What's the difference between English & Japanese parenthesis?

Question

I found this sentence while reading よだかの星:

よだかは、じっと目をつぶって考えました。（一たい僕は、なぜこうみんなにいやがられるのだろう。）

It seems pretty obvious that the parenthetical sentence is the Nightjar's internal monologue... but parenthesis aren't normally used like that in English
(English uses quotes or nothing for internal dialogue).
e.g.
The nightjar stopped to think, "Why am I hated by everyone like this?"
Why am I hated by everyone like this, the nightjar stopped to think.

And that got me thinking, (assuming my translation isn't way, way off...)
Are parenthesis () commonly used instead of 「」for internal dialogues in Japanese?
&
Are there any other notable differences between English & Japanese parenthesis?

Answer 1

Yes parentheses are used like this in novels. From Wikipedia 括弧:

小説等の文学作品やゲーム作品では、会話に表れない心中表現や外国人や動物のセリフの訳文であることを示すのに用いることがある。また、ゲーム作品においては、回想シーンやテレパシー（実際に喋っていない）等での会話に用いる事もある。

And "(?)" as in "ハードディスク(?)とメモリ" may be not very common in English text, although this is nonstandard in Japanese anyway. The remaining part of the explanation seems to be true both for English and Japanese parentheses, so I think these are the only significant difference.