Virginia state Sen. R. Creigh Deeds was stabbed by his 24-year-old son, who struggled with bipolar disorder. The young man then killed himself. (Matt McClain/The Washington Post)

This post has been updated. 

The federal government's top mental health researcher told lawmakers Thursday that the country needs to do much more to apply research to improve treatments, as a Senate committee heard testimony to address comprehensive mental health legislation.

Speaking on his second-to-last day in his job as director of the National Institute of Mental Health, Thomas Insel said his 13-year tenure had convinced him of two “abiding truths.”

“One is that we can do much, much better than what we’re currently doing,” he said. In the field of mental illness, unlike any other disease, “there is this unconscionable gap between what we know and what we do.”

[Why it's so hard to find a mental health professional ]

At the same time, he said, disorders of the brain are complicated and understanding them at a deeper level requires investment in more science “if we’re going to come up with treatments that are going to be more effective.”

Mental Health America, a patient advocacy group, evaluated the prevalence of mental health issues and access to mental health care in the U.S.

[Why NIH's mental health chief is leaving for Google: technology may hold key to better diagnosis ]

But the hearing before the Senate Health, Education, Labor and Pensions (HELP) Committee -- the first time the chamber has taken up mental health reform in nearly three years -- won't be the day's only discussion of mental health on Capitol Hill.

The American Psychiatric Association is hosting an afternoon briefing in the House on decriminalizing people with mental illness. According to the most recent federal statistics, about 20 percent of prison inmates have a serious mental illness and 30 percent to 60 percent have substance abuse problems.

Insel told lawmakers that the criminal justice system has become the “de facto mental health system in this country." He added: “Is this the country we want to be? Is this the way we want to treat people with a brain disorder?”

Months of deadly mass shootings have prompted renewed momentum in Congress for mental health reform, advocates and lawmakers say. On Tuesday, more than 30 mental health and medical organizations sent a letter to HELP Chairman Lamar Alexander (R-Tenn.) and ranking minority-party member Patty Murray (D-Wash.) calling for a greater effort "to provide more effective prevention measures, more timely access, and improve the continuity of care within our mental health system."

[Advocates, lawmakers see momentum for mental health legislation in Congress]

The issues could become part of the presidential campaign rhetoric — and not in the way that advocates might want. During Wednesday night's Republican debate in Colorado, Donald Trump linked mental illness and gun mayhem, saying mass shooters look for gun-free zones for their rampages.

"That's target practice for the sickos and for the mentally ill," he told moderator Carl Quintanilla.

Trump’s comments did not come up specifically during the hearing. But lawmakers and experts repeatedly cited stigma as one of the biggest hurdles for people seeking help.

“When you use terminology like that, it just reinforces the stigma and drives people away from treatment,” said Sen. Chris Murphy (D-Conn.) after the hearing. He and Sen. Bill Cassidy (R-La.), a physician, have introduced a mental health reform bill that was a focus of the hearing.

The Senate measure parallels a House bill sponsored by Rep. Tim Murphy (R-Pa.), a child psychologist.

[What is the evidence for Trump's claim about gun-free zones?]

Alexander said he expected the committee would likely hold another hearing on mental health before the end of the year and move the bill by early 2016. He also said he would work with the Senate Finance Committee on finding more resources to fund improvements and noted that turnout for the hearing -- 13 of 22 members showed up -- was one of the largest in recent memory.

In a press call afterwards, Sens. Cassidy and Murphy said they were heartened by the progress. The House is scheduled to mark up its bill next week. “The Senate process has now pulled out of the station,” Murphy said. “We hope to be able to pass comprehensive mental health reform this Congress.”

Both bills would remove barriers for Medicaid funding of mental-health treatment, fund more psychiatric beds in hospitals nationwide, establish an assistant secretary for mental health and address privacy restrictions to help families receive more information about a loved one’s condition and treatment. They also stress early intervention and diagnosis.

[Study suggests new way to treat people after first schizophrenia episode]

The demand for mental health services is growing rapidly. Nearly 1 in 5 adults — about 43 million people — had a diagnosable mental disorder within the past year. For nearly 10 million, the condition was serious enough to affect their ability to function day to day. Millions of adolescents also struggle with a debilitating mental disorder.

Yet the country is facing a serious shortage of mental health professionals, in part because of inadequate reimbursement from government and private insurance plans. More than half of U.S. counties have no mental health providers.

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