Or, you might be looking for the 'buttons' in the top right corner under "USER INFO":
Hey, Snuffy/Bloggins/Whomever, you have 0 messages, 0 are new.
Total time logged in: 48 hours and 48 minutes.
Show unread posts since last visit. <--------(This is probably the one you want)
Show new replies to your posts.
June 07, 2004, 11:48:48