Preparing a Rat Model to Assess Visual Pathway Integrity Using an Electrophysiology Setup

Light stimulates the eye's photoreceptors, sending electrical signals to the visual cortex in the brain to process visual information.

To measure the integrity of this visual pathway, start with an anesthetized, dark-adapted rat in a dark room.

Position a reference VEP electrode around the rat's lower front teeth.

Secure the rat with a fastener strip on an ERG platform in front of a Ganzfeld bowl, a light-illuminating device within a Faraday cage.

Place the reference ERG electrodes around the eye's equator, encircling the scleral ring, and secure them.

Then, attach the VEP active electrodes to the pre-implanted skull screws to detect cortical signals.

Position the ERG electrodes with lubricant on the center of the eyes to measure their responses to light stimuli.

Remove excess lubricant and insert a ground electrode into the tail to reduce electrical noise.

Move the ERG platform closer to the Ganzfeld bowl and close the Faraday cage to minimize external interference.

For scotopic recordings, all the procedures are performed in a dark room. For illustration purposes, electrode positioning is conducted under normal room lighting here. The animal was dark-adapted for 12 hours, and ane