neuroscience

Itch can be a useful warning sign, or a maddening symptom with no cure. But the origins of itch have long been a mystery. Scientists think they've come closer to understanding the origins of itch in a molecule that makes mice scratch like mad.

Researchers say they can measure how much pain someone is experiencing and even watch as prescription painkillers relieve it. The scanning technique could help doctors treat pain better, but the work is also fraught with questions about how the technology could interfere with the relationship between doctors and patients.

Philosophers, poets and psychologists have long shared a fascination with dreams. Now Japanese scientists have scanned the brains of dreaming volunteers to create a lexicon of imagery that can be used to detect and decode dreams while a person sleeps.

For more than a century, neurons have been the superstars of the brain. Now researchers say that when they placed human versions of another type of brain cell into mice brains, the mice grew up to be faster learners. This supports the hypothesis that these glial cells — and not just better-known neurons — play an important role in learning.

Scientists are beginning to understand how people focus on a single voice in a crowded, noisy room. This ability, known as the "cocktail party effect," appears to rely on areas of the brain that have completely filtered out unwanted sounds.