Visual electrophysiology provides an objective, quantitative means of assessing visual pathway function from the retina to the cortex1,2. Conventional tests such as full‑field electroretinography (ERG) and visual evoked potentials (VEPs) are widely used in clinical ophthalmology3,4. However, several specialized techniques with proven clinical value remain underutilized in routine practice.
Two such techniques are the photopic negative response (PhNR), a negative wave that follows the b-wave of the light-adapted electroretinogram (ERG) and reflects retinal ganglion cell function5,6, and the Baby Vision Test, a visual assessment modality that uses a dynamic target-based testing approach. The baby vision test uses a horizontally drifting grating (with luminance matched to the background) while recording eye movements. Spatial resolution is increased progressively, and visual acuity (VA) is estimated from the highest resolution that elicits stable tracking7. Although both techniques have demonstrated utility in research settings7,8, their widespread clinical adoption remains limited.
Several factors contribute to this gap. Electrophysiological recordings are susceptible to numerous confounds, including electromagnetic interference, grounding, electrode type and placement, stimulation parameters, patient factors (age, pupil, refraction, anesthesia), and environmental variables9,10,11,12. Procedural variability and lack of consistent reference data further undermine clinical confidence13.
To address these challenges, detailed, standardized workflows for PhNR and Baby Vision examinations are presented. These workflows are built upon a structured, checklist‑based 6E framework (Environment, Equipment, Examinee, Electrode, Examination, and Exit) that explicitly specifies environmental conditions, standardizes each testing phase from patient preparation to electrode placement, and translates technical parameters into practical, step‑by‑step actions. By reducing operator‑dependent variability and minimizing omitted steps, the 6E approach directly improves intra‑ and inter‑subject reproducibility compared to conventional, less protocol‑driven methods. The protocol is designed for routine clinical settings such as pediatric ophthalmology and electrophysiology laboratories. The aim is to facilitate broader clinical adoption of these valuable tools.