Now speaking to German television ARD, she revealed: "There are small improvements that make us happy and give us great encouragement."
She flagged the possibility Schumacher will eventually transfer to a "rehab clinic", but said a prediction of the seven time world champion's future is not possible.
"Each case is individual; every brain injury can affect someone differently," said Kehm. "No doctor could answer these questions."
She stressed, however, that the 45-year-old is not only having moments of being awake, but also being 'conscious'.
Kehm explained that the latter is, "perhaps in a very limited form, being able to interact with the environment".
She also criticised doctors "on the outside", including former F1 doctor Gary Hartstein, who have commented on the Schumacher case despite having "no knowledge" of the details of the former Ferrari and Mercedes driver's condition.
And Kehm revealed that a journalist who dressed as a priest was not the only member of the public and media that attempted to enter Schumacher's hospital room.
"There was also another person who tried to come in (disguised) as Michael's father.
"There were a lot of cases of people who have tried to go into the ICU, perhaps to take a photo or a video," she added.