  Recently, we have proposed a redox molecular hypothesis about the natural
biophysical substrate of visual perception and imagery (B\'okkon, 2009.
BioSystems; B\'okkon and D'Angiulli, 2009. Bioscience Hypotheses). Namely, the
retina transforms external photon signals into electrical signals that are
carried to the V1 (striate cortex). Then, V1 retinotopic electrical signals
(spike-related electrical signals along classical axonal-dendritic pathways)
can be converted into regulated ultraweak bioluminescent photons (biophotons)
through redox processes within retinotopic visual neurons that make it possible
to create intrinsic biophysical pictures during visual perception and imagery.
However, the consensus opinion is to consider biophotons as by-products of
cellular metabolism. This paper argues that biophotons are not by-products,
other than originating from regulated cellular radical/redox processes. It also
shows that the biophoton intensity can be considerably higher inside cells than
outside. Our simple calculations, within a level of accuracy, suggest that the
real biophoton intensity in retinotopic neurons may be sufficient for creating
intrinsic biophysical picture representation of a single-object image during
visual perception.
