(THE INDIANAPOLIS STAR) -- Jeff Herrod was the heavy-hitting, pulsating heart of the Colts defense, a self-described "seek-and-destroy" linebacker.

He led the Colts in tackling for seven seasons before retiring in 1998. But now, at age 46, Herrod said he's paying a big price.

Migraines and memory loss. Sleep issues and sensitivity to light. Full-body pain. Blink-of-an-eye mood swings.

"I know I'm not going to be any better," said Herrod, who made 1,337 tackles for the Colts and played 11 NFL seasons. "It's going to get worse. That's expected."

Herrod is among more than 3,000 former NFL players suing the league, alleging it failed to warn them about concussions, diagnose them and try to prevent them. At least 136 former Indianapolis Colts, including running back Eric Dickerson, quarterback Jack Trudeau and tight end Ben Utecht -- a member of the 2006 Super Bowl champions -- are suing.

The NFL denies the allegations, and will likely seek to have numerous lawsuits, consolidated into one case, dismissed. The filing is due Aug. 30.

"We obviously believe the charges that we have not been responsible in this area are not factually correct," NFL commissioner Roger Goodell said during an owners meeting in May. "We have taken the right steps. We have been leaders in this area. We have not waited for science."

Yet it's obvious to Herrod and his fiancée, Kate Jones, that something is wrong. During a recent meal, Jones began tapping her fingers, idly, innocently, on a plate. Herrod exploded at her.

"There definitely are mood swings," she said. "Every day you have to be aware of how he's feeling."

Getting 'dinged'
Football has euphemisms for injuries, often used by coaches in a dismissive tone. One of those is a player getting "dinged."

Herrod has learned what that really means.

"Over my career, I didn't understand the shifting of the brain," he said, "and that a 'ding' was a concussion."

Herrod said he was never diagnosed with a concussion, which occurs when the brain, usually cushioned by fluid, crashes against the skull because of a hard hit to the head.

Herrod often delivered those hits. To keep going, he always had an ammonia capsule tucked in his pants.

"If I got dinged on the field, I'd (sniff) an ammonia capsule to stay on the field," Herrod said. "I was the leader of the defense. I couldn't leave the field."

Former Colts and IU defensive end Bernard Whittington echoed that aspect of the game's culture. It's about not letting down fans and teammates, he said. Sometimes it's a matter of job security.

"You stay in there whether you get dinged or hit or anything like that," Whittington said. "That's the part that people don't understand."

Former Colts linebacker Barry Krauss said that when he does public speaking, he tells a story about an incident near the end of his career. He made a tackle, "got up, and was totally disoriented. . . . I was actually going into the wrong huddle."

Inevitably, the audience laughs. But in hindsight, Krauss said, it isn't funny.

Since last year, the suicides of former NFL players Dave Duerson and Ray Easterling have highlighted a condition called "chronic traumatic encephalopathy" (CTE), a degenerative condition caused by repeated head trauma.

Duerson, from Muncie North High School and Notre Dame, shot himself in the chest and left a suicide note saying his brain should be donated to the Boston University Center for the Study of Traumatic Encephalopathy.

Easterling's widow said the medical examiner's report showed her husband's brain showed signs "consistent with the findings of (CTE)."

Former NFL players Junior Seau and O.J. Murdock, both of whom killed themselves within the past four months, will have their brains studied for CTE.

Herrod volunteers as a research subject for Boston University researchers on CTE. He has taken various cognitive tests and endured a spinal tap and scans.

"I was in a tube for two hours, with a 10-minute break, with a cage around my head,'' Herrod said. "They're trying to come up with a way to detect (CTE) while a person is living instead of after they've died. . . . Now, the only way they know is through an autopsy.''

When Herrod dies, his brain and spine will be given to the Boston University researchers.

"They're asking former players to donate and they give you a card,'' he said. "My mother has a card. She would contact the institution and they will get my brain and spine to do their research. . . . I want to help future generations better understand brain trauma and treat it. Trust me, it's no fun.''

Herrod paused.

"Do I have CTE?" he said. "I don't know. I'm just hearing things other players are faced with -- all the symptoms and what they deal with every day -- and I'm right there with them. I think I'm a candidate.''

David Josephson, a doctor who's part of Josephson-Wallack-Mushower, the largest neurology practice in the state, said he's a fan of the NFL. But he believes, on concussions, "We are just seeing the tip of the iceberg."

The NFL points to rule changes protecting defenseless players. There are fines and suspensions for players who use their helmets as a weapon. A player who suffers a concussion during a game is not allowed to return to action, that day or in the future, before passing a neurological exam.

Late last season, the league began using medical observers at every game to monitor possible concussions. On Wednesday, USA Football launched Heads Up Football to teach kids proper tackling technique, which one kid demonstrated to Goodell.

Former NFL player Troy Vincent, currently the league's vice president for player engagement, noted that the league's annual rookie symposium stresses the long-term effects of brain injuries.

Last month, the league has NFL Total Wellness and NFL Life Line, which offer free resources for players, including experts on substance abuse and suicide prevention.

"Too often we find the athlete doesn't embrace the resources," Vincent said. "We are trying to change the culture. The last thing I was thinking about at 21, when I was drafted by the Dolphins, was what my life would look like when I was 40."

Lots of surgeries
It isn't just concussions. Herrod said he can't lift a carton of milk out of the refrigerator because of arthritis. A chance meeting with a reporter produced a handshake -- and a grimace -- from Herrod. Jolts of pain went through his hand.

Herrod has lost count of the surgeries he's had because of football.

"About 13 or 14,'' he said, adding more will be necessary. "My fingers, right wrist, both shoulders, had my left hip replaced, my left knee, a plate and screws in my right toe and same thing needs to be done to my left toe.''

Herrod made $600,000 per year in his last NFL contract. He's retired. And there good days at the Tampa, Fla., home of Herrod, Jones and her 7-year old twin sons, Alex and Trey. Every chance he gets, Herrod spends time with his six children: Shauntel, a recent graduate of Atlanta Christian College; Marcus, Jeff Jr., Marcelle, Christian and Marcellus.

"My kids keep me glued together,'' he said.

Added Jones: "They definitely are the light of his life. They bring him his joy. He loves to see them grow into the fine young adults they are.''

Herrod said he likes that his kids think of him as "a warrior. . . . That eases my pain at times."

It is considerable pain, but Herrod said he would do it again -- and try to play "smarter."

"Is it the NFL's fault? Is it my fault? I don't know,'' Herrod said. "My job was to seek and destroy. I took pride in doing that. I'm not sitting here feeling sorry for myself. I had a great career. If somebody looks at me and says, 'He was a tough SOB,' I take pride in that.''

Call Mike Chappell at 317-444-6830. Follow him on Twitter: @mchappell51. Michael Pointer contributed to this story.

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