That isn't short-term memory
That's a well-trained long-term memory.
Seriously, anything that you can maintain for more than 30 seconds is long-term memory. Long-term memory varies in length. But there is no difference in kind between what it takes to remember something for 5 minutes and 10 years. There is a difference in kind between what it takes to remember something for 20 seconds and 5 minutes.
We know that these really are different in the brain because there are people who have lost their ability to lay down long-term memory. Short term memory still works for them. They can also learn new skills. (Apparently people tend to be amazed when they "know" that they can't, say, play piano but they actually have the skill and just don't remember it...)
Cheers,
Ben
