Good question! Neither. I write whatever is on my mind, it changes day-to-day. It's sometimes logical, rational things, plans for the day or week or a project, and sometimes it's dream recall from the night before, or pennies that have dropped, sometimes it's stream-of-consciousness, nonsense, or just fiction. I'll usually shift between these and page 2-3 tend to be more 'out there' and get to the deeper stuff going on in my life. I don't set a timer, but the process generally takes 25-30 minutes on an average day.
The key is to write without editing and as much as possible, without stopping to think or read.
The key is to write without editing and as much as possible, without stopping to think or read.
I learnt about the practice in The Artist's Way about 3 years ago. I think this is the most up-to-date website about it: http://juliacameronlive.com/basic-tools/morning-pages/