Yes, I believe you can!
Although I'm not sure how, there is a midi instrument/effect in the instrument, effect or utilities options.
You will require a decent audio device so you can record the audio back into reason though.
I felt a bit silly putting four in!
I have not produced anything for possibly 3-4 years.
I don't even have my own computer anymore, these were made on my daughters laptop, and to top it off, the keys a-l only work when they want too.
I was bored one day and bought propeller heads new reason, and then checked to see what was happening on this site.
The length of the tracks was cut, as I don't think people want to listen to the intro-outro, they are of course needed for mixing.
Big up to all, as the tracks were the best set of tracks I've heard in these compos.