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The research
looked at the behaviour of 40 participants in their research. Twenty-four of
had to perform challenging
. These included looking at a computer screen and matching
letters that appeared. The other 16
did a similar, but easier task. Both teams worked for six hours, and had two ten-minute
. The researchers scanned the
of the participants. They found that the group who had the more difficult task had higher
of glutamate in their brain. Study author Antonius Wiehler said: "It would be great to find out more about how glutamate levels are restored." He asked: "Is sleep
? How long do breaks need to be to have a
effect?"