Nintendo has spent much of the last two years reaping the benefits of testing people's brain power on its handheld DS platform. The Brain Training games, along with Big Brain Academy, have been some of the biggest selling titles of the past few years, and arguably Nintendo's most lucrative franchises right now.

However, now the company is turning its attention to your eyes, with the unveiling of Sight Training. It's a game based on the Brain Training template, where a series of short tests contribute to giving you an overall score. That score then determines your Eye Age. They've got a construction kit for all this stuff sitting somewhere, we just know it.

Again, they've wheeled out some professor to give the whole thing some gravitas, and again, the talk is that by training your eye it can improve your focus. It throws in the graphs and the daily exercises, but crucially, unlike Brain Training, it fails to make the activities themselves engaging.

That said, you can't get to them all at once, as you need to unlock them slowly over a period of time. Activities include a boxing mini-game where you need to hit boxing pads that move around the screen with your stylus, while table tennis requires you to move a bat around in order to return a ball. Not all the activities are sport-centric, but they're all resoundingly simple and there are few you'll actively be waiting to play.

What puzzled us about a good number of activities was what it was they were testing. Reaction speed proved to be more crucial in many of the games we were presented with, and while there's some babble-science in the need to follow things around a screen with your eyes, if you can't move the stylus quickly enough your eyes will end up on zimmer frames anyway, according to the game. Yet it's really hand-eye coordination rather than sight that's being tested in most cases.

Of course, in the cold light of day, Brain Training itself is no classic game, and isn't short of a few problems of its own. But it did have enough within it and its sequel to compel you to return to it on a regular basis. Too much of Sight Training either struck us as annoying or puzzling (for the wrong reasons), though, and that's a real discourager when it comes to repeat visits.

Granted, it's only £20, and granted, it's not the worst of the casual game purchases Nintendo is offering, and it is ultimately harmless. But it's borderline useless, too.

A just-about-passable casual game, but this ain't no Brain Training, and it's not going to please your optician particularly, either.