Saido Berahino's nerveless late penalty was enough to end the home side's 10-game wait for a win against a Newcastle side who lost defender Mathieu Debuchy to a straight red card.
Uncertaintly still swirls around The Hawthorns with caretaker-boss Keith Downing insisting he is not interested in taking the job full-time and urging the club to act quickly to appoint a permanent successor to the sacked Steve Clarke.
But Brunt maintains the mood in the home dressing room has remained buoyant in a stark contrast to reports which have suggested the Baggies are firmly in the grip of a relegation struggle.
Brunt told his club's official website: "It's a confidence boost for everyone. The boys have pulled together and we have turned a corner now. Hopefully we can start afresh in the new year.
"The belief we've had over the last couple of weeks has been unreal. Dean (Kiely) and Keith (Downing) have stepped in and they've done a great job. Hopefully we can get something in the cup and build on that."
Meanwhile Newcastle boss Alan Pardew insists his side's defeat will not change his plans for the January transfer window, with speculation once again mounting over the respective futures of Yohan Cabaye and Papiss Cisse.
Cabaye continues to be strongly linked with the likes of Manchester United and Paris St Germain while Cisse was sidelined again at The Hawthorns with Shola Ameobi favoured in attack.
To add to potential personnel problems for Pardew over the coming month, the club revealed Fabricio Coloccini is set to be ruled out for up to six week with injury, and Debuchy will be suspended for the next three games.
But Pardew insisted: "The result has not changed our thinking. We have our plans and we'll see what materialises."
Reiterating his position on Cabaye, who seemed certain to join Arsenal at the start of the season before a late change of heart kept him at St James's Park, Pardew added: "For us it is a situation where he is a Newcastle player. He's very happy with us and he is very important to us."