The Art of War

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https://en.wikipedia.org/wiki/The_Art_of_War

 

The Art of War

Author	Sun Tzu (traditional)
Country	China
Language	Classical Chinese
Subject	Military art
Publication date	5th century BC
Original text	The Art of War at Chinese Wikisource
Translation	The Art of War at Wikisource

The Art of War
Traditional Chinese	孫子兵法
Simplified Chinese	孙子兵法
Literal meaning	"Master Sun's Military Methods"

The Art of War (Chinese: 孫子兵法; lit. 'Sun Tzu's Military Method', pinyin: Sūnzǐ bīngfǎ) is an ancient Chinese military treatise dating from the Late Spring and Autumn Period (roughly 5th century BC). The work, which is attributed to the ancient Chinese military strategist Sun Tzu ("Master Sun"), is composed of 13 chapters. Each one is devoted to a different set of skills or art related to warfare and how it applies to military strategy and tactics. For almost 1,500 years it was the lead text in an anthology that was formalized as the Seven Military Classics by Emperor Shenzong of Song in 1080. The Art of War remains the most influential strategy text in East Asian warfare and has influenced both East Asian and Western military theory and thinking and has found a variety of applications in a myriad of competitive non-military endeavors across the modern world including espionage, culture, politics, business, and sports.

The book contains a detailed explanation and analysis of the 5th-century BC Chinese military, from weapons, environmental conditions, and strategy to rank and discipline. Sun also stressed the importance of intelligence operatives and espionage to the war effort. Considered one of history's finest military tacticians and analysts, his teachings and strategies formed the basis of advanced military training for millennia to come.

The book was translated into French and published in 1772 (re-published in 1782) by the French Jesuit Jean Joseph Marie Amiot. A partial translation into English was attempted by British officer Everard Ferguson Calthrop in 1905 under the title The Book of War. The first annotated English translation was completed and published by Lionel Giles in 1910. Military and political leaders such as the Chinese communist revolutionary Mao Zedong, Japanese daimyō Takeda Shingen, Vietnamese general Võ Nguyên Giáp, and American military generals Douglas MacArthur and Norman Schwarzkopf Jr. are all cited as having drawn inspiration from the book.

History

Text and commentaries

The Art of War is traditionally attributed to an ancient Chinese military general known as Sun Tzu (now Romanized "Sunzi") meaning "Master Sun". Sun Tzu was traditionally said to have lived in the 6th century BC, but The Art of War's earliest parts probably date to at least 100 years later.

Sima Qian's Records of the Grand Historian, the first of China's 24 dynastic histories, records an early Chinese tradition that a text on military matters was written by one "Sun Wu" (孫武) from the State of Qi, and that this text had been read and studied by King Helü of Wu (r. 514 BC – 495 BC). This text was traditionally identified with the received Master Sun's Art of War. The conventional view was that Sun Wu was a military theorist from the end of the Spring and Autumn period (776–471 BC) who fled his home state of Qi to the southeastern kingdom of Wu, where he is said to have impressed the king with his ability to quickly train even court women in military discipline and to have made Wu's armies powerful enough to challenge their western rivals in the state of Chu. This view is still widely held in China.

The strategist, poet, and warlord Cao Cao in the early 3rd century AD authored the earliest known commentary to the Art of War. Cao's preface makes clear that he edited the text and removed certain passages, but the extent of his changes were unclear historically. The Art of War appears throughout the bibliographical catalogs of the Chinese dynastic histories, but listings of its divisions and size varied widely.

Authorship

Fragments of The Art of War discovered as a part of the Yinqueshan Han Slips, showing the version of The Art of War that was popular in Han Dynasty (206 BC – 220 AD)

Beginning around the 12th century, some Chinese scholars began to doubt the historical existence of Sun Tzu, primarily on the grounds that he is not mentioned in the historical classic The Commentary of Zuo (Zuo Zhuan), which mentions most of the notable figures from the Spring and Autumn period. The name "Sun Wu" (孫武) does not appear in any text prior to the Records of the Grand Historian, and has been suspected to be a made-up descriptive cognomen meaning "the fugitive warrior", glossing the surname "Sun" as the related term "fugitive" (xùn 遜), while "Wu" is the ancient Chinese virtue of "martial, valiant" (wǔ 武), which corresponds to Sunzi's role as the hero's doppelgänger in the story of Wu Zixu. In the early 20th century, the Chinese writer and reformer Liang Qichao theorized that the text was actually written in the 4th century BC by Sun Tzu's purported descendant Sun Bin, as a number of historical sources mention a military treatise he wrote. Unlike Sun Wu, Sun Bin appears to have been an actual person who was a genuine authority on military matters, and may have been the inspiration for the creation of the historical figure "Sun Tzu" through a form of euhemerism.

