The researchers reported in the April 20, 2006, issue of Neuron the results of reading, language, and object recognition tests both before and after the surgery on the 46-year-old man. They found his reading capability before surgery to be normal. However, tests after surgery showed very different results.

"Although we studied reading more extensively than the perception of other types of visual stimuli, our patient presented a clear-cut reading impairment following surgery, while his performance remained flawless in object recognition and naming, face processing, and general language abilities," reported the researchers.

"Such selectivity may be difficult to observe in patients with more customary lesions resulting from strokes or tumors, which often affect a larger extent of cortex and white matter. The small size of the present lesion thus provides precious support to the idea of partial regional selectivity for word perception in the ventral cortex," they wrote.

Importantly, the researchers observed that before the surgery, the patient could recognize long words as quickly as short ones; but after the surgery, the recognition time increased linearly as a function of word length. Such findings indicated that the patient had been reduced to recognizing words letter by letter.

"How could there be a piece of neural tissue dedicated to a recently invented cognitive skill like word recognition?" wondered Alex Martin in a preview of the paper in the same issue of Neuron.

Nevertheless, Martin commented, Cohen and his colleagues "report a unique set of findings in favor of the existence of the VWFA that will surely add fuel to the debate." He concluded that "The single case study...provides compelling evidence that the VWFA plays a causal role in the chain of neural events that underlie normal reading."

"The lid on the correcting engine KD-2 did not fully open during the maneuver, so we decided to cancel the operation," an official in the mission control center near Moscow said as quoted by the ITAR-TASS news agency.

Experts were trying to establish what went wrong before attempting to re-start the operation on Friday, the official said.

The ISS crew, US astronaut Jeffrey Williams and Russian cosmonaut Pavel Vinogradov, "were not asleep when that happened, and it was they who noted the failure as the maneuver was being prepared for," the official added.