The midfielder was a January deadline-day signing from Newcastle and will have a reunion with his former club on Friday night.
The 31-year-old has taken his time to get going at the City Ground, having made five appearances so far, but Cooper expects him to be important between now and the end of the season.
“We knew that when we signed Jonjo, the player that we were getting and maybe where else he could have gone as well,” Cooper said.
“So we’re looking forward with him, he’s settled in well. He’s probably a little bit feeling like all of us, really eager to get this whole thing together in terms of performances.
“But he’s shown good commitment to how we want to be and I have no doubt that the contribution over the run in will be a positive one.”
Forest welcome Newcastle to the City Ground without a win in their last five, which has seen their cushion above the drop zone cut to just two points.
There are plenty of teams below them in the table and Cooper says they have to take heart from that.
“It has been tight for a while and everyone wants to stay above that horrible dotted line,” Cooper added.
“We’ve been in a place where the gap is bigger than what it is at the moment, but we’ve never been away from it totally where it’s not even a talking point.
“We’ve never thought like that. You’re always a result or two away from it looking more positive or more negative.
“We’re just in the same situation where we’ve been for a while. With teams from 12th to bottom in it, we’ve got to do our best to be as high as we can in that group.
“At the moment there’s a handful of teams below us and I think we should take confidence from that and reassurance.
“We’re having to do something no-one has ever done before, in terms of putting the squad together and the amount of signings.
“While we’re going through this unique situation we’re in a place where we’ve shown that we can be in a fairly positive league position and that should give us confidence to keep going.”