De Villota, 33, was discovered dead in her hotel room in Spain Friday, and a forensic doctor concluded she had died "as a consequence of neurological injuries she suffered," the De Villota family said in a written statement.
De Villota was a reserve Formula One driver and was involved in a nasty crash in 2012 during a test session. The incident cost her right eye and resulted in other head injuries.
Britain's Health and Safety Executive was looking into the possible connection between De Villota's death and the 2012 crash, the BBC said.
The Formula One drivers' association said competitors in Sunday's Japanese Grand Prix would hold a moment of silence for their former colleague prior to the race.