Phase 1 · Understand the Body — Why the disease behaves the way it does.
The One-Line Truth
The whole disease in one chain
Everything on this page exists to explain this line.
The brain suddenly stops thinking clearly and the confusion comes and goes within hours, almost always because something fixable—medicine, infection, dehydration, or broken chemistry—is attacking the brain right now.
Air Traffic Control Tower Under Attack
Your brain is like an air traffic control tower that keeps planes (thoughts) landing and taking off smoothly all day. The tower needs steady electricity (oxygen and glucose), clear radio signals between controllers (neurotransmitters like acetylcholine and dopamine), and controllers who are awake and alert (reticular activating system firing properly). When delirium hits, it's like someone suddenly cuts the power, jams the radios, or slips the controllers sleeping pills—so planes start crashing into each other, some land on the runway twice, and the tower loses track of what's in the air. The controllers (your attention and memory centers) can't do their job anymore because the fuel and signals they depend on are broken. Unlike a tower that's permanently closed (dementia), this one can restart immediately if you restore the power, fix the radios, and wake up the controllers—but if you wait too long, planes keep crashing and some wreckage becomes permanent.
American Geriatrics Society 2015 Beers Criteria and Delirium Guidelines · NICE Guideline NG103: Delirium (2019) · Society of Critical Care Medicine: Clinical Practice Guidelines for Pain, Agitation, Delirium (2018) · American Psychiatric Association DSM-5-TR · reviewed 2026-07-07