An embalmed head found in the woods of western Pennsylvania belonged to a woman who likely died of heart problems, investigators have revealed.
But authorities still don't know who she was or why her head was severed from her body. after it was embalmed.
The most recent revelation, that the woman was taking the prescription drugs lidocaine and atropine at some point before her death, was uncovered through tests run on the woman's hair at the FBI Forensic Lab in Quantico, Virginia, the Associated Press reports.
The head was discovered Dec. 12, 2014 by a boy who was walking through the woods in Economy Borough.
In an effort to help ID the woman, authorities created sketches of her face and even made a 3-D model of her head.
"Her identity is a priority of this investigation," Economy police Chief Michael O'Brien said.
Also to help in the investigation, police hired the help of a firm that tests isotopes in her body. These elements form in the body from what humans eat and drink and they differ regionally.
The tests indicated the woman moved around between several places in the months before her death.
The tests showed the woman likely lived somewhere in the Allegheny Mountain region that stretches from eastern New York to northern West Virginia.
A burial service was held for the head on the anniversary of its discovery this month.
Authorities also held a press conference this week regarding the burial in order to try to jump-start new leads in the investigation a year on.