Former Formula 1 driver Alex Zanardi has shown "signs of interaction" as the Paralympic champion remains in semi-intensive care after a road accident, doctors said on Thursday.
In a statement, the San Raffaele hospital in Milan said he "responds with transient and initial signs of interaction with the environment" to visual and acoustic stimuli.
Despite Zanardi's significant progress, doctors say it is still too early to make a prognosis because of the "complex overall clinical situation".
The statement added that the 53-year-old Italian had recently undergone craniofacial reconstruction after suffering serious head injuries when he lost control of his handbike during a road race in Tuscany and crashed into an oncoming truck on 19 June.
"A first intervention has already been successfully performed a few days ago, and a second is already planned for the next few weeks," it said.
Zanardi had both his legs amputated after a motor racing accident in 2001 at the Lausitzring track in Germany, and has since become one of the best-known figures in Paralympic sports.
He raced for Jordan, Minardi and Lotus in F1 in the early 1990s before switching to the CART championship in the United States where he was series champion in 1997 and 1998.
He returned to F1 with Williams in 1999 before heading back to CART.
Zanardi won two gold medals at the 2012 London Paralympic Games and four years later won two more in Rio de Janeiro.