“He had told his mother that he felt there were two people living inside of him,” Anna Nikaeva said. “I told her, ‘You should get that checked out.’ But she just said, ‘No, he’s fine.’ She couldn’t accept the tiniest criticism of him. But obviously she was thinking about it enough that she brought it up.”
Nikaeva, a Chechen immigrant like the Tsarnaevs, was part of a small circle of Chechen families that knew each other in the Greater Boston area. After the brothers were named as suspects in the April bombing, Nikaeva told her husband, Makhmud “Max” Mazaev, about the 2008 conversation. Mazaev, a urologist, "speculated that Tamerlan suffered a kind of mental imbalance, probably schizophrenia," according to the Globe.
Mazaev later got in touch with a psychiatrist, Dr. Alexander Niss, who saw both the Tsarnaev parents as patients from 2003 to 2005.
“I told Niss that Tamerlan had some form of schizophrenia. That, combined with smoking marijuana and head trauma from boxing had all made him ill,” Mazaev told the Globe. “But Niss thought it was more a form of paranoia. We were just talking, you know, two doctors talking.”