Last week, as part of an Easter holiday day out, I took my daughters to the Twist Museum up in London.

The museum describes itself as a ‘home of illusions’, and it’s a fascinating hour or so of trompe-l’oeils and assorted artists and scientists playing with your sense of perception.

My personal favourite was an infinity mirror room with slanting floor, ceiling and sides.

A couple of minutes in there and your brain slowly started to scramble.

Such illusions can offer more than a fun afternoon out, however. On the drive back from London, the M3 was clogged up with holiday traffic and my phone offered one of those alternative routes that though purportedly quicker, ends up being increasingly complicated.

Driving through one village, I slammed the brakes on at the site of a small child standing dangerously close to the edge of the road. When I caught my breath, I realised that the child was no such thing, but a bollard painted to look like a small boy.

These ‘child bollards’ have popped up around the country in recent years, as an innovative road safety measure to encourage drivers to slow down.

They’ve had mixed results – local residents tend to like the lower speeds, but less so the creations, halfway between an Antony Gormley statue and something from a horror movie.

Persuading people to cut their speed when driving is an ongoing battle. Last week, Robert Jenrick, the government minister, was banned for six months for being caught driving almost 30mph over the speed limit.

As a senior a minister in the Home Office, he perhaps ought to have been a bit better at upholding the law, but he’s far from alone in putting his foot down.

If fines and hard-hitting advertising campaigns don’t change people’s behaviour, then what does? Those creepy child bollards are one attempt at a different tactic.

Another similar but less scary approach is to paint 3D zebra crossings on the road.

Trialled in India and Iceland among others, these optical illusions make the crossing look like it is floating, again causing bewildered drivers to slow down.

Or maybe rather than punishing or tricking drivers, the answer to changing people’s behaviour is to be a bit nicer to them?

Instead of the stick approach, this week it was announced that French councils are trialling rewarding drivers for not speeding, rather than just punishing those who do.

Under this scheme, first attempted in Spain, traffic lights turn green for those driving under the speed limit, and stick on red for those going too fast.

Early evidence suggests the idea works, with traffic slowing by 5-10mph in one case study. Could a similar scheme be successful here?