In 1972, the Yinqueshan Han slips were discovered in two Han dynasty (206 BC – 220 AD) tombs near the city of Linyi in Shandong Province. Among the many bamboo slip writings contained in the tombs, which had been sealed between 134 and 118  BC, respectively were two separate texts, one attributed to "Sun Tzu", corresponding to the received text, and another attributed to Sun Bin, which explains and expands upon the earlier The Art of War by Sunzi. The Sun Bin text's material overlaps with much of the "Sun Tzu" text, and the two may be "a single, continuously developing intellectual tradition united under the Sun name". This discovery showed that much of the historical confusion was due to the fact that there were two texts that could have been referred to as "Master Sun's Art of War", not one. The content of the earlier text is about one-third of the chapters of the modern The Art of War, and their text matches very closely. It is now generally accepted that the earlier The Art of War was completed sometime between 500 and 430 BC.

Cultural influence

The beginning of The Art of War in a classical bamboo book from the reign of the Qianlong Emperor

Military and intelligence applications

Across East Asia, The Art of War was part of the syllabus for potential candidates of military service examinations.

During the Sengoku period (c. 1467–1568), the Japanese daimyō Takeda Shingen (1521–1573) is said to have become almost invincible in all battles without relying on guns, because he studied The Art of War. The book even gave him the inspiration for his famous battle standard "Fūrinkazan" (Wind, Forest, Fire and Mountain), meaning fast as the wind, silent as a forest, ferocious as fire and immovable as a mountain.

The translator Samuel B. Griffith offers a chapter on "Sun Tzu and Mao Tse-Tung" where The Art of War is cited as influencing Mao's On Guerrilla Warfare, On the Protracted War and Strategic Problems of China's Revolutionary War, and includes Mao's quote: "We must not belittle the saying in the book of Sun Wu Tzu, the great military expert of ancient China, 'Know your enemy and know yourself and you can fight a thousand battles without disaster.'"

During the Vietnam War, some Viet Cong officers extensively studied The Art of War and reportedly could recite entire passages from memory. General Võ Nguyên Giáp successfully implemented tactics described in The Art of War during the Battle of Dien Bien Phu ending major French involvement in Indochina and leading to the accords which partitioned Vietnam into North and South. General Giáp, later the main PVA military commander in the Vietnam War, was an avid student and practitioner of Sun Tzu's ideas.

Outside East Asia

The United States' defeat in the Vietnam War, more than any other event, brought Sun Tzu to the attention of leaders of U.S. military theory. The Department of the Army in the United States, through its Command and General Staff College, lists The Art of War as one example of a book that may be kept at a military unit's library. The Art of War is listed on the US Marine Corps Professional Reading Program (formerly known as the Commandant's Reading List). It is recommended reading for all United States Military Intelligence personnel. The Art of War is also used as instructional material at the US Military Academy at West Point, in the course Military Strategy (470), and it is also recommended reading for Officer cadets at the Royal Military Academy, Sandhurst. Some notable military leaders have stated the following about Sun Tzu and The Art of War:

"I always kept a copy of The Art of War on my desk." – General Douglas MacArthur, 5 Star General & Supreme Commander for the Allied Powers.

"I have read The Art of War by Sun Tzu. He continues to influence both soldiers & politicians." – General Colin Powell, Chairman of the Joint Chiefs of Staff, National Security Advisor, and Secretary of State.

According to some authors, the strategy of deception from The Art of War was studied and widely used by the KGB: "I will force the enemy to take our strength for weakness, and our weakness for strength, and thus will turn his strength into weakness".

Finnish Field Marshal Mannerheim and general Aksel Airo were avid readers of Art of War; Airo kept the book on his bedside table in his quarters.

Application outside the military

The Art of War has been applied to many fields outside of the military. Much of the text is about how to outsmart one's opponent without actually having to engage in physical battle. As such, it has found application as a training guide for many competitive endeavors that do not involve actual combat.

The Art of War is mentioned as an influence in the earliest known Chinese collection of stories about fraud (mostly in the realm of commerce), Zhang Yingyu's The Book of Swindles (Du pian xin shu, 杜騙新書, c. 1617), which dates to the late Ming dynasty.

