Terminal lucidity, also known as paradoxical lucidity, rallying or the rally, is an unexpected return of mental clarity and memory, or suddenly regained consciousness that occurs in the time shortly before death in patients with severe

psychiatric Psychiatry is the medical specialty devoted to the diagnosis, prevention, and treatment of mental disorders. These include various maladaptations related to mood, behaviour, cognition, and perceptions. See glossary of psychiatry. Initial psy ...

neurological disorder A neurological disorder is any disorder of the nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weakn ...

s. This condition has been reported by physicians since the 19th century.

History

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 William MunkFRCP (1824 September 1816 – 20 December 1898) was an English physician, now remembered for his work as a medical historian and "Munk's Roll", a biographical reference work on the Royal College of Physicians. Life The eldest son ...

, for instance, in 1887 called the phenomenon "lucidity before death". According to historical reviews headed by the biologist Michael Nahm, who also has an interest in

mediumship Mediumship is the practice of purportedly mediating communication between familiar spirits or ghost, spirits of the dead and living human beings. Practitioners are known as "mediums" or "spirit mediums". There are different types of mediumship o ...

and

near-death experiences A near-death experience (NDE) is a profound personal experience associated with death or impending death which researchers claim share similar characteristics. When positive, such experiences may encompass a variety of sensations including detac ...

, the phenomena have been noted in patients with diseases which cause progressive cognitive impairment, such as

Alzheimer's disease Alzheimer's disease (AD) is a neurodegeneration, neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in short-term me ...

, but also

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdra ...

tumors A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

strokes A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop funct ...

meningitis Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, headache, and neck stiffness. Other symptoms include confusion or ...

, and

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

. However, terminal lucidity is not currently listed as a medical term. According to Nahm, it may be present even in cases of patients 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 Dementia is a disorder which manifests as a set of related symptoms, which usually surfaces when the brain is damaged by injury or disease. The symptoms involve progressive impairments in memory, thinking, and behavior, which negatively affec ...

such as Alzheimer's.

Causes

The earliest attempt at explanation was issued by

Benjamin Rush Benjamin Rush (April 19, 1813) was a Founding Fathers of the United States, Founding Father of the United States who signed the United States Declaration of Independence, and a civic leader in Philadelphia, where he was a physician, politician, ...

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. Johannes Friedreich, in 1839, proposed that the factors causing impairments may be reversed shortly before death, analogous to the reabsorption in terminal patients with

hydrocephalus Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased intracranial pressure, pressure inside the skull. Older people may have headaches, double vision, poor ...

, and that high fever may be a cause of it. According to Macleod (2009) in his observations, explanative causes could not be found for the variety of cases, but it was suggested that due to the modern pharmacology in terminal cases, the condition may be less common today. A recent proposed mechanism includes a non-tested hypothesis of

neuromodulation Neuromodulation is the physiological process by which a given neuron uses one or more chemicals to regulate diverse populations of neurons. Neuromodulators typically bind to metabotropic, G-protein coupled receptors (GPCRs) to initiate a second ...

, according to which near-death discharges of

neurotransmitters A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neur ...

and corticotropin-releasing peptides act upon preserved circuits of the

medial prefrontal cortex In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA46, ...

and

hippocampus The hippocampus (via Latin from Greek , 'seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, a ...

, promoting

memory retrieval Recall in memory refers to the mental process of retrieval of information from the past. Along with encoding and storage, it is one of the three core processes of memory. There are three main types of recall: free recall, cued recall and serial ...

and mental clarity.

References

{{Reflist Medical aspects of death Dementia Mental states 19th century in medicine 2009 neologisms