This study...

...scares me.

http://researchnews.osu.edu/archive/exptaking.htm

Why?

Because it is going to be more ammunition for those who think all fiction should be suitable for a home-schooled six-year-old.

It also, however, gives useful information. For example, first person is more immersive than third person, and that's a tool writers can use either to increase or reduce the degree to which the reader identifies with the character.

Giving out information early may also reduce immersion...especially if its information that makes the character different from the reader. So, this is why spending half your first chapter describing your MC is 'bad'.

As writers, we want people to get into our characters' heads. But we may not want them to get into those heads too far, especially when writing certain kinds of horror.

I would like to see a much larger study that cross-references 'wanting to act like the character' with overall personality traits of the reader.