>> guest: bovary recruited initially 48 subjects and they were brought into the laboratory and testing was done to assure that they were controlled. all of the subjects had history of cell phone exposure. they were tested on two different days and the order of the days was randomized. on every given day the subject had to cell phones place, what on the left someone on and one on the right and these were secured i a muffler to ensure positioning. the upper parts of the cell phone was to the air in the lower part was to the mouth. the subject did not know whether the cell phones were off or on, nor did they know whether they're right or the left cell phone would be on. this was done because we did not want -- if i have a cell phone here i may have prior to my experience with using cell phones make me alert to try to figure out something that could confound the results. in order to control for expectations we put two cell phones and perhaps the subjects the first day the right phone was on and for the other half, that first day, both phones were off. we started the activity with the phone