Trojans coach Lane Kiffin said over the weekend that Barkley made some "really poor decisions" in USC's 21-14 loss to the Cardinal at Stanford Stadium.
"Yeah, I made some poor decisions," Barkley said after the Trojans practiced on Tuesday. "But that's why you watch the film and learn from it."
After reviewing the film from the game, Kiffin said in a Sunday evening conference call with reporters that Barkley made "probably two of his worst decisions in our three years together."
Asked about that comment on Tuesday, Barkley said he appreciated the honesty.
"He's going to be real, you know?" Barkley said. "He is going to defend me when he has to and he's going to be real when he has to. I'm glad he's not hiding me behind a curtain or anything like that.
"I know what I did. It's not like he's making fun of me or something to the public."
Barkley said the Stanford loss took him by surprise.
"I wasn't expecting that," he said. "I didn't think that was going to happen this year."
But, he said, he deserves much of the blame for the loss.
"It's my team and my offense, so I know we are responsible for doing more than that and we're capable of more than that," Barkley said.
No. 13 USC, which dropped from No. 2 with the loss, hosts Cal on Saturday at the L.A. Memorial Coliseum.
Barkley said he had moved on to the game "24 hours" after the Stanford loss -- but he was still using it as motivation as he prepared for the Bears.
"You learn a lot through a defeat like that," he said. "I'd say you learn how to come back the next day and respond to your team and be the voice that they need.
"It's what football is all about. You enjoy the victories and you learn from your mistakes and tough games like that."
Pedro Moura covers USC for ESPNLosAngeles.com.