Neuroimaging Technology and the Future of Euthanasia

Terri Schiavo, a 26-year-old woman from Florida, suffered a cardiac arrest that cut off oxygen supply to her brain in 1990. She sustained severe brain damage and remained in what appeared to be a vegetative state for the rest of her life. In 1998, Schiavo’s husband wanted her feeding tube removed to allow her to die, as he believed that she would not have wanted to live in her current condition. Schiavo’s parents disagreed, and the family’s ensuing legal battle spanned seven years. In 2005, Schiavo’s feeding tubes were removed, and she passed away from dehydration 14 days later.

Technology reveals that brain structure and activity played an important role in Schiavo’s case. It can show the functions of different regions of the brain and identify neurological conditions in patients. Computerized tomography (CT), for example, produces images of narrow slices of the brain, functioning similar to X-rays but using an arc of radiation beams rather than a single ray. As CTs cannot indicate brain activity, electroencephalograms (EEGs) are used to measure electrical impulses on the surface of the brain. These impulses result from neurons communicating with one another, which require changes to the potential of a cell’s membrane, or its voltage.

This has many uses in the clinical setting, especially for patients in a vegetative state like Schiavo and patients with locked-in syndrome. When a patient is in a vegetative state, they are awake but unconscious of their surroundings and unable to perform cognitive activities. Only functions carried out by the brain stem, like maintaining a sleep-wake cycle, breathing, swallowing, and other basic activities, are performed. With locked-in syndrome, all voluntary muscles, except for those that control eye movement, are unable to function. Patients retain cognitive function and are aware of what goes on around them but cannot respond through speech and most movement. Patients with locked-in syndrome produce EEG readings identical to those of healthy patients, while EEG readings for vegetative state patients are flat, since there are no electrical impulses to be recorded on the surface of their brains.

CT scans and EEG readings played a critical role in the case of Schiavo. While Schiavo’s parents believed that their daughter was not in a vegetative state, most of the doctors who evaluated her disagreed. Dr. Ronald Cranford, who examined Schiavo during a 2002 trial, said in an interview that her EEG readings showed no activity on the surface of her brain and her CT scans revealed that many regions of her brain had wasted away. At her autopsy, Schiavo’s brain weighed less than half the weight of a healthy brain, confirming what the EEG and CT scans had indicated.

Schiavo’s case was highly publicized and ignited a heated debate about euthanasia, a process where someone, often those with terminal or debilitating medical conditions, is put to death painlessly. In Schiavo’s case, some believed that she would not have wanted to die. While EEGs and CT scans can generally reveal whether a patient is in a vegetative state or has locked-in syndrome, they cannot unveil activity deeper in the brain. Functional magnetic resonance imaging (fMRI), a more advanced technology, has been able to do this, providing another way to involve patients in their own life-and-death decisions. While the desires of vegetative state patients, like Schiavo, still cannot be recovered, this technology can benefit locked-in patients.

fMRIs display different levels of activity in slices of a brain through blood oxygen level dependent contrast. There is increased blood flow to active regions of the brain, because activated neurons need an increased oxygen supply. Nuclear magnetic resonance (NMR) spectroscopy is used to detect regions of the brain with oxygenated blood. fMRIs send radiofrequency magnetic pulses, disorienting hydrogen atoms and causing protons in the atoms to emit signals called H-NMR signals. Deoxygenated blood is magnetic and interferes with nearby H-NMR signals, causing deoxygenated regions of the brain to appear darker in fMRI scans while oxygenated regions of the brain appear brighter.

fMRI’s ability to measure activity throughout the whole brain rather than just the surface sometimes reveals brain activity in patients who do not respond to EEGs. This can correct the diagnoses of some patients from vegetative state to being locked-in. fMRIs can also be used to more accurately communicate with patients. Neuroscientist Adrian M. Owen significantly developed this area soon after Schiavo’s death, devising a yes-or-no questioning system that allowed patients to respond to his questions.

For most people, thinking about tennis activates the motor cortex of the brain, while thinking about navigating from room to room activates the spatial regions. Thus, doctors can ask their patients questions and ask them to think of playing tennis to respond “yes” or to think about walking from room to room to respond“no.” Responses to questions like “Are you in pain?” could then significantly improve the quality of care for these patients.

However, this capability also raises questions about euthanasia and whether doctors and researchers should have access to patients’ thoughts. Opponents of euthanasia, particularly disability activist groups, argue that severely disabled patients should not be presented with the choice to end their lives, especially because patients may feel that they are a burden to their families. Others, especially religious groups, believe that patients’ lives have value and should be preserved, regardless of their quality of life. Some also feel that being in a locked-in state is not painful and does not warrant euthanasia. However, those in favor of euthanasia believe that patients should have the choice to end their lives peacefully instead of artificially prolonging their suffering. Others also believe that death through euthanasia is more dignified to some patients than dying after years of life support.

Most locked-in patients only communicate through blinking or moving their eyes, using devices, or using sensors, many of which require some level of movement. fMRIs provide a more accurate way to communicate. However, because fMRI machines are large and can cost anywhere from a few hundred thousand dollars to over a million, they are less accessible than other methods of communication and thus have still not been widely employed in caring for locked-in patients.

Removing the uncertainty about patients’ desires in euthanasia decisions may push for the legalization of euthanasia in more scenarios. This could pressure some patients into consenting to death and contribute to ableist ideas that the lives of disabled people are not worth living. However, allowing more patients to choose when they want to die could help those who are unhappy living in a locked-in state. Regardless, as technologies like fMRIs continue to improve and become more accessible, doctors and researchers will better diagnose and treat locked-in patients, improving the quality of life for those who would otherwise be unable to communicate. As for vegetative state patients, having a living will prior to sustaining brain damage could help avoid cases like Schiavo’s.