June 22, 2005 -- Halle Berry and Jennifer Aniston often appear on magazine covers, but now they're in new territory -- the pages of the journal Nature and perhaps even your own brain.
The stars -- along with Julia Roberts and Kobe Bryant -- didn't team up for a new movie or public service ad. Instead, their images, or even only their names, got top billing in the latest project by Rodrigo Quian Quiroga, PhD.
Quiroga isn't a hot new director in Hollywood. He's a bioengineering lecturer at England's University of Leicester. Quiroga worked on the study while at the California Institute of Technology (Caltech) and UCLA.
Quiroga and colleagues watched single brain cells rev up when people saw pictures of certain celebrities or famous landmarks, like the Sydney Opera House or Italy's leaning tower of Pisa. The findings may cast brain cells in a new light.
The researchers looked at how our brains process visual information and long-term memory. They also looked at what role different brain regions and cells play in decoding images.
Star Power Meets the Brain
The study had nothing to do with epilepsy. Instead, the electrodes came in handy for another purpose. The patients agreed to let the electrodes be used to monitor individual brain cells or brain regions while the images were shown.
Everyone was a bit different. They had electrodes in different parts of an area of the brain related to memory and one of the first brain areas to falter when Alzheimer's disease strikes.
In one person, electrode readings spiked in a single brain cell when images related to Halle Berry came up. For another person, an electrode in a different location fired up when pictures of Jennifer Aniston were shown. Someone else had a brain cell that responded to images of the Sydney Opera House.
Picky, Picky, Picky
The individual brain cells were quite specific about the images to which they responded. For instance, the cell that responded to pictures of Jennifer Aniston couldn't care less about images that also included Brad Pitt.
The neuron fixated on Halle Berry responded to her Catwoman movie costume and even the letters of her name. But when Catwoman images unrelated to Berry were shown, the cell didn't take the bait. It didn't respond the same way it had for all things Berry.
Other individual brain cells responded selectively to images of animals (spiders, seals, or horses) or specific foods, say the researchers.
Defying a Stereotype
Obsession with celebrity wasn't the study's point. Instead, the scientists wanted to learn more about how the brain recognizes images with lightning-fast speed.
The findings may give the brain cell an image makeover. Apparently, brain cells, or neurons, have been typecast incorrectly, says researcher Christof Koch, PhD, in a news release.
"Our findings fly in the face of conventional thinking about how brain cells function," says Koch, a Caltech professor of computation and neural systems. "Conventional wisdom views individual brain cells as simple switches or relays," he says. "In fact, we are finding that neurons are able to function more like a sophisticated computer."
"This new understanding of individual neurons as 'thinking cells' is an important step toward cracking the brain's cognition code," says Itzhak Fried, MD, PhD, in the news release.
"As our understanding grows, we one day may be able to build cognitive prostheses to replace functions lost due to brain injury or disease, perhaps even for memory," says Fried, a UCLA professor of neurosurgery, psychiatry, and behavioral sciences.
The responses may have been based more in memory than vision, and emotions about the images could also be involved, say the researchers.
In a Nature editorial, Charles Connor, PhD, writes that he doubts that anyone would have predicted such a striking confirmation at the level of individual neurons. Connor works in Johns Hopkins University's neuroscience department and the Zanvyl Krieger Mind/Brain Institute.