasingly concerned that deep inside, underneath, in my heart, at my core, in my bones, within the very centre of my soul, lurks a terrifying, all-consuming, awful, echoing blankness.

Just to be clear, this is not the same thing as depression, which would manifest itself as an actively negative mindset. Rather it's an absence of any definable mood whatsoever. It's not like glancing at the glass of water and seeing it as half-empty; more like glancing at the glass of water and seeing it as half-full, but shrugging indifferently and staring at the wall instead of running around giggling and setting off party poppers. And to be fair, vacant indifference is the only sane reaction to a mere glass of water in the first place. It's hard to muster much enthusiasm or despair either way. Which leaping great cretin at the Department of Psychological Metaphor decided your opinion vis-a-vis a glass of water should be the barometer of character anyhow? If you want to find out who's a pessimist and who's an optimist, don't faff around filling tumblers - water's a precious resource, for Christ's sake. Just ask them. Or issue them a form with OPTIMIST and PESSIMIST printed on it, and see which box they tick. It's not rocket science.

Anyway, back to my thudding personal blankness. It's probably a bonus. On the one hand, I take absolutely no pride whatsoever in whatever meagre professional achievements I can muster, take little interest in anything outside work and am essentially just a blinking, shuffling mannequin watching events in his life merely drift past like underwhelming prizes on the Generation Game conveyor belt. And on the other, I just don't give a shit. It's a win-win situation. Or it would be, if I had any concept of "winning" in the first place.

Apparently this condition is known as "anhedonia" - the inability to derive any pleasure from things that would normally be considered pleasurable. Hand someone truly anhedonic a slice of chocolate cake, and at best they'll think, "Hmm, my tastebuds indicate this cake is delicious," rather than simply enjoying it. They subject it to Spock-like analysis, swallow it, shrug, and then crap it out a few hours later, wearing a neutral, unchanging expression throughout. Well, that's me, that is.

And it's hard to see what the cure might be. If you've fallen out of love with life - not to the point of actually disliking it, you understand, but to such a degree that you merely tolerate rather than welcome each passing day - it's surely impossible to get the spark back. Any suggestions? Religious epiphanies and extreme sports are out. And I could do without raising a family, thanks: that looks like an almighty pain in the arse and to be honest I couldn't be bothered. I'd immerse myself in a hobby but they all look so pointless. You might as well sit alone in a shed counting numbers. I've tried cultivating a passion for the arts but that didn't work either. I mean, I quite like plays, live music, exhibitions, museums and paintings, but not enough to spend more than 25 minutes journeying to see them. Reading's all right, but be honest - turning the pages isn't ultimately worth the effort. Perhaps serial killing would help. Yeah. That'd give everything a welcome bit of edge. Although I'm prepared to believe even that gets boring surprisingly quickly: within two weeks I'd be yawning my way through yet another humdrum strangling.

Still, it could be worse. Having listlessly Googled anhedonia, I see it's related to a hilarious spin-off condition called "ejaculatory anhedonia". Apparently it mainly affects men, and as the name suggests, the unfortunate few who suffer from it are incapable of deriving any pleasure whatsoever from orgasms. They make a bit of mess while staring impassively into the middle distance, and that's it. Like the human equivalent of a pushdown soap-dispenser. Now that would be depressing. Ah, well.

This week Charlie read The Tiger That Isn't: "A startlingly interesting book about statistics. Yes, statistics. Honestly, it makes them interesting. It does. But don't take my miserable word for it, go and pick up a copy and read it your stinking self."