If I recall right, some learning resource on NHK said it’s used for g-column sounds that aren’t at the start of a word. But I read somewhere else more recently that it’s just part of the Tokyo dialect. I find it hard to remember to say the nasal g in the right moments, but I’m not sure whether it actually matters.
It’s also a part of Standard Japanese, the “official” Japanese of television news, etc (and other dialects as well). But no one will judge you for not using it.
I’ve met a lot of Japanese people from all over Japan, mostly young people, and I personally haven’t heard anyone pronounce the nasal g. If you watch television/dramas/anime/etc you’ll hear it from time to time, so it’s good to be able to recognize it. Also, if you take the JLPT, you will hear it in the listening part of the exam, so again, good to recognize it.
Like Leebo said, no one’s gonna judge you for not pronouncing it. From everything I’ve read, it’s growing out of use, and even news announcers aren’t as strict about it as they used to be (I remember reading that somewhere but I forgot where).
This was written by a native speaker on the subject, it might prove to be a useful resource:
I don’t even know what is that
In general, older people and news broadcasters tend to use the “nasal g” ([ŋ]), while younger people tend not to, so it also seems to be slowly “dying out”. But you’ll still hear it quite often for a long time probably. Note that this “nasal g” usually only appears in the middle of the word, not at the start.
From a study from 1941:
Here’s a pretty good, more detailed explanation with some interesting history:
It also depends on the region in Japan, the map is pretty interesting. Unfortunately i don’t know which year it is from.
Red is “standard hard” g, green is “nasal g” ([ŋ], though the map actually differentiates further)
Nice article, I haven’t seen it yet. But now I miss Kristen even more… For each two articles on Tofugu that I liked a lot, one was written by her.
Oh, I didn’t even realize that it was Kristen, I just linked it since there’s always a Tofugu article and nobody else mentioned it.