Peri-somatic modulation of diffracted light and its variation with consciousness

Existing noninvasive neurophysiological recording methods, such as electroencephalography, magnetoencephalography and functional magnetic resonance imaging, can acquire neural correlates of consciousness, but they cannot mechanistically differentiate between conscious and unconscious states. Here we describe a method that detects a new physical effect of apparent neural origin in the peri-somatic space using a newly developed instrument and test whether it might allow such differentiation. This effect is a slow decrease in the intensity of diffracted low power laser light emitted within a photoelectronic instrument placed close to the body of an awake subject. It is markedly attenuated by general anesthesia in mice and unconsciousness in patients. Its direction is reversed when the instrument is exposed to live invertebrates or to the decapitated head of a euthanized mouse. We provide evidence to rule out all plausible nonspecific physical and non-biological explanations for the photo-modulatory effect in our estimation, such as those arising from thermodynamic and electromagnetic influences. We have also been able to record it in a near-complete vacuum. These findings point to the existence of a previously unrecognized biophysical phenomenon that appears to be related to a mechanism underlying consciousness.