Feature: First week of Colorado theater shooter trial ends with graphic images

The first pictures of bloody, dead people killed by admitted mass murderer James Holmes evoked widespread emotional responses in court Thursday, even from his parents.

Relatives of 23-year-old Micayla Medek ran from the courtroom when her dead body was seen on the courtroom's monitor.

That was when Holmes' father Robert, an anti-fraud scientist and Stanford and Berkeley graduate, started chewing on the side of his right index finger while his wife Arlene slowly wiped her eyes, blew her nose, and adjusted her hair.

It was Holmes' parents' first public, emotional response since their son admitted killing 12 and injuring 58 by ripping them apart with gunfire on July 20, 2012.

Holmes' parents sat in the front row of the courtroom, still as statues behind their son, since the trial began Monday.

Holmes has pleaded "not guilty by reason of insanity" to the mass shooting, considered one of the worst in the U.S. history.

If Holmes is found to be sane at the time of the shooting, he faces execution.

Thursday's six witnesses were all law police officers. All of them were asked by prosecutors to identify the man arrested outside the rear of the theater minutes after the shooting.

All of them looked or pointed at Holmes, sitting only a few feet away, when asked to identify the man they arrested.

The first three responders to arrive endured the most "unforgettable" memories imaginable. Five of the six who testified broke down in tears remembering the scene.

"It was an absolute nightmare, it looked like a war zone," said Aurora Police Officer Justin Grizzle, who provided the most powerful testimony of the day.

One of the first policemen on the scene, Grizzle entered the dark, smoke-filled theater with white strobe lights flashing, smelling death and sweat rising from the deceased, he described.

"I saw lots of trauma," he said, "There were people yelling, screaming, crawling...it was horrific."

Grizzle's testimony shocked the court, when he broke down and uttered profanities.

Defendant Holmes, heavily mediated on anti-psychotic drugs, sat emotionless during the proceedings.

Holmes' mother published a book three months ago about her son's severe schizophrenia, saying he should not be called a monster, but a "sick" man.

But all week in court, tears have flowed for the people whose sons were killed, with Holmes "insanity" defense weakening by the day against the unfathomable tragedy he created.

Holmes graduated from the University of California-Riverside with a 3.949 GPA, and was one of only six students admitted into the University of Colorado's prestigious Neuroscience Ph.D. program.

But despite his consistent academic brilliance and self-confidence, Holmes failed academically for the first time in his life due to social adaptation issues, as indicated in numerous published emails.

That was when he spiraled downward rapidly, buying four guns, more than 10,000 rounds of ammunition, tactical gear, bomb-making materials and more in just two months.

Despite a "normal", happy childhood, Holmes was clearly distant from his family, by not disclosing his "desire to kill people" since he was 13, and his deep unhappiness prior to the shooting, according to therapists who interviewed him.

Last month his parents propelled themselves into the media spotlight by publishing a book saying their son was "not a monster" but suffered from a severe "mental" disease; and that Arlene prayed to the victims every day.

In the past few weeks, families of the deceased have called the book "an insult". Endi