A campaign spokesperson for presidential candidate Michele Bachmann says a report documenting the severity of the Minnesota congresswoman's migraines is overblown. But, there has been at least one admitted instance of Bachmann being sidelined for days due to a severe migraine and other instances of her falling ill on the House floor.

In an article posted by The Daily Caller Monday night, un-named sources described Bachmann's migraines as regular and debilitating, often interrupting her work schedule.

Alice Stewart, national press secretary for Bachmann's White House bid, joined the campaign in mid-June, and Stewart says she has seen no evidence of migraines disrupting the aggressive schedule.

"We've been going six, seven events a day," says Stewart, "(Bachmann) has not missed a single event due to her headaches."

Stewart confirms Bachmann does get headaches occasionally, but "they are manageable with medication."

Tuesday, Bachmann addressed this health issue, reading a prepared state at a campaign event in Aiken, South Carolina.

"I have maintained a full scheduled between my duties as a congresswoman and as a presidential candidate traveling across the nation to meet with voters in the key, all important states, early states of South Carolina, Iowa and New Hampshire," Bachmann said. "I was prescribed medication that I take on occasion whenever symptoms arise, and they keep my migraines under control, but I'd like to be abundantly clear. My ability to function effectively will not affect my ability to serve as Commander in Chief."

So far, most political insiders tend to agree and say this issue probably won't hurt Bachmann's chances much.

This may be Bachmann's first public acknowledgement of her recurring migraines. Last July, the congresswoman was briefly hospitalized after a migraine developed while she was in the U.S. Capitol. And in a portion of an un-aired interview conducted a few days later with Fox News, Bachmann described the on-set of the migraine."I had a sudden illness that came on. And the attending physician in the Capitol said that I needed to just go in. I had a terrible migraine. So I went in, and they tried to deal with it. And it was probably another four days that it took me to kinda get over that. And now I'm fine."

Bachmann would later say in the August 2010 interview that she'd never had a migraine have that kind of effect on her.

The Daily Caller reports there was another debilitating migraine for Bachmann last October in the Connecticut home during a Bachmann fundraiser.

Dr. Richard Kraig, a neurologist at the University of Chicago Medical, says migraines should be thought of as ripples of brain activity like the waves caused by a pebble tossed into a still pond.

"The ripple or wave of intense activity in brain tissue is followed a by lack of brain activity," says Kraig.

That prompts the brain to release exhaust or chemicals associated with sensing pain to the outermost portion of the brain where sensitivity is keenest. The result is often a headache, Kraig says, which is at first sharp and powerful then followed by a dull pain. A typical migraine can last anywhere from four to 72 hours.

Medical research is inconclusive on the specific cause of migraines, although those who suffer from them have discovered so-called triggers through keeping details in a migraine journal. The array of triggers runs from overly-bright lights and caffeine intake to stress and extreme heat.

Kraig also notes that 75 percent of migraine sufferers are women, and most people experiencing migraines have genetic factors making them more susceptible. Treatment can be as simple as over-the-counter, anti-inflammatory drugs to a range of prescription medications.  

Steve Brown is an author, radio broadcaster and seminary professor at Reformed Theological Seminary in Orlando, Florida.