Greg Grunberg

As Heroes' Matt Parkman, Greg Grunberg can control people's minds and create fantastical realities in their heads. But the progress Grunberg's son has made in his battle to overcome epilepsy is no fantasy at all.

Grunberg's 12-year-old son, Jake, has lived with the struggles and seizures epilepsy causes, but thanks to a recent brain surgery, he is showing massive signs of improvement.

"He's doing really well," Grunberg tells TVGuide.com. "You don't try brain surgery until you've basically run out of medicine. There are so many things you try before you get to removing a piece of his brain. But they saved his life."

Grunberg says surgery became an alternative when doctors were able to pinpoint the area of the brain with the most epilepsy activity. Now, he says his son is "90 percent better" and that he is hopeful for his future. "He's living a normal life — he's not seizure-free, but he's back doing what a normal kid would do," he says. "I'd love to see Jake not have epilepsy for the majority of his life, and I think that's going to happen with what they're doing."

The actor also says his experience with his son has inevitably informed his acting, as this week Parkman met a son he never knew he even had. "That was an amazing moment for me to play," he says. "We went through a really tough year. When you go through anything tough like Parkman is going through — he doesn't care about living or dying; he just wanted revenge on this guy who basically ruined the last thing that was good in his life — and you get to the darkest place, look what happens. There's a baby that is mine. That gives you hope to live and fight."

Grunberg has also founded TalkAboutIt.org, a website dedicated to informing the public about epilepsy and providing a place for those affected by it to share their stories. "It's like the MySpace of likeminded people that are dealing with this," he says.

With the help of co-stars and friends like Milo Ventimiglia, Zachary Quinto, Jennifer Garner and Jack Black, Grunberg says he hopes to encourage people to face the disease rather than be afraid of it. "It gets the conversation going about epilepsy without it being scary. It's a huge deal, and for there to be a stigma attached to it for so long, and for people to be afraid to talk about it, it's a shame. We talk about AIDS, and we talk about cancer, and we're willing to give money to research [for those diseases]. That's what I'm hoping for epilepsy."

Grunberg spends much of his time raising money for multiple charities as a part of Band from TV. Their next gig is Heroes for Autism, an event where artwork and photos taken from the set by Heroes' cast and crew will be auctioned off for Autism Speaks. Grunberg also revealed to TVGuide.com exclusively that the band will be joined by a very special guest on stage.

"Rainn Wilson is going to be hosting, and he's going to play a song with our band," Grunberg says. "So you've got Hugh Laurie, James Denton, me, Bob Guiney, Jesse Spencer, Adrian Pasdar and now Rainn Wilson all on stage playing music for a great cause. It's selfish, because I'm having a great time, and get to pretend to be a rock star, but all the proceeds go to charity."

Between acting and all his side projects, Grunberg still remains dedicated to his fans via his website and Twitter account. (You can follow TVGuide.com on Twitter too!) Despite causing a flurry of rumors about a possible Heroes cancellation, Grunberg says he isn't "going to hold back."

"It has connected me with the fans," he said. "After last night's episode, I got so many Twitters. It's like hearing from your mom. These people are following me, so they obviously like what I do, but it's so nice to get that support."