So that the reader can get more absorbed in the passage .
You can highlight and annotate things and put them in direct quotes if you are sealing to give this person credit or reference them in your writings. but otherwise while doing research you shouldn’t be to worried unless you are claiming it as your own work with going no credit
Noise is anything that might interfere with the communication
It is true that hallucinogens distort an individual's perceptions of reality.