Bluetooth is commonly used for yammering on the phone or driving a computer cursor.

Jennifer LaForest used it to regulate the secret electrical impulses traveling up and down her spine.

LaForest, 26, of Auburn Hills, Mich., last month became the first person to use Fridley-based Medtronic Inc.'s new Bluetooth-enabled Verify Evaluation System to temporarily control the electrical signals that tell her body when it has to go to the bathroom and when it doesn't.

She said the two-piece system is totally unlike the obtrusive box her mother once wore — the kind that experts say can exacerbate the shame of a condition like incontinence.

"The older box, the one my mom had, she had to wear a huge box on a belt and she controlled it with a dial," LaForest said in a phone call. "With the Verify system, it's on Bluetooth. ... It's very small, and you just wear it under your clothes."

External neurostimulation devices are intended to be worn for about two weeks — just enough time to verify that the patient will benefit from having Medtronic's InterStim device permanently implanted under the skin, which LaForest eventually did. Such devices, temporary or permanent, are typically recommended only after behavior modifications and drug therapies fail to bring the symptoms under control.

LaForest spent 11 years dealing with two problems: sometimes she had an overactive bladder, and other times her body would send false signals to urinate. Researchers say that many cases of incontinence are caused by malfunctions in the electrical impulses that travel between the brain and the complex nest of nerves that control muscles and sensations in the bowel and bladder.

Scientists have found applying a small electric current to the sacral nerves that weave through natural holes in the pelvis can normalize how signals travel between the brain and the bowels and alleviate the symptoms of incontinence in the process.

But the electric leads must be precisely positioned, and the current has to be calibrated to the patient's needs, which is part of the reason temporary rigs are used before an InterStim unit is surgically implanted, in the upper part of the buttock.

Although sacral neurostimulation devices for incontinence have been around since 1997, engineers eventually came to realize that the design of their temporary evaluation system might contribute to some of the tangled emotional barriers involved with treatment using a device.

"Oftentimes people living with bladder or bowel incontinence will feel shame related to the condition. Some people will limit their social activities" or stop leaving the house altogether, said Linnea Burman, Medtronic's vice president and general manager of gastroenterology and urology therapies. "One of the original requirements of the (redesigned) device was to fit discretely under the person's clothing."

The Verify consists of a small hub worn under the clothing that delivers current, controlled by a Bluetooth-enabled remote controller that looks like a smartphone and delivers more precise information than the old dials.

"Those of us who do these procedures were anxiously awaiting this," said Dr. Ken Peters, LaForest's doctor and chief of urology at Beaumont Health System in Royal Oak, Mich.

Medtronic, which makes the only sacral neurostimulation devices on the market, sees big potential for the Verify: About 37 million people are believed to have overactive bladders, and another 18 million have bowel incontinence.

The temporary Verify and permanent InterStim therapies together cost between $20,000 and $30,000, which is typically covered by insurance. The new technology in the Verify adds a couple hundred dollars to the cost of the therapy. Although the old devices were reused by multiple patients, the Verify is designed for a single use.

Peters, who described himself as a "a big fan of InterStim," said he hopes buzz for the new system will generate more awareness among incontinence patients who haven't gotten results from drug therapies.

"It's not a subtle improvement. When people get better, it's a big deal," Peters said. "It's usually like, 'Wow, why didn't I do this year ago?' "

Joe Carlson • 612-673-4779 • Twitter: @_JoeCarlson