An autopsy determined Thursday that Tony-winning actress Natasha Richardson died of a brain injury during a beginner's ski lesson at a Quebec resort.

According to Ellen Borakove, a spokeswoman for the New York City medical examiner's office, the cause of death was epidural hematoma - bleeding between the skull and the brain's covering. Richardson's death was ruled an accident.

Immediately after the fall, Richardson said she was fine and reportedly turned away emergency responders, although ski patrollers recommended she'd see a doctor. About an hour later, she complained that she didn't feel well. The actress was hospitalized Tuesday in Montreal and later flown to Lenox Hill Hospital in New York, where she died Wednesday at the age of 45.

Richardson and husband, actor Liam Neeson, have ties to the Hudson Valley. The couple owns a home in Dutchess County and sat on the advisory committee of the Jacob Burns Film Center in Pleasantville.

"[Her death] really got to me," says Alan Shapiro, of Briarcliff. "It just shouldn't happen."

Richardson comes from a British acting dynasty - the daughter of Oscar-winning actress Vanessa Redgrave and producer Tony Richardson. She divided her time between stage and screen, winning a Tony on Broadway for her performance as Sally Bowles in a 1998 revival of "Cabaret."

She also appeared in New York in a production of Patrick Marber's "Closer," as well as a 2005 revival of Tennessee Williams' "A Streetcar Named Desire," in which she played Blanche opposite John C. Reilly's Stanley Kowalski.

Her most notable film roles came earlier in her career. Richardson played the title character in Paul Schrader's "Patty Hearst," a 1988 biopic about the kidnapped heiress for which the actress became so immersed that even between scenes she wore a blindfold in order to better identify with her real-life counterpart.

Richardson's death has sparked a debate over the use of safety helmets on ski slopes. According to medical experts, had Richardson been wearing a helmet, the outcome could have been different.

AP wire services were used in this report.