There's absolutely no way I can post a screen recording of this, as it's random and intermittent. I'm sorry I can't be more helpful here, but this only occurs when Designer is open with a PSD open and it happens throughout my OS. But I cannot reproduce it on demand. I've opened up Activity Monitor and haven't seen anything there *while I'm looking.* It's been happening since I installed App Store updates, including Designer.
I'm also not sure how a screen recording would convey that what appears on screen lags vs input on my keyboard. As I described, I type or enter keys, and randomly, intermittently it lags on screen by a second or two.