WASHINGTON — The Pentagon must use computers to screen troops before and after they go to Iraq or Afghanistan to better determine if they suffered traumatic brain damage in combat, according to a plan by a congressional brain-injury task force.

The Defense Department should also develop more brain-injury research and improve care for what experts are calling the signature wound of these wars, one that often goes undetected until returning troops have memory or behavior problems.

Congress has authorized a record $450 million for brain-injury treatment and research in the Iraq spending bill being negotiated by Congress and the White House. Legislators say the Bush administration acted slowly on this issue.

"The military was blindsided by the number of blast injury victims in Iraq and Afghanistan, and it is clear that the proper resources were never in place to care for them," says Rep. Bill Pascrell Jr., D-N.J., co-chairman and founder of the 112-member Congressional Brain Injury Task Force.

Between 125,000 and 150,000 U.S. troops may have suffered mild, moderate or severe brain injuries in Iraq and Afghanistan, Pascrell estimates. That's a hidden population of wounded that far exceeds the official casualty figures of 26,000.

Between 10 percent and 20 percent of the returning troops screened at a few individual military bases may have suffered brain injuries, Pentagon spokesman Chuck Dasey says.

The increased funding parallels a growing sense of urgency within the civilian and military scientific community about adequate means of treating this growing category of wounded.

A Pentagon mental health task force last week warned that twin challenges of brain injury and post traumatic stress disorder have "exposed gaps" in the Defense health system.

Dr. Gregory Poland, chairman of a Pentagon scientific advisory panel that criticized the Defense Department's failure to track and diagnose brain injury, says his committee will re-examine the issue in a few months. "We really need to do something about this," Poland said.

Military scientists devised a brain-injury screening process years ago, but the Pentagon has not used it on all returning troops, Defense Department spokeswoman Cynthia Smith says. Such screenings can identify symptoms such as memory loss, difficulty concentrating or irritability.

Modern body armor has enabled troops to survive roadside bomb blasts, but they still remain vulnerable to undetected brain injuries, says Dr. Barbara Sigford, the VA's director for physical medicine and rehabilitation.

Repeated deployments for troops makes it even more important for the Pentagon and VA to "to be providing the services that they require," Sigford says.

Last month, Sigford says, the VA started traumatic-brain-injury screening for every Iraq and Afghanistan veteran who arrives at one of the department's 1,400 medical facilities. The extra money approved by Congress will be welcome, she says.