People in a vegetative state generally have no awareness, thoughts, or conscious experience, appearing awake but lacking purposeful response; however, advanced brain scans reveal a small minority retain hidden awareness, experiencing a "locked-in" state where they understand but cannot communicate, facing potential frustration, pain, or even happiness if they can connect with loved ones, highlighting a critical distinction from true unconsciousness.
Most people in a vegetative state have lost all capacity for awareness, thought, and conscious behavior. However in a few people, functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) have detected evidence of some brain activity suggesting possible awareness.
However, a person in a vegetative state doesn't show any meaningful responses, such as following an object with their eyes or responding to voices. They also show no signs of experiencing emotions nor of cognitive function.
They also can't speak their thoughts or express desires to anyone. Moreover, those in a vegetative state show no signs of understanding or emotion.
May moan or make other sounds, especially when tight muscles are stretched. May cry or smile or make other facial expressions without a clear cause. May briefly move eyes toward people or things but these looks are not sustained.
Conclusion. Continuing artificial life support for patients who are brain dead may produce harm to patients, families, and others involved. Declaration of brain death should not be delayed to wait for families or to justify hospital care. Instead, appropriate family care should be provided after the death declaration.
People in a vegetative state can: Open their eyes and blink. Sleep and wake up on a regular schedule. Do basic automatic movements, such as breathing, sucking, chewing, gagging, coughing, and swallowing.
Even though those in a persistent vegetative state lose their higher brain functions, other key functions such as breathing and circulation remain relatively intact. Spontaneous movements may occur, and the eyes may open in response to external stimuli. Individuals may even occasionally grimace, cry, or laugh.
Other studies have shown that up to 20 percent of patients in various vegetative states can hear and respond on at least some level. But at least some of the responses seen could be dismissed as simple reflexes, or at best akin to someone in a dream state responding to stimuli.
Recovery among vegetative patients is so rare, Owen hesitates to use the word. “People get the wrong idea,” he says. Some others have recovered, including the first vegetative patient he ever put into a brain scanner, in 1996.
It's important to distinguish brain death from a coma or a vegetative state. In a coma, there is still some brain activity, and the individual may have the potential for recovery. In a vegetative state, there might be partial brain function, but the person lacks awareness and meaningful responsiveness.
Patients in a vegetative state may have awoken from a coma, but still have not regained awareness. In the vegetative state patients can open their eyelids occasionally and demonstrate sleep-wake cycles, but completely lack cognitive function. The vegetative state is also called a "coma vigil".
The main symptom of a vegetative state is a lack of consciousness. People in this state don't show the usual signs of consciousness, such as being able to speak, respond to commands, move with purpose, or avoid painful stimuli.
Hypoxic Brain Injury
In most cases, the injury is caused by a medical incident or emergency, such as a heart attack or stroke. If an individual does not receive immediate medical attention or help to restore oxygen flow, the brain suffers irreversible damage, possibly leading to death.
Coma is a state of unarousable unresponsiveness. A coma is a deep state of eyes-closed unconsciousness where a person is not able to respond to people or the environment around them. In a coma, a patient is alive and there is some brain activity.
I've written a news story for New Scientist about a recent study which shows that patients in the minimally conscious state may be capable of dreaming, and that studying the brain wave patterns associated with sleep could be helpful in distinguishing minimally conscious patients from those in the vegetative state.
During this time, they aren't aware of themselves or the world around them. A state of complete unconsciousness with no eye-opening is called coma. A state of complete unconsciousness with some eye-opening and periods of wakefulness and sleep is called the vegetative state (VS).
When a patient is in a comatose state, he/she does not demonstrate any signs of communication or communication attempts. When a patient is in a vegetative state, he/she may demonstrate oral reflexive movement and reflexive voicing.
In a study by Demertzi and colleagues (19), 2,059 medical and paramedical professionals from 32 European countries were asked the following question: “can a patient in vegetative state feel pain?” Over 40% of those surveyed replied that these patients do not feel pain.
Patients may smile, grimace, cry, grunt, or groan while awake, and families will often take these as signs of pain and pleasure. But their doctors usually remain skeptical, suspecting these behaviors are merely reflexes.
Symptoms
Patients may have complex reflexes, including eye movements, yawning, and involuntary movements to noxious stimuli, but show no awareness of self or environment.
The three essential findings in brain death are coma, absence of brainstem reflexes, and apnoea.
Some factors that may trigger brain damage that leads to a vegetative state are: Traumatic brain injury, such as when it is caused by traffic accidents. Disorders that lead to brain oxygen deficiency, such as myocardial infarction, hypoxic-ischemic encephalopathy, and many others.