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A week has passed since July 20th's horrific movie theater shooting in Aurora, Colorado, and in the days following, we've come to learn a great deal about The Dark Knight massacre's prime suspect, James Holmes.

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Court documents filed by the 24-year-old suspected gunman's lawyers today revealed Holmes was a patient of a University of Colorado psychiatrist prior to last week's mass shooting.

Additionally, unconfirmed reports claim that Holmes, a neuroscience student at the university, had mailed a notebook filled with gruesome sketches and details of his plans for the attack to Anschutz Medical Campus psychiatrist Dr. Lynne Fenton before the shooting. The notebook was in a package sent to a professor at the University of Colorado, where Holmes was a Ph.D. candidate until dropping out of school just prior to the killings.

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Holmes, who has since been kept in solitary confinement, is reportedly refusing to cooperate, claiming amnesia of the events, reports The Daily Mail. A jail staffer at the Arapahoe County Detention Center tells the newspaper that the suspect "claims he doesn't know why he's in jail," asking, 'Why am I here?'"

Defense lawyers are expected to pursue an insanity defense at trial.

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Holmes will be formally charged next Monday, July 30. He likely faces charges of first-degree murder, an offense that carries a possible death penalty if he is convicted.