As Aiden, interacti with the chair first, then move through the wall on your intial right to reach the hall. You can find a [BLUE ORB] here on the left side, although you can't travel any further than this. Enter Nathan's office by switching back to Jodie.
Inside the office there are several optional things you can do, such as grabbing a book on alpha waves from the bookshelves, inspecting the photograph and the Christmas orb on the desk, or checking out Nathan's degrees on the wall.
The conversation options (Yes, No, Shrug, Silent) don't matter one bit. The only answers that have a minor gameplay consequence are when you're asked to draw Aiden (you'll have to do so) and whether he can do something (interact with an object in the room).