Phosphene

Neuroscience

Retina

Retinitis pigmentosa

Computer science

Stimulation

Optogenetics

Medicine

Ophthalmology

Visual prosthesis

Visual system

Transcranial magnetic stimulation

Retinotopy

Retinal Prosthesis

Retinal implant

Retinal

Psychology

Optic nerve

Channelrhodopsin

Fundus (uterus)

Scientific Reports

Degenerative retinal diseases such as retinitis pigmentosa and macular degeneration cause irreversible vision loss in more than 10 million people worldwide. Retinal prostheses, now implanted in over 250 patients worldwide, electrically stimulate surviving cells in order to evoke neuronal responses that are interpreted by the brain as visual percepts (‘phosphenes’). However, instead of seeing focal spots of light, current implant users perceive highly distorted phosphenes that vary in shape both across subjects and electrodes. We characterized these distortions by asking users of the Argus retinal prosthesis system (Second Sight Medical Products Inc.) to draw electrically elicited percepts on a touchscreen. Using ophthalmic fundus imaging and computational modeling, we show that elicited percepts can be accurately predicted by the topographic organization of optic nerve fiber bundles in each subject’s retina, successfully replicating visual percepts ranging from ‘blobs’ to oriented ‘streaks’ and ‘wedges’ depen...

A model of ganglion axon pathways accounts for percepts elicited by retinal implants