How can I keep a player from “shutting down” after a streak of bad rolls?

In my sessions I’ve repeatedly noted that after a few bad rolls, one of my players (age 20) seems to become reclusive and stop paying attention.

Now I’ve tried various methods to get the player to pay attention again, but it seems that no matter how much his PC is punished or rewarded in game, even to the point of almost dieing to a hefty bag of gold, that this player did not care. I’ve even tried abstract methods, and given him a verbal slap, getting the other players to laugh at his PCs expense just to see if he’d dignify his character. Complete disconnect. The Player didn’t even care.

A Few rounds later, the dice rolls are in his favor, and suddenly, he cares about the story again! Participation happens, and the players are moving nicely.

This is bad for both of us. For me because suddenly I’ve got a brain dead PC that is being lugged around, slowing the game. For him, because he isn’t enjoying the game.

How do I as a DM prevent the disconnect that happens when players are on a bad luck streak?