Horner’s syndrome

a condition characterized by partial ptosis (drooping of the upper eyelid), miosis (excessive constriction of the pupil), and often anhidrosis (absence of sweating) on the same half of the face. Congenital or acquired, it is caused by damage to the pons region of the brainstem. There may be lack of coordination in eye movements (saccades and smooth-pursuit eye movements). Also called oculosympathetic paralysis. [Johann Horner]

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

January 20th 2025

London syndrome

explicit and constant resistance and refusal by hostages to do what captors expect during a hostage situation, first identified in 1981 after a hostage-taking incident in London. It may result in serious injury and death to the resistors.