Returning head coach Giuseppe Sannino has masterminded two wins from three games - following up a shock victory over Roma with last weekend's 3-1 success at Sampdoria - and Palermo are now within one point of making 17th place their own.
While Von Bergen admits recent triumphs will live long in the memories of Rosanero players and fans alike, he stressed just how fast they will become irrelevant if not followed up against Bologna on Sunday.
The Swiss told La Repubblica: "We proved we were still alive against Sampdoria and we have to confirm it on Sunday.
"If we go down on May 19 then no-one can take away what we did against Roma and Samp, but to make those wins count we have to save ourselves.
"When you win you see how the fans start to believe again and that's great. When we got back from Genoa we found a lot of people waiting outside the stadium at midnight.
"We have to take that kind of positive energy onto the pitch."
Andrea Dossena, Stefano Sorrentino, Abel Hernandez and Andrea Mantovani are injury concerns for Sannino.
"We've always believed in survival," Von Bergen added. "There were a lot of people who stopped believing after our string of defeats but that never happened to us.
"Today we have 27 points but that is not enough. We have won two games in a row but we still haven't achieved anything.
"There are still seven games left and all our remaining opponents are quality sides."
Bologna, meanwhile, are virtually assured of their place in the top flight having moved 10 points clear of the bottom three last weekend.
For Rossoblu boss Stefano Pioli, however, a 2-2 draw with Torino represented two valuable points dropped as Rolando Bianchi emerged from the bench to equalise for Il Toro at the death.
"We must stay focused despite this disappointment because we have to leave the prospect of relegation behind," he said.
"It is important to leave this bitterness behind and push on towards better performances."
Midfielders Diego Perez and Michele Pazienza are unlikely to feature due to injury at the Stadio Renzo Barbera.