will expand all branches of the hierarchy.
will collapse the hierarchy and show only the goal and the first level of elements (threats).
You can also expand/collapse sections of the hierarchy by clicking the same icons at the left of the threat node.
When the Auto-Redraw box is checked, clicking on the name of any element will not only expand the branches below that element but will automatically contract the branches in other parts of the hierarchy. This is useful to be able to focus on a part of the hierarchy, see all of its ancestries, but not be distracted from details in other parts of the hierarchy.