This is not a feature. You would have to modify the directory.php model in /jreviews/models. There's a getTree function there and you'd need to include the section description field in the query.
'Section.access AS `Section.access`',
'Section.description AS `Section.description`'
);
Then in the themes directory folder you can use the description as well. This is not trivial and you need to know what you are doing. I really can't go further into this.
