Colin Boyd Conn had just spent an exciting summer studying at the University of Rome when he returned to his Mandeville home in 2010, complaining that he felt terrible. The LSU student was vague about his symptoms, and his mother, a doctor, at first thought he had jet lag.

But it quickly became clear that Ann Conn’s then-20-year-old son, whom she describes as athletic and outgoing with a streak of mischief, was suffering from a far more profound malady: mental illness.

Colin had severe bipolar disorder with rapid cycling, meaning he could vacillate between highs and lows many times in a day, and according to his mother, “nothing stopped it.”

That illness, which he struggled with for 3 ½ years, eventually ended his life. Colin committed suicide in May.

The note he left in his Baton Rouge apartment said that no one was to blame. “I can’t take the voices anymore,” it said.

On Friday, Conn will accept her son’s posthumous degree from LSU, a recognition for her son that she views with deep gratitude.

Even in the midst of his illness, Colin persevered, studying chemistry and physics at LSU in hopes of working in the field of brain research. He wanted to use nanotechnology to help get medicines through the blood-brain barrier, she said.

In the last year of his life, he also spoke out candidly about his disease, becoming an advocate for the mentally ill, his mother said.

Now, Conn is speaking out herself in an effort to destigmatize mental illness and encourage those who need help to pursue it. She also wants people who have mental illness in their families to consider donating their brains upon death to the Stanley Medical Research Institute in Maryland, which supports research into the causes and treatment of schizophrenia and bipolar disorders. She has already made that arrangement for herself.

Conn said her family had every reason to think that Colin would have a good prognosis, that drug therapy would make his illness manageable. His family had the means and the knowledge to seek out the best possible care for him — two critical assets, because access to mental health care can be difficult, according to both Conn and Martha Benson, program director for the St. Tammany chapter of the National Alliance on Mental Illness.

Colin was treated at McLean Hospital in Boston, which is affiliated with Harvard Medical School, and at the Menninger Clinic in Houston.

“He got the best care, and he adhered to his care,” Conn said, noting that is not always the case with psychiatric patients. In fact, his family discovered his death because he had missed a doctor’s appointment — something he never did.

But Colin’s illness was of the most severe sort, his mother said. It wasn’t until he was hospitalized in December 2010 that she learned he had been hallucinating.

While most people do well on medication, she said, Colin didn’t respond to any treatment — including experimental therapy using transcranial magnetic stimulation, usually a treatment for depression.

Benson agreed that Colin’s situation is not the norm, but 12 to 15 percent of patients do not respond to therapy.

Conn, a pain management doctor whose training was in neurology, said mental illnesses of varying degrees afflict 20 percent of people, sometimes terminally. “My son died of a brain illness,” she said.

Colin was chronically suicidal after he became sick, and she knew that the risk of his taking his life was high. She, her parents and her sister checked in with him frequently, and he had good friends who stood by him through his worst times, she said. But there were times when she worried whether he would make it through the day.

She credits LSU Disability Services with helping him to stay in school and supporting him.

“Knowledge is huge. That’s why it’s important to go to a psychiatrist and seek appropriate care. You have to direct your own care, too, and it’s hard to navigate the system,” she said.

Benson said access to treatment is a challenge, even for people who have private insurance, Medicare or Medicaid.

St. Tammany Community Health Center, with locations in Slidell and Covington, is helping to meet the need in that parish, but overall, there are not enough psychiatrists, she said.

One woman with good insurance who believed her mental health issues were resurfacing in October couldn’t get an appointment with a psychiatrist until June, Benson said, and that’s far too long a wait for someone who is coming out of remission or having an episode.

“There is help out there,’’ she said. “It is not as readily accessible or available, but it’s not impossible.’’ NAMI St. Tammany, at (985) 626-6538, can provide help to people looking for resources.

For Conn, the loss of her son is still a fresh pain. The graduate of Mandeville High School, who played football there and was a preferred walk-on his first year at LSU, would have turned 25 this month. His family plans to scatter his ashes in Canyonlands National Park, the site he requested in his suicide note.

“He’s not suffering anymore, and that helps me,” Conn said.

She also marvels at how he continued with difficult course work while coping with the torment of his illness. A professor told her Colin was one of the best undergraduates he ever worked with.

Colin had bloomed academically at LSU, where he finished coursework for a degree in psychology before deciding to pursue brain research. He had been looking into graduate programs when he died.

“People living with mental illness are like superheroes,” Martha Benson said. “Their load is so much heavier than for the rest of us.”

Follow Sara Pagones on Twitter at @spagonesadvocat.