Well Sami. The solution is not always complete satisfactoty.
1. To do that with 1.9 version you can use groups and groupings: http://docs.moodle.org/20/en/What_is_the_difference_between_groups_and_groupings%3F. The problem is that only same activities allow this;
2. you can make one metacourse with several child courses, each one for each Learning Style (I NEVER try it). You assign your students to each course.
faq: http://docs.moodle.org/20/en/Groups_FAQ
3. Someone told me that in MOODLE 2.0 its easier to make what you want, but I am not sure. I only use moodle 1.9 until now; next year I will start to use it.
4. The issue here is that MOODLE philosophy is constructivism and not cognitivism.
Good work for you!