Action Potential bandwidth

Richard Norman rsnorman at
Mon Aug 21 08:31:03 EST 2000

"Iain McClatchie" <iain at> wrote in message
news:39A0A540.4D42D59F at

< the argument so far -- ion channels act as quasi-independent
      computational elements interacting through the exchange of

> Finally, I have only vague guesses at the frequency of light used.
> Dropping an ion across 100 mV is enough energy for a 12 micron photon,
> which is way deep infrared.  Maybe multiple ions get dropped across
> the voltage to successively pump the emitting electron to higher and
> higher energies, in which case the wavelength used could be nearly
> anything.

The real problem with this idea really lies in a 50 year history of
phenomenal success for the traditional ionic theory.  All the studies, from
early voltage clamp and radioactive tracer studies of ion currents and
through patch clamp, and molecular biology of channel structure
indicate that ions move in a dissipative flow by electrochemical diffusion
through essentially water filled channels, although with some local
interaction with ion selectivity sites in the channel.  There is no
for the energy released to be coupled to any other process without
significantly interfering with measured flow rates.

Not to mention that the known structure of ion channels immediately
suggests the validity of the ionic theory and in no way offers any feature
to suggest such a radically different concept.  Any photon emission and
absorption sites coupled to ion movement would be prominent and
unusual features of the protein structure of the channel.

Theory is a lot of fun, but in the end, physiology is an experimental

> -Iain McClatchie                            650-364-0520 voice
>                       650-364-0530 FAX
> iain at                             650-906-8832 cell

More information about the Neur-sci mailing list