The Queens man on trial for

shooting NYPD Officer Brian Moore

suffers from a seizure-related psychosis that leaves him delusional and paranoid, a defense expert testified Wednesday.

Accused cop killer Demetrius Blackwell had a seizure the night before he fatally shot the 25-year-old cop in May 2015, clinical neuropsychologist Dr. Sarah Schaffer told Queens Supreme Court jurors.

Schaffer said Blackwell often had seizures that made him “combative, aggressive [and] violent to the point of injuring hospital workers.”

Moore was killed responding to a call that Blackwell was tossing bricks through a neighbor’s window.