Constant darkness throws a molecular switch in mammals that shifts the body's fuel consumption from glucose to fat and induces a state of torpor in mice, a research team led by scientists at The University of Texas Medical School at Houston reports in the Jan. 19 edition of Nature.

By tracing the 30-million year history of variation in a gene found in plants such as tomatoes and tobacco, biologists at the University of California, San Diego have found new evidence to support an old idea -- that some evolutionary changes are irreversible.

When a human looks at a number, letter or other shape, neurons in various areas of the brain's visual center respond to different components of that shape, almost instantaneously fitting them together like a puzzle to create an image that the individual then "sees" and understands, researchers at The Johns Hopkins University report.

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), today announced that enrollment into a large international HIV/AIDS trial comparing continuous antiretroviral therapy with episodic drug treatment guided by levels of CD4+ cells has been stopped. Enrollment was stopped because those patients receiving episodic therapy had twice the risk of disease progression (the development of clinical AIDS or death), the major outcome of the study.

Just imagine listening to someone talk and also hearing the buzz of the overhead lights, the hum of your computer and the muffled conversation down the hallway. To focus on the person speaking to you, your brain clearly can't give equal weight to all incoming sensory information. It has to attend to what is important and ignore the rest.

A group of Northwestern University researchers is developing a novel gene therapy aimed at selectively turning off one of the genes involved in the development of Parkinson's disease.

Instantly reacting to the sweet lure of chocolate or the bitter taste of strychnine would seem to demand that such behavioral responses be so innate as to be hard-wired into the brain. Indeed, in studies with the easily manipulable fruit fly Drosophila, Kristin Scott and colleagues reported in the January 19, 2006, issue of Neuron experiments demonstrating just such a hard-wired circuitry.

Non-coding regions of the genome – those that don't code for proteins – are now known to include important elements that regulate gene activity. Among those elements are microRNAs, tiny, recently discovered RNA molecules that suppress gene expression.