Siliconera reports that a Japanese Oita Prison is making use of Nintendo DS and its brain training games to help senior inmates battle dementia. The prison that has more than a fifth of its population over the age of 65 has developed a program that involves yoga, stretching exercises and playing Nintendo DS. The program was put in place in 2010 and is designed to keep the older inmates from developing dementia. As you can imagine an inmate suffering from dementia can be a risk for guards and other inmates and not the least to himself or herself.
There is no mention of how effective the voluntary program is, but it is nice to see the Nintendo DS is still being put to good use.