Categorical judgements

Any ideas on how to set MediaLab for categorical judgements? I only want my participants to rate videos with a "yes/no" answer, ideally usign the arrow keys. I tried the "scale response" but it seems this way confines me to the numboard and specifically have to use keys #1 and #2. Any alternatives? Note: reponse has to be by keypress not mouse, as I'm looking at reponse latency too (but not to the millisecond).

In the next version of MediaLab, there will be a key mapping function so you'll be able to assign different keys to be used for the different options on a scale response. Until then though, you are limited to 1 and 2. One alternative would be to use a 9pt or 12pt scale and you could use the extremes.. such as 1 and 9 or F1 and F12 respectively. You can hide the scale by using top parameter e.g., (p12,t1000). This would give the illusion of a 2 pt categorical judgement. The only other current alternative would be to use a button box or to create a custom HTML item. The latter might be a good way to go if you or anyone in your lab knows some basic HTML.