Two seconds forward, one second back. You move the slice of pizza toward your mouth, and right before you bite it moves back a bit and you’ve got to do it again. You bite, chew, start to swallow, then have to swallow again.
Would your brain adjust to this kind of existence, or would every action take great focus? Speaking certainly would. Language would probably evolve to a short staccato so you could be sure not to be cut off mid word by the time jump. But, since no one forgets anything, you wouldn’t have to repeat yourself during the repeated second. Unless you were making a recording..
In this world, recording music, or playing it, would be almost impossible. But games would be very interesting, since you could act on what you saw happen the first time through that second… but so could your opponent. Playing games against a computer, though, would give humans an advantage, since the computer could only do the same thing over and over. Unless.. it was a conscious computer…