The British rider was airlifted to hospital after an accident at the same part of the Japanese track where Dajiro Kato was killed in 2003, prompting MotoGP to stop using the circuit.
Rea fell into a coma, police revealed upon his hospitalisation, but there are now signs of optimism.
His family posted on Rea’s social media on Thursday: “We would like to send a quick update in regards to Gino’s current condition.
“The results of the CT-Scan showed signs of recovery with [reduced] swelling.
“He is in a stable condition and recovering from the usual side effects from such a trauma.
“We are looking forward to a Speedy G recovery from him as we all know he is capable of it.”
The motorcycle racing community has united in support of Rea after his crash.
MotoGP riders including Marc Marquez, Aleix Espargaro and Joan Mir have thrown their support behind him.
Rea has raced in Moto2, World Supersport and BSB as well as EWC.