The average modern woman can confidently add juggler to her CV, and holidays are a fine chance to hone one’s skills. In my case it is all about retaining a relic of my sanity while I try to work and keep the kids happy.

This inevitably involves allotting my darling children timed slots on our various digital devices.

My son’s screen of choice is the iPad, which he will happily play on to the point of near invisibility. This is dangerous. There’s me, thinking just one more email and before I know it an hour has passed and his eyes have turned to Minecraft-shaped blocks.

But how much time is OK? There are all kinds of numbers flying around – no more than one hour a day in one report and no more than four hours per day in another. And some reports suggest that teenagers are spending as much as 11 hours a day on “screens”.

Before you download an app to monitor your family digital usage let’s look at the evidence.

To begin with this concept of “screen time” has got to go. We humans are obsessed with lumping things together and it really isn’t helpful in this case. The way a child engages with a TV is very different to an iPad and different again from hoola hooping on the Wii (Shakira eat your heart out!).

The majority of scientific research is looking at digital technology and childhood obesity where “screen time” is an analogy for sitting still. So surely we are better off looking at the time our kids spend being active.

One of the problems with the idea that kids who spend lots of time playing games or watching TV are more likely to be fat is that you could sit and read a book for the same amount of time and be equally unhealthy.

I think we need a mental shift away from blaming technology towards thinking about what percentage of time our kids spend being active. The research supports this idea.

The other problem is that there are so many factors affecting a child’s health it is proving very difficult to tease out the actual impact of digital technology.

We also engage with technologies very differently. Sitting and watching TV is obviously different to playing on a games console. Playing on an iPad is different still because you are touching the screen directly with your hands. The level of engagement has a big impact on what happens in the brain.

One thing we know for sure is that using digital technologies changes the way neurones connect up in the brain. This isn’t necessarily a bad thing though – every time we learn something (riding a bike, playing tennis, reading or playing a new game) the wiring in our brain changes so you would expect the brain to change in response to digital technologies.

We really don’t know yet what the effects on this rewiring will be long term. The old saying “everything in moderation” is by far the safest bet when in comes to kids. A good balance of physical and digital activity will minimise the chance of harm in future.