Frank's side sit second in the Championship after Saturday's come-from-behind 2-1 victory against Stoke.
Jacob Brown scored after just 27 seconds to give the visitors the lead but Vitaly Janelt equalised before Ivan Toney's 25th goal of the season secured victory and left Frank confident his side were back on track.
"In all seasons but especially this one, every team will go through a dip at a certain stage, but it's the ones that can handle it best that will be successful," he said.
"In the second half we went from level five to level nine. We were quicker moving forward, we took the initiative, and we had a much bigger mentality and attitude."
Frank hailed moments of brilliance from his two goalscorers and paid tribute to the club's coaching staff for Toney becoming the third striker in successive seasons to hit the 25-goal mark.
"Ivan wants to be better every day and he knows instinctively what he wants to do in those situations. It is down to him but also the work behind the scenes," he said.
Defeats for Watford and Swansea left the Bees with a three-point cushion to the teams below them in the battle for automatic promotion.
And now Frank and his team can turn their attention to leaders Norwich, who they face on Wednesday.
"That will be a very good game between two very good teams and I'm looking forward to it," he said.
Stoke boss Michael O'Neill hailed the clinical eye for goal of Toney as the difference between the teams.
"We had chances to go ahead and we have to take those like Toney took his," the former Northern Ireland boss said.
"He has proved there is not anyone better than him in this league. It's a great finish and good anticipation and that's what separates us in this game.
"In this league you need someone who is going to get into double figures and they have done a great job here and have replaced one prolific goalscorer with another."
O'Neill was pleased with his side's response to a midweek defeat at Barnsley, but admitted: "It seems like we're taking a couple of steps forward and then a couple back, but we don't want to be a team that settles for a comfortable position in the league.
"We lost to a good team that's challenging for automatic promotion so it would have been a big result to come here and win.
"In the first half we were very good and solid and made it difficult for them and looked comfortable, but in the second half we have to give credit to the opposition. They have a lot to play for but it took a good goal to swing it back in their favour.
"We didn't anticipate we would gain promotion this year but we wanted to challenge for the top six. As well as we've competed against teams above us, we've come up rather short. We don't want to end up with nothing to play for."