Derby County were “paralysed by fear” during their Championship loss at home to fellow strugglers Blackburn Rovers.
County led for a minute before conceding twice in four minutes to lose 2-1 and extend their winless streak to six matches in the league.
The Rams are in the bottom three, one point above bottom side Wigan, with just one league win all season.
“In the first half we looked as though we were paralysed with fear,” Pearson told BBC Radio Derby.
“We have a group which undoubtedly at the moment are not living up to the expectations externally, certainly not living up to the expectations internally and that’s my responsibility because I’m the manager,” added former Leicester City manager Pearson, who took over at the iPro Stadium in the summer.
“If we don’t get the basics out there and we don’t get the level of commitment to the game out there, it remains a very tough ask of us to get the performances which warrant points.
“Given what happened, we are exactly where we should be in the league. We got what we deserved and that’s the bottom line.”
Pearson continued: “I can’t keep hoping that players are going to bring their best games to the table week in week out, and then not do it, so I might have to start making changes.
“If that means introducing some of the younger players then so be it, but ultimately it’s about getting a team on the field that want to play for us, want to show the levels of commitment and are prepared to go whatever distance it takes to get the result.”
Bamba to the Rams?
Former Leeds United captain Sol Bamba has been training with Derby.
The 31-year-old Ivorian is a free agent after leaving Leeds for personal reasons before the closure of the transfer window in August.
Bamba played for Pearson when the pair were at Leicester City, but the Rams boss says there has yet to be any talks over a possible contract.
“I don’t think it’s something to discuss openly when it’s not been discussed internally,” he said.
“I’ve worked with him before and he’s been happy to come in and train with us, so we’ll leave it at that.”