User:AnneZakh/Terminal lucidity

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Terminal lucidity, also known as rallying or the rally, or end-of-life experience. It is a poorly understood phenomenon in the medical and physiological research. It is is an unexpected return of mental clarity and memory, or suddenly regained consciousness that occurs in the time shortly before death in individuals with severe psychiatric or neurological disorders. This sudden clarity put individuals in good mood and allows them to say good-bye to their loved ones. This condition has been reported by physicians since the 19th century.

Sometimes terminal lucidity is also referred to as paradoxical lucidity, which is not accurate. In 2018, the U.S. National Institute on Aging defined paradoxical lucidity as an episode of meaningful and unexpected communication in people who are thought to have permanently lost the ability for communicative interaction because of the dementing process. By definition, paradoxical lucidity is independent of whether it happens before death or not. Terminal lucidity is a subset of paradoxical lucidity that happens around the time of death.

History[edit]
Several case reports in the 19th century described the unusual condition of an improvement and recovery of the mental state in patients days or weeks before death. William Munk, for instance, in 1887 called the phenomenon "lucidity before death". The research about terminal lucidity decreased in the 20th century

According to historical reviews headed by the biologist Michael Nahm, who also has an interest in mediumship and near-death experiences, the phenomena have been noted in people with diseases which cause progressive cognitive impairment, such as Alzheimer's disease, but also schizophrenia, tumors, strokes, meningitis, and Parkinson's disease.'''This makes terminal lucidity a phenomenon that is hard to understand. Till now, researchers do not know if it is the same process that happen to all people regardless of their medical history or if the phenomenon differ if people have different underlying disease.  Even more, in 2018, a group of researchers published a study they made where they observed people in a hospital. They found out that out of 151 deaths that happened in the general ward, only 6 people experienced terminal lucidity. . It is important to note that these 6 people had different admission causes and upon admission 3 of them were alert and aware and the other 3 were drowsy. The most common causes of death among these people were different infectious diseases or cancer- complications'''. However, terminal lucidity is not currently listed as a medical term.

According to Nahm, it may be present even in cases of people with previous mental disability. Nahm defines two subtypes: one that comes gradually (a week before death), and another that comes rapidly (hours before death), with the former occurring more often than the latter. There may be plenty of cases reported in literature, although the phrase terminal lucidity was coined in 2009. Interest in this condition, which dwindled during the 20th century, has been reignited by further studies. A 2020 research screened for what the authors preferred to call "paradoxical lucidity", a general term for unexpected remissions in dementias, independent of whether it followed a terminality process or not; it found strong association of the condition as a near-death phenomenon and stated that it can overlap the concept of "terminal lucidity" in some cases. Such a paradoxical condition is considered a challenge to the irreversibility paradigm of chronic degenerative dementias such as Alzheimer's.

Possible mechanisms[edit]
All proposed mechanisms must be considered as theoretical because there are no neuroscientific studies of terminal lucidity. However, near-death experiences, a related concept to terminal lucidity, can provide insight into possible mechanisms.

Near-death experiences have been reported across culture by people who unexpectedly recovered from life-threatening injury and by people who escaped from potentially fatal situation. People have been described their near-death experience as an "out-of-body experience", "sense of unity with nature", "apparent memory of a previous life", etc.. Near-death experiences are highly similar to terminal lucidity because they both occur just before death.

There is little research on the mechanism of near-death experiences because it is hard to determine who will experience them. Case reports have found that there is a sudden increase in electrical activity that is normally associated with consciousness in people who were dying due to critical illness. Even though this electrical abnormality could just be cell membrane losing activity because of lack of oxygen, it is possible that the surge of neurophysiological activity before death is related to the lucid episode before death.

The earliest attempt at explanation was issued by Benjamin Rush in 1812, which proposed the hypothesis that a reawakening could be due to a nervous excitation caused by pain or fever, or else because of dead blood vessels, released by a leakage of water in the brain chambers'''. '''

'''In 1826, Karl Friedrich Burdach, a physiologist and anatomist, focused on the anatomy of the brains of people who died and experienced this phenomena. He noted that there was changes in their brains, for example, there was blood outflow within the brain, presence of an unusual fluid filling the brain, increase in the size of the brain or softening in some parts of the brain. '''

'''In 1839, Johannes Friedreich, a physician, reviewed multiple case reports of people who experienced terminal lucidity and made a physiological explanation to it. He proposed that the factors causing impairments and brain dysfunctions may be reversed shortly before death. He reached this explanation from the idea that some studies showed that people who have water in their brains (hydrocephalus) will have less water before they die. '''

'''In 2009, Macleod made a great conclusion based on his observations, rather than other people's testimonies which the majority of the cases did use. Out of 100 deaths that happened in a hospice, 6 cases experienced terminal lucidity which lasted 12 hours and the patients died 48 hours later. Benzodiazepines, a medication to decrease arousal, were used on 3 patients and anti-emetics (medications to ease nausea and vomiting) but their doses did not exceed the maximum limit of doses recommended. Also, opioid was used in high dose in one of them. According to the observations, Macleod was not able to find any predictors or causes to terminal lucidity. However, Macleod concluded that terminal lucidity was common in the past more than today may be because we now have guidelines and recommendations for medication usage. For example, doctors in the past did not a limit for opioid use or had medications to ease nausea and vomiting.'''

'''In 2020, Mehmet Bostancikliglu figured out a new possible mechanism for terminal lucidity. In his research, he found out that around death time of people with dementia, their neurological signs (hyper-arousal and attention) significantly change. During this time, new brain transmitters are formed which are resistance to degeneration and this allows the unexpected cognition; terminal lucidity.'''

Further Discussion[edit]
Understanding the mechanism behind terminal lucidity has important ethical implications which can impact how researchers can move forward when formulating a study design.

'''Furthermore, terminal lucidity has a great influence on the families of the people who experience it. Terminal lucidity gives a false hope to the family members as they think that their loved ones are finally feeling better, however, death follows it. Some family members can ask the clinicians to change the care plan; hoping that this episode of consciousness come back. This also affects the clinicians as they try to help and comfort the family members but they are dealing with a not well understood phenomenon. '''