Headlines
As reported by the Middletown Press, March 22, 2005.
Doctors Say Reaction of Brain Can Be Deceiving
By Abram Katz
We like to think of people being alert or unconscious, but the brain’s anatomy can render a deceptive state in between, doctors said.
Open eyes do not necessarily mean conscious or alert. And waking and sleeping do not always signify a normal cycle.
This is because the human brain is literally a complex simple organ.
Consequently, certain sections of the three-pound pinkish-gray seat of thought in the skull can be damaged beyond repair, while others continue to function, physicians said.
Terri Schiavo, the severely brain-damaged Florida woman at the heart of a flaring national debate on the nature of "life" appears to be awake in the snippets of videotape the public sees.
Some, who see the 41-year-old woman’s open blue eyes, head movements, and apparent response to voices, are convinced that her personality is alive and well right below the surface.
But, sadly, Schiavo is just the same as others who have suffered a devastating brain injury, said Dr. Hilary Onyiuke, chief of neurosurgery at the University of Connecticut Health Center.
What superficially seem to be signs of consciousness are really a function of the damaged brain’s two-tiered anatomy, he said.
The upper brain, or cerebral cortex, is where the mind plans, reasons, remembers and solves problems.
This is the grayish fissured tissue that we picture as "brain," and the place where alertness resides.
The brain stem, at the base of the organ, carries out "primitive functions" such as breathing, swallowing, respiring, and waking up and going to sleep, Onyiuke said.
If the cerebral cortex is irreparably damaged, but the lower brain survives, a patient like Schiavo displays primitive behaviors, he said.
However, the eyes are not focusing, the brain does not understand, and the patient cannot interact with her environment, he said.
Often the brain stem continues to function, but the patient’s eyes remain closed and she appears to be sleeping or dead.
Doctors are not sure why, but sometimes a person in a coma opens his eyes, yet re-mains in a deep coma, Onyiuke said.
Neurologists call this a "persistent vegetative state."
"To be in a persistent vegetative state is to be in a coma, but look like you’re awake," he said.
"This is very hard to understand," Onyiuke said.
Patients in full coma usually require a respirator to breathe. People in a persistent vegetative state can breathe by themselves.
"People in a persistent vegetative state are also able to maintain an open airway. They can cough," Onyiuke said.
All of this is controlled by the brain’s non-thinking autopilot.
Young patients are more able to reverse brain damage and recover, he said.
"When both hemispheres are completely damaged you can’t do anything," he said.
Schiavo apparently collapsed as a result of an electrolyte imbalance and blood flow to her brain was stopped for a few minutes.
Unlike other organs, the brain does not store glucose. After three minutes at zero blood pressure, permanent damage is inevitable, he said.
Dr. Phillip Brewer, senior attending physician at Yale-New Haven Hospital’s emergency department, said trauma specialists see unconsciousness, coma and persistent vegetative states.
When the cerebral cortex is overwhelmed by alcohol or other drugs, but not damaged, when the agents wear off the patient awakens from what is essentially a coma, he said.
"With a persistent vegetative state the reticular activating system in the lower brain keeps sending signals, but nothing is there to receive them, no consciousness," Brewer said.
However, this RAS control center responds to physical stimuli.
The most telling sign of brain status is an electroencephalogram.
An alert undamaged brain emits rapid spikes of electrical activity. The persistent vegetative patient’s waves are long, shallow and slow, he said.
Reflexes aside, nothing is happening, Brewer said.