Reliable detection of low visual acuity in mice with pattern visually evoked potentials

Area of Science:

• Neuroscience
• Ophthalmology
• Vision Science

Background:

• Optokinetic response (OKR) is a common method for assessing visual function in mice.
• Pattern visually evoked potential (pVEP) is an electrophysiological technique to record visual cortex neuron responses to patterned stimuli.

Purpose of the Study:

• To optimize conditions for recording pVEPs in wild-type mice.
• To compare the sensitivity of pVEP and OKR in measuring visual acuity, especially in low-vision models.

Main Methods:

• Investigated optimal electrode depth (1, 2, or 3 mm) for pVEP recording.
• Tested optimal stimulus patterns (vertical, horizontal, oblique stripes, checkerboard).
• Compared pVEP and OKR measurements in wild-type and optic nerve crush-induced low-vision mice.

Main Results:

• Optimal pVEP conditions (2 mm depth, vertical stripes) yielded higher visual acuity (0.530 ± 0.021 cycle/degree) than OKR (0.455 ± 0.006 cycle/degree).
• pVEPs reliably quantified residual vision (0.064 ± 0.004 cycle/degree) in low-vision mice, whereas OKR failed.
• pVEPs demonstrated greater sensitivity in measuring visual function compared to OKR.

Conclusions:

• Optimized pVEP recording provides a more sensitive measure of visual function in mice.
• pVEP is particularly valuable for assessing visual acuity in mouse models of ocular disease and low vision.
• This technique enhances the study of visual deficits in preclinical research.