The Trinidad & Tobago midfielder said: "A little part of me thought that I might have been moving on in the New Year and I would have been disappointed if that had been the case.
"I had a wonderful time at Wolves and they have a great group of lads there and a good manager in Mick McCarthy. I hope they keep their form going for the rest of the season and can win promotion to the Premiership.
"But really I went to Wolves to get games, get my sharpness back and I always wanted to return to Sunderland.
"I'm delighted to be back here now. It was a surprise to be recalled but it is good to be back in the fold again and to know that I am still a part of the manager's plans."
He added: "I am very pleased to be back wearing the red and white stripes again. I want to be a part of things here at Sunderland and the manager knows that."