The line between life and death has been blurred by medicine for some time. When, exactly, a person stops being a mind and reverts to a bundle of random reflexes, is determined in a lot of ways, including an electroencephalogram.
But you can't make that determination only based on an electroencephalogram, because an EEG declares gelatin to be legally alive.
As our ability to prolong technical life increases, there is bound to be some debate about when it's okay to allow the heart to stop beating. This is the kind of debate that will never actually end, but at least it had an interesting beginning.
An electroencephalogram, or EEG, machine measures the tiny electric impulses that active neurons make in the brain. Different frequencies and patterns are normal for different levels of consciousness, and EEGs have been used to diagnose sleep disorders and seizure disorders, as well as to identify and track brain injuries and neurodegenerative diseases. They have also been used as one of the ways to determine whether or not unresponsive patients still have enough brain activity to qualify as alive. They were never used exclusively, which is good — because in 1974, Doctor Adrian Upton used them to demonstrate that gelatin could give off enough brain power to qualify as alive.
As The Straight Dope explains, this demonstration was very much geared to catch public attention and help inform people more about how the brain, and ways of measuring it, worked. Upton had tried the exact same demonstration with regular gelatin in 1969, without much attention. For the 1974 experiment he used a molded dome of lime jell-o, which he thought was more photogenic and more popular than regular gelatin.
The use of the gelatin at all was a kind of stunt in and of itself. Doctors already knew that the sensitive machine could pick up electrical signals from heartbeats and muscle movement, as well as other machines in the room. Before measuring a patient, they often attached an EEG to a resistor in order to determine the background level in a room before measuring a patient. Jell-o was much the same thing — except that even a skeptic could understand that it wasn't performing any sneaky technical manipulation of the EEG machine the way a more technically advanced object might.
Attaching an EEG to jell-o produces things that look like alpha waves, which are the waves that an awake human will produce, as long as they're resting and have their eyes closed. The waves that the gelatin produces are much, much smaller in amplitude, and so a person would have to be extremely sick in order to get down to the electrical activity that might be read from gelatin. When they do get that bad, however, there are different tests to determine responsiveness.
And this is the point that Upton was trying to make. There is no one test that can determine if a person has, effectively, died. Doctors have a number of tests they do to determine if a person is responsive physically. They'll tap the jaw, and see if the face moves. They'll see if the pupils react to light, the eyes move with the person (instead of staring straight up like dolls' eyes), if they blink, if they react to having cold water in their ear, or if they cough when their throat is stimulated. After that, the doctors will determine brain function with an EEG, determine blood flow in the brain with an MRI, and end by figuring out the overall pressure in the brain. Brain death is, essentially, the declaration that all systems are not responsive. So it's unlikely that you'll be mistaken for jell-o anytime soon.
Second Image: Gisela Francisco