An oddly recurrent story – maybe a recurrent nightmare – in recent years is the one about the cinema accidentally showing “age-inappropriate” trailers at a children’s matinee. The upshot, if reports are to be believed, is terror and confusion: last Saturday, a young audience who came for Peppa Pig were shown glimpses of the forthcoming superhero-horror film Brightburn. Incidentally, it always seems to be a horror trailer – never a Fifty Shades marathon or an Irvine Welsh adaptation, which would add a lot of unwelcome words to the playground vocabulary.

I have a lot of sympathy with parents who expected a morning of benevolent primary-colour tedium, then had to deal with acute distress. I suspect the effect is exacerbated by the fact that trailers always tease a more frightening film than is actually delivered, and give young minds space to imagine far more appalling follow-up scenes than the finished movie will provide. Binge-watch horror trailers and you’ll notice a thrum of sinister music and sound effects, a shadowed and claustrophobic screen-space, random innocents wandering into tense situations, and the cruel smiles or blank masks of monstrous villains. No nuance, no comic relief, no sympathy, no social content, no gradual build-up and sudden release of tension, not much story – just jolts of fear-making.

‘I’d happily sit through hours of Waterloo or Cromwell just for precious minutes of a coming attractions trail for Blood on Satan’s Claw (above) or The Beast in the Cellar.’ Photograph: Tigon/RGA

In 1971 or so, too young to see horror films in the cinema, I relished the rare horror trailers screened with A certificate films. I’d happily sit through hours of Waterloo or Cromwell just for precious minutes of a trail for Blood on Satan’s Claw or The Beast in the Cellar, or the delirious (and wholly misleading) trailer for The Blood Beast Terror, which promises an unthinkably indescribable fiend (though the film itself just trots out Benedict Cumberbatch’s mum as a ratty giant moth). I was even happy with the milk marketing board’s cinema ad showing Vincent Price chugging a pinta on the set of The Abominable Dr Phibes, just for the glimpses of an X-certificate rat attack I thought I’d never be old enough to see in its full gory glory. One of the most telling lines of film criticism is Time Out’s review of the 1977 Suspiria, which said Dario Argento’s symphony of terror was “what horror movies seemed like when you were too young to get in to see them.”

What terrifies children isn’t just the stuff designed to scare. In The Wizard of Oz, for example, you get the witch but also the comedy lion – and even though cackling evil is dispelled at the end, the incidentals offer nightmare fodder: the tree with a human face, the winged monkeys, even the horse of a different colour. As Tim Burton or Guillermo del Toro – both jumpy kids who have grown up to love monsters – have shown, the world of an imaginative child is full of wonders and terrors, and if you strip out the latter by insisting on a diet of just Peppa Pig you risk raising a generation unable to cope with the slightest trauma.

I was a child in the 1960s and 70s – and there’s still a thriving industry in recalling the media horrors I was exposed to, from those public service information films (“I am the spirit of dark and lonely water” earned Donald Pleasence his horror immortality well before Halloween) to the crab claw or living mannequin cliff-hanger endings of Doctor Who (the opening trill of Delia Derbyshire’s end credits theme still makes me shudder with pleasing fright). I was afflicted with all manner of nightmares, set off by trivial prompts – not just things that set out to be spooky, but from random stuff like an eerie song Rolf Harris warbled on a TV show. The night terrors only stopped when I was 11 – which, not coincidentally, was when I stayed up late to watch Bela Lugosi as Dracula on television and transformed overnight into a horror movie fan.

Since then, as a critic and novelist, I’ve been chasing that dragon – trying to find again the fear, the perfect cosmic awe, that horror films are in your mind before you actually see one.

• Kim Newman is a novelist, critic and broadcaster