A new study shows which type of brain stimulation may work for ADHD

There’s a lot of interest in new ways to treat ADHD. The first-choice treatments are still medication and behavior therapy. But more options may be on the horizon.

A new review of studies,¹ published in the journal Frontiers in Neurology, compared several types of noninvasive brain stimulation for ADHD. Brain stimulation therapies change how the brain works without surgery. These therapies use safe electricity, magnets, or ultrasound waves to activate or calm certain areas of the brain in hopes of improving symptoms. 

Researchers reviewed 37 studies that included more than 1,600 participants who tried different types of brain stimulation for ADHD. Based on their review, researchers determined what types of brain stimulation may work for ADHD and which ones don’t. 

Let’s take a closer look.

In rTMS, magnets are placed on your head over specific areas of the brain. The goal is to activate these areas to reduce symptoms. 

The review found that rTMS (repetitive transcranial magnetic stimulation) was not helpful for managing ADHD symptoms like working memory and thinking flexibility. This tracks with an earlier study² that suggests rTMS may not be helpful for ADHD. 

However, not all the research agrees. A different review of studies³ found evidence that rTMS may improve ADHD symptoms, including inattention, hyperactivity, and impulsivity.

Because different reviews have found inconsistent results for rTMS, we need additional research to better understand if it works for ADHD.

TPS uses ultrasound waves on specific areas of the brain to activate them and help reduce ADHD symptoms.

Researchers found TPS (transcranial pulse stimulation) may have benefits for symptoms like hyperactivity and impulsivity. But there wasn’t enough evidence to say it definitely helped. This is in part because the researchers only reviewed one study on TPS.

tDCS uses low-grade electricity to activate and calm neurons in the brain. Neurons are the brain’s messengers. 

Researchers found that several types of tDCS (transcranial direct current stimulation) help people with ADHD. It improved symptoms like flexible thinking and working memory.

Other research also shows that tDCS may be helpful for additional ADHD symptoms. This includes improving inattention and cognitive control.² Cognitive control is your ability to stay focused, manage distractions, and be flexible with your thinking.

In tDCS, two electrodes, which look like sponges, are placed on the outside of your head. They’re put over areas of the brain associated with the symptoms you want to improve. Then they’re connected to a device that provides about as much electricity as a 9-volt battery, said Marom Bikson, PhD, a professor of biomedical engineering at the City College of New York. (He was not involved in the study.)

When the tDCS device is turned on, one sponge has a positive current that activates neurons in the brain. The other has a negative current that calms neurons.

In the review of studies, dual-tDCS was one of the most effective protocols for ADHD. In dual-tDCS, the electrodes are placed over front areas of the brain called the left and right dorsolateral prefrontal cortex. Another form of tDCS called anodal-tDCS may also be an effective protocol.

A typical session of tDCS lasts for 20 to 30 minutes. You repeat the therapy every day for at least 10 days. The goal is to build lasting symptom relief by repeating the stimulation for many days in a row.

Brain stimulation therapies like tDCS work because “the brain itself is an electrical organ,” Bikson said. 

“Neurons communicate with one another based on electricity,” Bikson added. “So you have an electrical system that you’re now putting electricity into, and that’s why the brain responds.”

Brain stimulation with electricity may sound scary. But keep in mind that it’s not the same thing as electroconvulsive therapy (ECT). That’s what most people think of when they think of brain stimulation. ECT uses more powerful electricity. tDCS uses low-level electricity, and it’s considered very safe with few side effects when given at the correct dosage.

Common side effects of tDCS include:⁴

• Sensations of tingling and itching on the head during treatment

• Skin redness that usually goes away after 30 minutes

• Sensations of warmth

• Temporary headaches 

• Short-term dizziness

While tDCS may be promising for ADHD, there are some important things to keep in mind. First, tDCS is not approved by the FDA for any health condition in the United States. It can still be prescribed off-label, though. That means there’s research to show it works, but it’s not FDA-approved. 

Because it’s not FDA-approved, clinicians currently don’t recommend tDCS for children. While tDCS looks like it could help people of all ages, we still need more research on its safety and effectiveness in kids.

Any type of brain stimulation therapy is not a first-choice treatment for ADHD.⁵ Behavior therapy and medication are still the best options. But for adults who don’t get enough symptom relief from traditional treatments or who want a nonmedication option, brain stimulation therapy may help.

Even though this new research provides evidence that tDCS may be effective, the research does have limitations. For example, the studies they looked at used different methods to measure symptom improvements. This makes it harder to compare results. So while therapies like tDCS show promise for ADHD, we still need more research. 

Right now, the two safest ways to try tDCS are to join a clinical trial testing the technology or go to a reputable medical center that provides the treatment. Reputable medical centers include university clinics and major hospitals. 

You may see companies selling tDCS equipment. But those come with additional risk. “The quality of these devices may vary,” Bikson said. For the treatment to be effective and safe, you also need to place the electrodes in the right spot and use the right treatment protocol. This is hard to do on your own. It’s best done with professional help.

If you’re interested in learning more about tDCS and whether it may be an option for you or your child, talk to your health care provider. Together, you can discuss the benefits, risks, and alternatives.

A new review of studies looked at whether noninvasive brain stimulation could help treat ADHD. Researchers compared three main techniques: 

• Repetitive transcranial magnetic stimulation (rTMS)

• Transcranial pulse stimulation (TPS)

• Transcranial direct current stimulation (tDCS)

rTMS showed little benefit. TPS may help with hyperactivity and impulsivity, but evidence was limited.

The most promising results came from tDCS. It uses mild electrical currents to activate or calm certain parts of the brain. Experts say that tDCS appears safe when it’s done correctly. There were only mild side effects, like tingling or redness. 

But tDCS is not yet FDA-approved in the U.S. It should only be used under medical supervision or as part of a clinical trial. More studies are needed before brain stimulation can be considered a reliable ADHD treatment.

Thumbnail image credit: Jesus Rodriguez via Getty Images.