Alice in Wonderland Syndrome

Alice in Wonderland syndrome, also called Todd's syndrome or dysmetropsia, is a neurological condition that distorts a person's perception of their own body and of the objects around them, most often causing macropsia, in which objects appear far larger than their actual size, or micropsia, in which objects appear far smaller, along with distorted perceptions of distance, shape, time, or sound; episodes typically last from a few minutes to about an hour, may involve dizziness, nausea, depersonalization, or auditory hallucinations, and affected people generally remain aware throughout that their perceptions are being distorted. The British psychiatrist John Todd formally described and named the condition in 1955 after Lewis Carroll's 1865 novel Alice's Adventures in Wonderland, in which the title character repeatedly experiences dramatic changes in her own perceived size, though the American neurologist Caro Lippman had already documented similar cases in 1952; Todd went on to theorize that Carroll himself may have experienced migraine-related visual distortions of exactly this kind, which then inspired the story. The exact cause remains unidentified in more than half of documented cases, but migraine is the most common identified association, affecting roughly one in ten people who experience migraines, and viral infections, particularly Epstein-Barr virus infection, along with head trauma and abnormal brain electrical activity in the visual processing regions, are also recognized triggers; the syndrome occurs more often in children and young adults, with an average age of onset around six years old.