When stroke symptom onset is unknown, basing emergency clot-busting treatment on the time patients were last seen normal may be beneficial. Clot-busting drugs are only recommended for stroke patients within three to 4.5 hours of symptom onset.

Cognitive impairment is common in transient ischemic attack and minor ischemic stroke patients. Cognitive impairment in these patients can be detected with tests that evaluate the brain's "executive functions" -- but not with another commonly used screening designed to test for Alzheimer's dementia.

The American Stroke Association and other organizations have spent the last decade changing the care delivery system for stroke in the United States. Now the focus must include greater emphasis on prevention and recovery, according to a special report published in Stroke: Journal of the American Heart Association.

Older women who are divorced, separated, or widowed or who have never married havetwice the uninsured rate of their married peers, according to a new policy brief from the UCLA Center for Health Policy Research. The study, entitled Health and Health Care Access Among California Women Ages 50-64, examines a range of health issues among California's approximately 3 million older women, an age group that often faces new and accelerated chronic health conditions.

Integrating real-time Internet-based infectious disease surveillance with knowledge of worldwide air traffic patterns could help in confronting infectious disease threats at mass gatherings, such as the Olympics and other large scale events, suggests an article in CMAJ.

An international research team led by Columbia University Medical Center successfully used mouse embryonic stem cells to replace diseased retinal cells and restore sight in a mouse model of retinitis pigmentosa. This strategy could potentially become a new treatment for retinitis pigmentosa, a leading cause of blindness that affects approximately one in 3,000 to 4,000 people, or 1.5 million people worldwide. The study appears online ahead of print in the journal Transplantation.

With a changing climate there's a good chance that forest fires in the Pacific Northwest will become larger and more frequent -- and according to one expert speaking today at a professional conference, that's just fine. It will ultimately be good for forest health.

Higher intelligence is associated with liberal political ideology, atheism, and men's (but not women's) preference for sexual exclusivity. More intelligent people are statistically more likely to exhibit social values and religious and political preferences that are novel to human evolution. Specifically, liberalism and atheism, and for men (but not women), preference for sexual exclusivity correlate with higher intelligence, a new study finds.

Scientists have pinpointed how a key hormone helps animals to recognize others by their smell. Researchers at the University of Edinburgh have shown that the hormone vasopressin helps the brain differentiate between familiar and new scents.

A paralyzed patient implanted with a brain-computer interface device has allowed scientists to determine the relationship between brain waves and attention. Characteristic activity patterns known as beta and delta oscillations have been observed in various regions of the brain since the early 20th century, and have been theoretically associated with attention. The unique opportunity to record from human motor cortex allowed University of Chicago researchers to investigate this relationship more thoroughly than ever before.

The human brain is a big believer in equality -- and a team of scientists from the California Institute of Technology and Trinity College in Dublin, Ireland, has become the first to gather the images to prove it.Specifically, the team found that the reward centers in the human brain respond more strongly when a poor person receives a financial reward than when a rich person does.

The human brain excels at using past experiences to make predictions about the future. However, the world around us is constantly changing, and new events often violate our logical expectations. "We know these unexpected events are more likely to be remembered than predictable events, but the underlying neural mechanisms for these effects remain unclear," says lead researcher, Dr. Nikolai Axmacher, from the University of Bonn in Germany.

Schizophrenia is an incredibly complex and profoundly debilitating disorder that typically manifests in early adulthood but is thought to arise, at least in part, from pathological disturbances occurring during very early brain development. Now, a new study published by Cell Press in the Feb. 25 issue of the journal Neuron, manipulates a known schizophrenia susceptibility gene in the brains of fetal mice to begin to unravel the complex link between prenatal brain development and maturation of information processing and cognition in adult animals.

Researchers from Columbia University and the National Heart, Lung and Blood Institute have determined that an imaging exam of the heart using the latest generation of CT technology exposes patients to as much as 91 percent less radiation than standard helical CT scanning.

Annual breast cancer screening with both mammography and magnetic resonance imaging is likely to be a cost-effective way to improve life expectancy in women with an increased risk of breast cancer, according to a new study. The findings support current American Cancer Society screening recommendations.