Quell, a new electrical-stimulation device designed to help alleviate chronic pain, gets wrapped around the wearer’s calf. Quell works through neurostimulation, delivering precisely controlled, low-level electrical stimulation to patients suffering from chronic pain due to diabetic neuropathy, sciatica, fibromyalgia and other ailments. The electrical signal travels up the central nervous system to the brain, releasing opioids that tame pain.

Pain is a leading cause of disability in the US, affecting more Americans than cancer, diabetes and heart disease combined. But in a new study, researchers say they have discovered an "off switch" for pain, paving the way for new treatments. By activating the A3 receptor in the brain with a small adenosine molecule, researchers say they could prevent or reverse chronic pain. The research team, led by Daniela Salvemini, professor of pharmacological and physiological sciences at Saint Louis University, MO, publish their findings in the journal Brain.

A new study led by Brown University reports that older learners retained the mental flexibility needed to learn a visual perception task but were not as good as younger people at filtering out irrelevant information.

The findings undermine the conventional wisdom that the brains of older people lack flexibility, or "plasticity," but highlight a different reason why learning may become more difficult as people age: They learn more than they need to. Researchers call this the "plasticity and stability dilemma." The new study suggests older people may indeed be facing it.

For many people suffering depression, antidepressant medications provide sufficient relief. But up to 50 percent of those diagnosed with major depressive disorder (MDD) will not respond to these drugs.

Some people with MDD try several antidepressants and still can’t find relief. They will be deemed to have “treatment-resistant depression.” These folks might end up trying a combination of various drugs, talk therapy, or other treatments to help them feel better.

Sometimes nothing works.

Now, a newer, less invasive option – transcranial magnetic stimulation (TMS) – is becoming more widely available, and it doesn’t have the side effects of ECT.

The unbearable headache that migraine patients suffer is due to cellular-level changes in nerve structure, says a study.

The researchers found abnormalities of the myelin sheath that serves as "insulation" around the nerve fibers.

"Essentially, the protective layer surrounding and insulating the normal nerves, called myelin, is missing or is defective on the nerves of the patients with migraine headaches," said Bahman Guyuron from Case Western Reserve University, Cleveland.