var items = new Array (new ImageMetaData('A portion of the hippocampus from a \'Brainbow\' transgenic mouse is shown in this undated handout image. U.S. researchers have manipulated neurons in mice to light up in a rainbow of fluorescent hues, creating a powerful tool for mapping out the brain\'s complicated wiring plan, they said on Wednesday. This "Brainbow," as they call it, will allow researchers to trace neurons throughout the nervous system, gaining new understanding of its organization and function. The multicolour \'Brainbow\' labeling reveals neurons of the CA1 area and their dendrites (pointing downward). REUTERS/Confocal microscopy courtesy of Tamily A. Weissman/Handout (UNITED STATES). NO ARCHIVES. NO SALES. \n','http://msnbcmedia.msn.com/i/msnbc/Components/Photo_StoryLevel/071031/071031-BRAIN-COLORS-vmed.jpg','3:52 p.m. ET, 10/31/07','Ho / Reuters','REUTERS',21565371));