# Photoreceptor
**Collection:** [[collections/Neurotech|Neurotech]]
**Type:** Sensory cell type
**Primary source:** [[articles/2026 Annual Report on Brain-Computer Interfaces|2026 Annual Report on Brain-Computer Interfaces]]
## Definition
A **photoreceptor** is a sensory cell that transduces light into biological signals.
## Relationships
- Photoreceptors form the input layer of visual circuits represented in fly connectomic datasets.
- The annual report identifies photoreceptor regions as difficult cases for a 2025 synapse-detection model.
- Photoreceptor segmentation quality affects downstream [[wiki/Synaptic Pathway|pathway]] and circuit analysis.