We can try to break it down a little. Work notifications are not very exciting, so it probably doesn't give us a dopamine hit, however the notifications could be stressful if they are always about work and timelines. Study might be beneficial, it really depends on if it is a reminder or wants us to perform an action. Play varies widely, from a notification that a friend is or wants to play a game, to a developer has posted their weekly digest of what's been happening, these tend to give us dopamine as well as they can be interesting to learn about what's happening.