Accents

Since the first two posts here were kind of long, I'll try a short anecdote for a change.

In a conversation with two German students today, the topic of regional accents came up. Like many German students, they spoke enough English to hold a conversation. However, they don't notice much of a difference between an American English and a British English accent, even though, as an American, I can tell the difference between the two in a second.

I found this strange at first, but then realized I'm not really that good at telling some regional German accents (with the exception of Bavarian and Swabian, which are more like dialects than accents) apart which are distinct to most German speakers. I have even more trouble with French, a language of which I know a small amount. I've been told that French spoken in the Provence has a strong accent compared to, say, French spoken in Paris, but I can't hear a difference. My hypothesis is that a person has to learn to tell accents apart by hearing people speak in other accents than their own; this ability doesn't come naturally. However, this still doesn't exactly explain why I'm readily able to tell a native speaker apart from someone who learned the language another way, in both English and German.