Noriko Tanaka (田中紀子 in Japanese) , born Noriko Wakahisa, was the mother of Leiko Tanaka and Noriko Null's grandmother.
A respected professor of archeology and comparative mythology, she tried to use the Core to gain information about gods and aliens but her mind was heavily damaged. 
Bob Null named his daughter after Noriko because she was of the few topics that still made Leiko happy.
SPOILER WARNING: Plot details after Beyond The Impossible #189
Officially dead for decades, she was actually kept isolated by her daughter Leiko and later used as a vessel for the Core. Noriko briefly regained control and was able to meet her granddaughter for the first time, before being killed by Leiko.