Vaughan: O'Neill has lifted atmosphere at Sunderland
Vaughan believes Martin O'Neill's arrival has had a positive impact and has praised his new manager's man-management skills.
"Training has been good and the lads have settled in well under the new regime," he explained on safc.com.
"The new manager is really easy to deal with. He's spent a bit of time with everyone getting to know us as individuals.
"It's nice to feel like he is interested in your situation and I think it definitely helps on the pitch."