James Holmes received thousands from grad-school grants ahead of deadly Aurora shooting

(CBS/AP) The graduate student accused of being the lone gunman in the deadly massacre at a Denver-area movie theater Friday lived on thousands of dollars in federal and school money.

James Holmes was the recipient of a $21,600 grant from the National Institutes of Health, a research agency of the Department of Health and Human Services, according to agency records. The grant lasted from July 2011 through June. Holmes also received a $5,000 stipend from the University of Colorado-Denver, where he was a first-year Ph.D. student in its neuroscience program.

Previously, CBS News reported that Holmes spent $15,000 to stockpile a massive arsenal, which included bullets and ballistic gear bought online and four guns from brick-and-mortar stores that were found at the shooting that left 12 people dead and 58 others injured. However, it's not clear whether Holmes used his grant money to fund his weapons purchases.

"This was his only known income, so this brings up -- you know, in the most unintended consequence possible -- what you have here is the specter of a federally funded shooting because this appears to be the money he had access to during the time he was planning this," senior correspondent John Miller, a former FBI assistant director, said.

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The grants were dispersed in monthly stipends of $2,216.67. The National Institutes of Health provided the information in response to a request from CBS News under the Freedom of Information Act.

"That's the national standard for supplying living stipends to Ph.D. students, so they can devote 100 percent of their effort to their research," Barry Shur, dean of Colorado's graduate school, told reporters Monday.

Holmes, 24, is being held in isolation as authorities continue to investigate the shooting. Police say he also booby-trapped his apartment with the intent to kill police officers. He is expected to be charged Monday.

Holmes spent a year in the small doctoral program, surrounded by scientists and roughly three dozen classmates delving into the inner workings of the brain.

The university isn't saying if they had any warning signs.

Experts say, however, the intimacy of the program and its focus on the brain may not have been enough for staff and students to detect that Holmes was on a course leading to what he's accused of doing.

Supported by the prestigious federal grant, Holmes was studying such topics as how the brain works or malfunctions or helping develop drugs to treat epilepsy and other disorders.

But it is not behavioral science or psychology, experts say.

David Eagleman, who runs the Initiative on Neuroscience and the Law at Baylor University, told The Associated Press some neuroscientists are experts in mental illnesses and aberrant behavior, but others spend most of their time studying molecular chemistry.

"It's really only a fraction of professors" who could identify a simmering mental disorder, Eagleman said. "Many people in neuroscience are not specialized in the issue of picking up mental illness ... There are plenty of people who just study mice and cats and stuff like that."

The school refuses to say what specifically Holmes studied. But an online syllabus listed him as making a presentation in May during a class called "Biological Basis of Psychiatric and Neurological Disorders."