Related Experiment Video
Updated: Jul 9, 2026
08:22
Application of Optical Coherence Tomography to a Mouse Model of Retinopathy
Published on: January 12, 2022
Pulfrich's phenomenon in optic nerve hypoplasia
Gordon Heron1, Gordon N Dutton, Daphne L McCulloch
1Department of Vision Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow, G4 OBA, UK. ghe@gcal.ac.uk
Summary
Mild optic nerve hypoplasia (ONH) can cause visual disturbances like the Pulfrich effect, even with normal vision. Tinted glasses effectively corrected these perceptual errors in a pediatric case.
Area of Science:
- Ophthalmology
- Neuroscience
- Visual Perception
Background:
- Optic nerve hypoplasia (ONH) is a congenital condition characterized by reduced retinal ganglion cells and optic nerve axons.
- ONH can lead to a spectrum of visual deficits, from severe impairment to normal vision in mild cases.
Observation:
- A 12-year-old girl with mild ONH experienced visual symptoms including veering and bumping into objects, consistent with the Pulfrich effect.
- She perceived a clockwise elliptical path when tracking a pendulum, indicating a left-sided Pulfrich effect.
Findings:
- Ophthalmic examination revealed asymmetry in optic nerve dimensions, with the left nerve being smaller.
- Despite normal visual acuity, visual fields, color vision, and stereopsis, a small inter-ocular latency difference (0.88 ± 0.55 ms) was measured.
- Pattern electroretinography (PERG) showed a borderline reduction in the affected eye.
Implications:
- This case demonstrates that mild ONH can manifest with perceptual visual disturbances like the Pulfrich effect, despite preserved standard visual functions.
- The use of a tinted lens in glasses successfully neutralized the Pulfrich effect, offering a simple corrective strategy.
Related Concept Videos
01:20Anatomy of the Eyeball
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...
01:22Photoreceptors and Visual Pathways
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...