Comparing flickering and pulsed chromatic pupil light responses

Protocols for chromatic pupil light reflex (PLR) testing considered mostly pulsed stimulation (pPLR). A more sophisticated and promising technique is based on the PLR to flickering stimulation (fPLR). Our aim was to compare fPLR and pPLR parameters in order to validate fPLR paradigm. Two different experiments were carried out in young participants to compare parameters of chromatic pupillary measurements under flickering and pulsed conditions. We found that the fPLR amplitude parameter was significantly associated with pPLR transient constriction parameter. Also, for some conditions, typical pulse parameters can be identified directly in the fPLR recordings.