Many business books have applied the lessons taken from the book to office politics and corporate business strategy. Many Japanese companies make the book required reading for their key executives. The book is also popular among Western business circles citing its utilitarian values regarding management practices. Many entrepreneurs and corporate executives have turned to it for inspiration and advice on how to succeed in competitive business situations. The book has also been applied to the field of education.

The Art of War has been the subject of legal books and legal articles on the trial process, including negotiation tactics and trial strategy.

The book The 48 Laws of Power by Robert Greene employs philosophies covered in The Art of War.

The Art of War has also been applied in sports. National Football League coach Bill Belichick, record holder of the most Super Bowl wins in history, has stated on multiple occasions his admiration for The Art of War. Brazilian association football coach Luiz Felipe Scolari actively used The Art of War for Brazil's successful 2002 World Cup campaign. During the tournament Scolari put passages of The Art of War underneath his players' doors at night.

The Art of War is often quoted while developing tactics and/or strategy in esports. "Play To Win" by David Sirlin analyses applications of the ideas from The Art of War in modern esports. The Art of War was released in 2014 as an e-book companion alongside the Art of War DLC for Europa Universalis IV, a PC strategy game by Paradox Development Studios, with a foreword by Thomas Johansson.

The Art of War has also been featured in the 2019 video game Age of Empires II: Definitive Edition from Microsoft.

Film and television

The Art of War and Sun Tzu have been referenced and quoted in many movies and television shows, including in the 1987 movie Wall Street, in which Gordon Gekko (Michael Douglas) frequently references it. The 20th James Bond film, Die Another Day (2002) also references The Art of War as the spiritual guide shared by Colonel Moon and his father. In The Sopranos, season 3, episode 8 ("He Is Risen"), Dr. Melfi suggests to Tony Soprano that he read the book.

In the Star Trek: The Next Generation first-season episode "The Last Outpost", first officer William Riker quotes The Art of War: "Fear is the true enemy, the only enemy". Captain Captain Picard expressed pleasure that Sun Tzu was still taught at Starfleet Academy. Later in the episode, a survivor from a long-dead nonhuman empire noted common aspects between his own people's wisdom and The Art of War with regard to knowing when and when not to fight.

The Art of War is a 2000 action spy film directed by Christian Duguay and starring Wesley Snipes, Michael Biehn, Anne Archer and Donald Sutherland.

Notable translations

Running Press miniature edition of the 1994 Ralph D. Sawyer translation, printed in 2003

• Sun Tzu on the Art of War. Translated by Lionel Giles. London: Luzac and Company. 1910.
• The Art of War. Translated by Samuel B. Griffith. Oxford: Oxford University Press. 1963. ISBN 978-0-19-501476-1. Part of the UNESCO Collection of Representative Works.
• Sun Tzu, The Art of War. Translated by Thomas Cleary. Boston: Shambhala Dragon Editions. 1988. ISBN 978-0877734529.
• The Art of Warfare. Translated by Roger Ames. Random House. 1993. ISBN 978-0-345-36239-1.
• The Art of War. Translated by John Minford. New York: Viking. 2002. ISBN 978-0-670-03156-6.
• The Art of War: Sunzi's Military Methods. Translated by Victor H. Mair. New York: Columbia University Press. 2007. ISBN 978-0-231-13382-1.
• The Art of War. Translated by Peter Harris. Everyman's Library. 2018. ISBN 978-1101908006.
• The Science of War: Sun Tzu's Art of War re-translated and re-considered. Translated by Christopher MacDonald. Hong Kong: Earnshaw Books. 2018. ISBN 978-988-8422-69-2.
• The Art of War. Translated by Michael Nylan. W.W. Norton & Company, Inc. 2020. ISBN 9781324004899.
• The Art of War. Translated by Thomas Huynh. Skylight Paths Publishing. 2008. ISBN 9781594732447.

Criticality accident

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Criticality_accident 

A criticality accident is an accidental uncontrolled nuclear fission chain reaction. It is sometimes referred to as a critical excursion, critical power excursion, or divergent chain reaction. Any such event involves the unintended accumulation or arrangement of a critical mass of fissile material, for example enriched uranium or plutonium. Criticality accidents can release potentially fatal radiation doses, if they occur in an unprotected environment.

Under normal circumstances, a critical or supercritical fission reaction (one that is self-sustaining in power or increasing in power) should only occur inside a safely shielded location, such as a reactor core or a suitable test environment. A criticality accident occurs if the same reaction is achieved unintentionally, for example in an unsafe environment or during reactor maintenance.

