To be honest, my motivation for posting it here was to see how long until someone starts working on a site based on it.

I have to admit, negative 7 days is sooner than I expected :p

Actually I wrote my first n-back test close to two years ago, but for myself. The biggest reason why I wanted to make a web version is because of all these brain games popping up, made by people who don't know what they're talking about. This thing is for real.

I'm also working on subitization test variants, but that's much more familiar.

Since you've trained with n-back (for two years!):

Did it improve your fluid intelligence?

How has it affected you personally?

Haha, back then I wasn't really into database applications and built it just to experience it. That's how I know that 2-back is fairly easy and 3-back isn't, but beyond that I can't answer you (yet).

I gave my dad a 3-back test, on which he did surprisingly well, and he said, "oh, that's easy, all you have to do is concentrate." Indeed, a big portion of it is attention.

I started sketching the data structures and the user interface as soon as I saw it on reddit a few hours ago.

But, I'm pretty glad someone else is already working on it. I have finals this week.

I guess you will announce your beta here on YC once you have something. Very interested.

A simple n-back variant is live as of this morning but my submission didn't last long... I'm replying to all the responses in this thread. Again, it's a simple implementation, but FYI, http://cognitivefun.net/test/4

What did you do to combat the effect of that "dull jobs numb the mind" study that was on here last week? (http://news.bbc.co.uk/2/hi/science/nature/7358863.stm)

I don't think I could stay interested in your n-back test for a whole 20 minutes at a time...

Good point. I also don't think anybody would play brain games for very long at a time. But then, such apps are highly motivation-dependent. There is a thing about learning rate and conscious effort, which is a much more difficult problem.

Tell us when you're done? And do you need help with coding?

As in my other reply, I'm not going to be quite "done" but a simple, working n-back test is here: http://cognitivefun.net/test/4

Won't be "done" in a while, because it's part of a larger work in progress, but I should be able to show something soon. I just started learning ActionScript, but cogsci programs aren't hard to write... but who knows, I look forward to criticism, which I expect much.

I want to log on now!

FYI (or, FY fun) I uploaded a simple n-back test here http://cognitivefun.net/test/4

Submitted to HN but it didn't last and I don't want to spam :)

Can't wait to try it! Get cracking! :)

Hey thanks, it's probably real easy for you to implement, but if you don't feel like writing your own, here's the one I was working on: http://cognitivefun.net/test/4

I submitted it here but it didn't last and I don't want to spam :)

I look forward to trying it out!

Thanks, I submitted earlier today but it didn't make FP. See this thread if you're interested: http://news.ycombinator.com/item?id=179580