Keith Burgess-Jackson, J.D., Ph.D.

To the Editor:

Your July 19 front-page article relating cellphone conversation to increased probability of auto accidents relied on anecdotal data with a sprinkling of accident statistics. A follow-up article (front page, July 21) briefly mentioned a number of scientific studies demonstrating impaired brain function during cellphone conversations, whether hands-free or hands-on.

We would like to point out that it is studies of brain function that solidify the case against the cellphone.

For example, in our lab we have conducted functional magnetic resonance and magnetoencephalography studies during hands-free phone conversation using a film simulating driving. (Magnetoencephalography is a functional brain imaging technique with millisecond time resolution and millimeter spatial resolution.)

We showed that during hands-free phone conversation there was decreased activity in the right parietal area (an area involved with multitasking) and increased reaction time. The observed changes in brain function are independent of the design features of the phone.

Susan Bowyer
John Moran
Norman Tepley
West Bloomfield, Mich., July 21, 2009
The writers are senior scientists at the Henry Ford Hospital, Detroit. Dr. Tepley is also scientific director of the Neuromagnetism Lab.

Note from KBJ: This argument proves too much. It proves that there should be no passengers. The problem with cellphones is not that they're engrossing; it's that they require handling.