Junior Seau's death has been ruled a suicide by the San Diego County medical examiner's office.
An autopsy Thursday confirmed that the former NFL linebacker died of a gunshot wound to the chest, the medical examiner's office said.
Seau's family has decided to allow researchers to study his brain for evidence of damage stemming from concussions, San Diego Chargers chaplain Shawn Mitchell told The Los Angeles Times on Thursday.
"The family was considering this almost from the beginning, but they didn't want to make any emotional decisions," Mitchell said. "And when they came to a joint decision that absolutely this was the best thing, it was a natural occurrence for the Seau family to go forward."
Seau died Wednesday in his home in suburban Oceanside.
Police Chief Frank McCoy said Seau's girlfriend reported finding him unconscious with a gunshot wound to the chest and lifesaving efforts were unsuccessful. A gun was found near him, McCoy said. Police said no suicide note was found and they didn't immediately know who the gun was registered to.
Seau's ex-wife, Gina, told The Associated Press on Wednesday that Seau sustained concussions during his 20-year career. She said she didn't know if the effects of concussions contributed to Seau's death. Seau starred with his hometown San Diego Chargers for 13 years before playing with the Miami Dolphins and New England Patriots.
The Associated Press contributed to this report.