swithing windows in 3 pane view

When in 3 pane view and selecting a group in the database window (far left) is it possible to use a keystroke to get to window 2 (top left) and select a file or is a mouse click needed. Like the functionality of the view option to the left of 3 pane view on the toolbar, but still with the visable data of 3 pane view.

Ctrl-Tab and Shift-Ctrl-Tab can be used in most views/windows to move the focus.