Is sloth the same thing as torpor?
In Tibetan tradition torpor (Pali middha) is explained as heavy sleepiness, while sloth (Pali thina) is explained as laziness, lack of motivation.

So in case of sloth, you are not drowsy, just don't feel like striving. While in case of torpor, you kinda want to strive but can't, because your mind is so unwieldy.