Date: July 1st, 2026 5:34 AM
Author: Ricky
cr one of the absolutely worst most nightmarish ways to see someone die at the very end for anyone thats witnessed it in a relative:
"When Alzheimer’s disease reaches its terminal stage, the neurodegenerative process eventually spreads from the cerebral cortex and hippocampus (the areas responsible for memory, thought, and personality) down into the brainstem.
The brainstem is the body's control tower for autonomic, life-sustaining functions. When it begins to shut down, the body loses its ability to regulate itself, leading to a predictable progression toward death.
Here is a breakdown of how this process unfolds and what it looks like structurally and clinically.
The Neurodegenerative Path to the Brainstem
In advanced Alzheimer's, the accumulation of amyloid plaques and neurofibrillary tangles (tau proteins) destroys the vast majority of neurons in the higher brain. As the disease advances to the very end, this destruction moves into the deep, ancient structures of the brainstem: the midbrain, pons, and medulla oblongata.
The medulla oblongata, in particular, houses the cardiac, respiratory, and vasomotor centers. As these neurons misfire and die, the body's automatic systems begin to fail.
The Clinical Process of Brainstem Shutdown
As the brainstem loses its grip on autonomic regulation, the body undergoes specific, sequential changes over the course of days to hours:
1. Loss of Swallow Reflex and Nutrition Intake
One of the first signs of brainstem compromise is the loss of the basic, involuntary reflex to swallow.
The Impact: The individual can no longer safely manage food, liquids, or saliva. Attempting to feed at this stage can cause aspiration (food or fluid entering the lungs).
2. Failure of the Respiratory Center (The Medulla)
The brainstem tells our lungs when to breathe based on carbon dioxide levels. When the medulla fails, breathing becomes erratic and goes through distinct phases:
Cheyne-Stokes Respiration: This is a characteristic pattern where breathing gets deeper and faster, then becomes very shallow, followed by a period of apnea (no breathing at all) that can last from 10 to 60 seconds.
The "Death Rattle": Because the swallow reflex is gone, secretions pool at the back of the throat. As air passes through these secretions, it creates a gurgling sound.
3. Cardiovascular and Vasomotor Instability
The vasomotor center in the brainstem controls blood pressure and heart rate by signaling blood vessels to constrict or dilate.
The Impact: Blood pressure drops significantly, and the pulse becomes weak and irregular.
Mottling: Because the brainstem is prioritizing blood flow to the core vital organs, peripheral circulation fails. The hands, feet, and knees will become cold to the touch and develop a purplish, marbled appearance (mottling).
4. Loss of Consciousness and Reflexes
The brainstem contains the Reticular Activating System (RAS), which regulates wakefulness and consciousness. As it shuts down:
The individual slips into a deep, comatose sleep.
They become completely unresponsive to external stimuli, including sound or touch.
Basic brainstem reflexes, such as the pupillary response to light or the blink reflex, disappear entirely.
The Final Moments
Ultimately, the brainstem stops sending signals to the diaphragm altogether. The final breath is typically followed by a long pause, and because the cardiac center in the medulla has ceased firing, the heart slows to a stop within a few minutes.
From a clinical standpoint, because the higher brain structures have already been significantly degraded by Alzheimer's, the final shutdown of the brainstem the body simply stops receiving the commands it needs to run."
(http://www.autoadmit.com/thread.php?thread_id=5878518&forum_id=2)#49972915)