Racing driver Felipe Massa said he saw Michael Schumacher's mouth move as he spoke to him in hospital.
Massa said he feels "very positive" about the racing champion's condition after visiting him in the Grenoble hospital where the former Ferrari star has been recovering after suffering serious head injuries in a skiing accident in December.
"He was sleeping, and I was very positive because he was normal. He looks normal, and he also gave some reactions with the mouth and everything. I have no experience to say anything. I'm not a doctor. But when I saw him, for me, it looked very positive."
Speaking to reporters at the Sakhir circuit, Massa, who has been in Bahrain for Winter Testing said: "I always try to be optimistic. I saw him, I talked to him, I told him everything I did in Jerez (at the first test), about my car, the new team (Williams), everything. I told him to wake up many times... I'm positive. We need to believe.
"It's always very difficult to say because I have zero experience about what the doctors say.
"But I saw him and was very happy to be together with him for a very long time, talking to him, trying to give the best energy and just help him.
"He's a very strong man, a very great man and I really hope he can wake up, and I really hope he can enjoy his life again."
Schumacher was placed in an induced coma eight weeks ago following a skiing accident on the French resort of Meribel.
The Formula One champion was skiing off piste when he fell and struck his head on a rock which such force that his helmet split into two.
He required two operations to remove blood clots from his brain after which he was put in an induced coma.
The racing champion's manager Sabine Kehm explained that the seven times racing champion was now in the "waking-up process."