The hype has increased in the last few decades since functional neuro-imaging has enabled scientists to observe directly the activity in the brains of conscious subjects exposed to certain stimuli or engaging in different tasks.
"We were able to reveal dream content from brain activity during sleep, which was consistent with the subjects' verbal reports, " explained Professor Kamitani.
They're interested only in their subjects' brains, which are abuzz with electrical activity, recorded as rows of squiggly lines crawling across the screen of a Dell laptop.
The research subjects answered specific detailed questionnaires regarding aspects of their physical activity, and the researchers were able to determine how much energy they expended according to the distance they reported running or walking.
Compared with subjects whose phones were turned off, the group whose phones were on had "significantly higher" brain activity in the area closest to the telephone antenna.