Radiologists flex their ‘x-ray vision’

Practical experiments show that the average person filters out a great deal of visual information. Functional MRI studies suggest that radiologists' ocular systems become trained to sponge up that data.

Dr. Sven Haller and colleagues from the institute of neuroradiology at the University Hospital Basel in Switzerland investigated the differences in neuronal activity between 12 radiologists and 12 subjects with no image interpretation skills. They presented their findings at the 2005 European Congress of Radiology.

The researchers asked each group to indicate whether images presented to them were original or manipulated. Half of the images, which included radiographic and nonradiographic visuals, had been tampered with.

fMRI showed that the brains of radiologists reacted more strongly than those of the controls to radiological images. Radiologists processed all visual stimuli in a significantly different way.

"The most important finding is that we can document changes in neuronal activation due to learning. In other words, there must be neuronal plasticity in the adult brain," Haller said.

Radiological experience modifies neuronal representation in two ways:

• a modification in the neuronal processing for the trained stimulus, here radiographic images

• modification of nontrained stimuli, or the training of very specific stimuli modifying the neuronal system - here the visual system - in a general way

"Radiologists have learned by training to activate cortical areas more than the average person, which is important for 3D object recognition and manipulation," Haller said. "In general, we might infer that radiologists are more able to create a 3D representation of a presented object, which is of great help in image analysis."

Researchers did not test whether radiologists are faster than speeding bullets or more powerful than locomotives.

For more information from the Diagnostic Imaging archives:

fMRI documents risk anticipation center in the brain

Vivid imaginations trigger false memories

Functional MRI makes broader inroads into clinical practice

fMRI reveals zen of hitting the green