This study attempted to establish a connection between the exposure of a specific area of the brain and the cognitive functions associated with that area. Cognitive tasks were chosen according to the brain side they are assumed to activate.
Each subject had two standard Nokia 5110 GSMcellular phones attached to both sides of his head by a non-conductive frame. The cellular phonespower was controlled by using an HP GSM test system model E6392B. The phones were operated with test SIM cards. This system maintained the phones at either no transmission or full power transmission. The communication between the phones and the test system was wireless, at an extremely small output power (0.01 mW peak), which is considered negligible. During the experiment, the phones were battery operated.
The test was divided into two sessions: a first 1 h series of tasks, a 5 min break, and then another hour of tasks. All subjects performed all four tasks under either, left, right, or sham exposure conditions. This resulted in 12 sub-sessions per subject. Each subject performed a total of 1614 trials in all four experiments.
The data indicated that the exposure of the left side of the brain slows down the left-hand reaction time. This effect was apparent in three of the four tasks, but it was highly significant in only one of the tests (in the spatial item recognition task). This effect became evident only in the second part of the experiment (after an hour of test, of which 40 min were under full exposure). The exposure intensity and its duration exceeded the common exposure of mobile phone users.