The defense attorneys, in their request to an Arapahoe County district judge, are seeking a court order requiring prosecutors to turn over the contents of a package that Holmes sent to his psychiatrist Lynne Fenton - a professor at the University of Colorado-Denver s medical school and the director of student mental health services at the Anschutz Medical Campus.
The filing, however, didn't disclose how long Holmes had been seeing Fenton, or for what condition, if any, he was being treated.
On July 16, Holmes mailed Fenton a notebook filled with stick-figure drawings that showed a massacre. Fenton didn't receive the package until after Holmes was arrested.
The report comes as Holmes has told his Colorado jailers he doesn't know why he is locked behind bars.
The jailers, who come in contact with the doctoral dropout of neuroscience, believe he is faking amnesia.
While in police custody, Holmes puzzled detectives who supposedly saw him using evidence bags as puppets.
A jail worker has also said that Holmes wanted to know how the movie ended.
Experts believe he could be experiencing a genuine psychotic episode or foreshadow an insanity defense from his lawyers.
A former University of Colorado graduate student accused of a recent shooting rampage at a Denver-area movie theater had been under the care of a psychiatrist, reports say.
The disclosure came in court documents released on Friday by lawyers of 24-year-old Holmes, who is in custody on charges of entering a packed cinema showing the latest Batman movie “The Dark Knight Rises” in the Denver suburb of Aurora on July 20, killing 12 people and wounding 58 others, Reuters reported.