Peters, who has worked closely with Liverpool and has a long-standing relationship with England captain Steven Gerrard, will be involved with Hodgson's squad and the manager is pleased to have him on board.
"It is not just any psychologist," he said.
"It is Dr Steve Peters, who is a very famous man in that area.
"He has a great CV of working in different sports and has been doing some work with Liverpool and Brendan Rodgers so Steve knows him well.
"It is something we have spoken about for some time but we wanted to get the right man - luckily Brendan let me talk to Steve and he has accepted our invitations so we are happy with that."
Peters has also worked successfully with the Great Britain cycling team and five-time world snooker champion Ronnie O'Sullivan.
"It is unfortunate of course," Hodgson said of Walker's hip injury.
"He hasn't played for the last two or three games and we were hoping he would recover but he needs at least another week before he will be fit to play.
"He was with us last night, we had a 'Brazil' meeting to put our plans forward.
"There aren't that many defenders so there is a good chance, if you insist I tell you Glen Johnson will get his 50th cap at right-back then I can say yes."
Gerrard is joined in the England squad by Liverpool team-mates Johnson, Raheem Sterling, Daniel Sturridge and Jordan Henderson and the skipper wants to see their club form relate into a good international showing if they are selected.
"I think we have got five in the squad and everyone is in good form and feeling confident," he said.
"If everyone is selected hopefully they can bring their performances tomorrow night. We are happy with where we are in the table.
"You have got to give credit to Brendan Rogers - if you are good enough he plays you. He is not scared and he has been paid back by them with top-class performances."
Both Hodgson and Gerrard were involved in Tuesday's team meeting geared to the summer's World Cup, with preparations for Denmark kicking in on Wednesday.
Although he would not be drawn into the intricacies of the meeting, Hodgson said he was hoping to instill a family feel amongst his squad.
"It [the meeting] was heavily focused on Brazil and it was the only time to do that," he said.
"Part of the meeting was the obvious, about logistically what our plans are and where we are staying and for how long.
"What I said about the actual tournament was nothing spectacular but I don't think it is right to go out and broadcast those things.
"I like to think that sometimes in the world of football you can do things in the comfort of your own home, a dressing room or meeting room.
"You can speak to players and tell them quite frankly and honestly - like talking to family members - what is on your mind without finding out the next day a newspaper or TV company has broadcast your every word."
- Sports & Recreation
- Brendan Rodgers
- Glen Johnson