Is there a particular reason why the particle が is usually used when talking about mental states and sensations and not は?

Examples:

おなかが痛い

音が聞こえる

頭がおかしい

Xが好き

From my understanding (and correct me if I'm wrong) it would be either wrong or unnatural to use the particle は in these sentences and similar ones, and I'm wondering if there's some deep grammatical explanation for why is that?

Edit: I understand that が puts an emphasis on the thing it comes after, but my question is why is it that only when you talk about mental states you use が by default (as opposed to say talking about books or cats etc. which could be either, depending on the kind of sentence it is). In other words, why statements about mental states and sensations usually trigger this grammatical structure as opposed to other subjects?