Can you teach an old brain new tricks?

For the past four days, I've been playing "Dr Kawashima's Brain Training" on Nintendo DS. The idea is to get your grey matter fit by doing daily written and spoken exercises (involving words, numbers, colours and movement) - 'til it reaches the optimum "brain age" of 20. Mine started at 66. The next day it went down to 36. Then I realised my DS clock was 12 hours out (stupid 24-hour time!), wiped the slate and began again. My new starting brain age was 43. Today, I reduced it to 32. My real age is 34.

Note: The program's handwriting/voice analysis is far from perfect. Most of my "mistakes" have come from it misinterpreting what I've written/said - in particular, the number "5" and the word "yellow". However, if this helps me scribble and speak more clearly, then it's a good thing. And what do you expect from a $40 (Australian) cartridge?