Student or Learner
Scientists have made some important ......... about human brain recently.
Do we use discoveries or discovery here. Is the singular form wrong?
Generally speaking and in most cases "some" preceding a countable noun makes the noun plural. So "discoveries" is most correct.
But "discovery" can be correct too. If you say 'Scientists have made some important discovery about the human brain recently.', this "some" means (an)(one) unspecified or unknown discovery. (unknown to the speaker/writer)