Every time I think of the medieval majesty of Mont Saint Michel I don't hear polyphonic choirs or Debussy's La Mer, I hear "Hop, Skip & Jump!" played on a synthesizer and sung by a middle-aged woman who ought to have known better.

And the reason is that memories of our last holiday in Brittany were ruined forever by one of those awful kiddy tapes. You know the kind I mean. Gullible parents buy them by the handful in the naive hope that a car resounding to "We All Live in a Yellow Submaree-een!" will blind our children to the fact that it's a nine-hour drive to the gite in question.

Children's tapes are a growth market, but a growth market in the unfortunate way that condoms are a growth market. We don't actually like them per se, but until something that does the job better comes along we are stuck with them. Make no mistake, this diet of relentless jollity does do the trick. Five minutes of "Old MacDonald Had a Farm!" and the average infant appears drugged up to the eardrums.

But the awful question remains: what these tunes are doing to you, the adult? Your holiday memories are poisoned by nauseous nursery rhymes and emasculated pop tunes. Remember, you are sitting in the front, dangerously exposed to the speakers with their radioactive thumpa-ding, thumpa-ding. You are not allowed to talk in case a single synthetic note of jollity is missed in the back. And you are slowly having your brain turned to jelly by track after track of saccharine syncopation. This is music that makes Mary Poppins sound like Mahler. What is its effect on the average sentient being?

In our house we have labelled the children's tapes Brain Death I, Brain Death II etc and try very hard to ration them. But the problem is that on a long journey the choice is simple. You can have fights in the back, endless threats of wees or vomit and ineffectual games of I- Spy, or you can plump for a silence broken only by "Hop, Skip & Jump!" Yet all technology exacts a grim price. You try stringing a sentence together after a five-hour drive to the Lake District after "Ee Ay Ee Ay O!" or arriving coherent in Cornwall with "a Moo Moo Here and a Moo Moo There".

The brain has gone.