The authors measured motor evoked potentials (MEPs) elicited by single pulse transcranial magnetic stimulation (TMS) in 10 volunteers, and in 2 patients with multiple sclerosis (MS) with temperature dependent neurological symptoms. Three sites were stimulated - the motor cortex, the brainstem, and a spinal nerve. The MEPs were measured before and after 30 minutes exposure to a 800 MHz cell phone at an average power of 0.8 W.

No effects were seen in the normal volunteers or in the MS patients from the cell phone exposure.