Jon Hamilton

When you sleep in unfamiliar surroundings, only half your brain is getting a good night's rest.

"The left side seems to be more awake than the right side," says Yuka Sasaki, an associate professor of cognitive, linguistic and psychological sciences at Brown University.

Ian Burkhart, now 24, was paralyzed in 2010 after diving into a wave in shallow water. The accident left him with some arm movement but no use of his hands.

First, Alzheimer's takes a person's memory. Then it takes their family's money.

That's the central finding of a report published Wednesday by the Alzheimer's Association on the financial burden friends and families bear when they care for someone with dementia.

Given recent advances in teleportation, it's reassuring to know that the human brain's navigation system appears to work just fine when we're beamed from place to place.

There's growing evidence that a lack of sleep can leave the brain vulnerable to Alzheimer's disease.

"Changes in sleep habits may actually be setting the stage" for dementia, says Jeffrey Iliff, a brain scientist at Oregon Health & Science University in Portland.

The brain appears to clear out toxins linked to Alzheimer's during sleep, Iliff explains. And, at least among research animals that don't get enough solid shut-eye, those toxins can build up and damage the brain.

Taking antidepressants during the second or third trimester of pregnancy may increase the risk of having a child with autism spectrum disorder, according to a study of Canadian mothers and children published Monday in JAMA Pediatrics.

But scientists not involved in the research say the results are hard to interpret and don't settle the long-running debate about whether expectant mothers with depression should take antidepressants.

A look at the brain's wiring can often reveal whether a person has trouble staying focused, and even whether he or she has attention deficit hyperactivity disorder, known as ADHD.

A team led by researchers at Yale University reports that they were able to identify many children and adolescents with ADHD by studying data on the strength of certain connections in their brains.

Patterns of gene expression in human and mouse brains suggest that cells known as glial cells may have helped us evolve brains that can acquire language and solve complex problems.

Scientists have been dissecting human brains for centuries. But nobody can explain precisely what allows people to use language, solve problems or tell jokes, says Ed Lein, an investigator at the Allen Institute for Brain Science in Seattle.

A brain system that helps us find our way to the supermarket may also help us navigate a lifetime of memories.

At least that's the implication of a study of rats published in the journal Neuron.

It found that special brain cells that track an animal's location also can track time and distance. This could explain how rat and human brains are able to organize memories according to where and when an event occurred.

For a few days this week, a convention center in Chicago became the global epicenter of brain science.

Nearly 30,000 scientists swarmed through the vast hallways of the McCormick Place convention center as part of the annual Society for Neuroscience meeting. Among them were Nobel Prize winners, the director of the National Institutes of Health, and scores of researchers regarded as the international rock stars of neuroscience.

Babies born prematurely are much more likely than other children to develop autism, ADHD and emotional disorders. Now researchers think they may have an idea about how that could happen.

There's evidence that preemies are born with weak connections in some critical brain networks, including those involved in focus, social interactions, and emotional processing, researchers reported at the Society for Neuroscience meeting in Chicago.

A drug that's already approved for treating leukemia appears to dramatically reduce symptoms in people who have Parkinson's disease with dementia, or a related condition called Lewy body dementia.

A pilot study of 12 patients given small doses of nilotinib found that movement and mental function improved in all of the 11 people who completed the six-month trial, researchers reported Saturday at the Society for Neuroscience meeting in Chicago.

The benefits of talk therapy for depression have been overstated in the scientific literature, according to a study in the journal PLOS ONE.

The finding comes several years after a similar study reached the same conclusion about antidepressant drugs.

A mind-altering drug called ketamine is changing the way some doctors treat depression.

Encouraged by research showing that ketamine can relieve even the worst depression in a matter of hours, these doctors are giving the drug to some of their toughest patients. And they're doing this even though ketamine lacks approval from the Food and Drug Administration for treating depression.

When it comes to sleep, fruit flies are a lot like people. They sleep at night, caffeine keeps them awake, and they even get insomnia.

Those similarities, along with scientists' detailed knowledge of the genes and brain structure of Drosophila melanogaster, have made the fruit fly extremely valuable to sleep researchers.

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