If looking at the sun or a light bulb makes you sneeze, then you carry the gene for the photic sneeze reflex, or—as it’s called by some clever otolaryngologists—autosomal dominant compulsive helio-ophthalmic outbursts of sneezing (ACHOO). Doctors think the light directly or indirectly stimulates the trigeminal nerve that runs to the face and mucus membrane, accidentally setting off a sneeze response in the process.

READ MORE: Why Light Makes You Sneeze