To be able to dream, or at least be able to remember my dreams if I actually am having them. I used to be able to remember my dreams pretty vividly right after I woke up and I could tell when I was having them. Now, nothing.
I am having pretty big dreams. I know it because sometimes I don't get out of the effect after I wake up. But I forgot after 5 minutes or so. Today I woke up, and I remembered initially. It was some huge legendary tale or something, or it felt like it. But I woke up, and knew I would forgot. Maybe I should write it down so I won't forget it.
And I used to dream like that too. I'd wake up remembering the dream initially and then gradually it would fade away if I didn't write it down. There would be times I would wake up right from my dreams, it was incredibly jarring. Now... it's just a blank slate, like I don't even have the inkling that I dreamt something or a vague impression, just nothingness.