Though dangerous and frequently lethal to humans within the immediate area, the critical mass formed would not be capable of producing a massive nuclear explosion of the type that fission bombs are designed to produce. This is because all the design features needed to make a nuclear warhead cannot arise by chance. In some cases, the heat released by the chain reaction will cause the fissile (and other nearby) materials to expand. In such cases, the chain reaction can either settle into a low power steady state or may even become either temporarily or permanently shut down (subcritical).

In the history of atomic power development, at least 60 criticality accidents have occurred, including 22 in process environments, outside nuclear reactor cores or experimental assemblies, and 38 in small experimental reactors and other test assemblies. Although process accidents occurring outside reactors are characterized by large releases of radiation, the releases are localized. Nonetheless, fatal radiation exposures have occurred to persons close to these events, resulting in more than 20 fatalities. In a few reactor and critical experiment assembly accidents, the energy released has caused significant mechanical damage or steam explosions.

Physical basis

Criticality occurs when sufficient fissile material (a critical mass) accumulates in a small volume such that each fission, on average, produces a neutron that in turn strikes another fissile atom causing another fission; this causes the chain reaction to become self-sustaining within the mass of material. In other words, in a critical mass the number of neutrons emitted, over time, exactly equals the number of neutrons captured by another nucleus or lost to the environment. If the mass is supercritical, the number of neutrons emitted per unit time exceeds those absorbed or lost, resulting in a cascade of nuclear fissions at increasing rate.

Criticality can be achieved by using metallic uranium or plutonium, liquid solutions, or powder slurries. The chain reaction is influenced by range of parameters noted by the acronyms MAGIC MERV (for mass, absorption, geometry, interaction, concentration, moderation, enrichment, reflection, and volume) and MERMAIDS (for mass, enrichment, reflection, moderation, absorption, interaction, density, and shape). Temperature is also a factor.

Calculations can be performed to determine the conditions needed for a critical state, mass, geometry, concentration etc. Where fissile materials are handled in civil and military installations, specially trained personnel are employed to carry out such calculations, and to ensure that all reasonably practicable measures are used to prevent criticality accidents, during both planned normal operations and any potential process upset conditions that cannot be dismissed on the basis of negligible likelihoods (reasonably foreseeable accidents).

The assembly of a critical mass establishes a nuclear chain reaction, resulting in an exponential rate of change in the neutron population over space and time leading to an increase in neutron flux. This increased flux and attendant fission rate produces radiation that contains both a neutron and gamma ray component and is extremely dangerous to any unprotected nearby life-form. The rate of change of neutron population depends on the neutron generation time, which is characteristic of the neutron population, the state of "criticality", and the fissile medium.

A nuclear fission creates approximately 2.5 neutrons per fission event on average. Hence, to maintain a stable, exactly critical chain reaction, 1.5 neutrons per fission event must either leak from the system or be absorbed without causing further fissions.

For every 1,000 neutrons released by fission, a small number, typically no more than about 7, are delayed neutrons which are emitted from the fission product precursors, called delayed neutron emitters. This delayed neutron fraction, on the order of 0.007 for uranium, is crucial for the control of the neutron chain reaction in reactors. It is called one dollar of reactivity. The lifetime of delayed neutrons ranges from fractions of seconds to almost 100 seconds after fission. The neutrons are usually classified in 6 delayed neutron groups. The average neutron lifetime considering delayed neutrons is approximately 0.1 sec, which makes the chain reaction relatively easy to control over time. The remaining 993 prompt neutrons are released very quickly, approximately 1 μs after the fission event.

In steady-state operation, nuclear reactors operate at exact criticality. When at least one dollar of reactivity is added above the exact critical point (where the neutron production rate balances the rate of neutron losses, from both absorption and leakage) then the chain reaction does not rely on delayed neutrons. In such cases, the neutron population can rapidly increase exponentially, with a very small time constant, known as the prompt neutron lifetime. Thus there is a very large increase in neutron population over a very short time frame. Since each fission event contributes approximately 200 MeV per fission, this results in a very large energy burst as a "prompt-critical spike". This spike can be easily detected by radiation dosimetry instrumentation and "criticality accident alarm system" detectors that are properly deployed.

Accident types

Criticality accidents are divided into one of two categories:

• Process accidents, where controls in place to prevent any criticality are breached;
• Reactor accidents, which occur due to operator errors or other unintended events (e.g., during maintenance or fuel loading) in locations intended to achieve or approach criticality, such as nuclear power plants, nuclear reactors, and nuclear experiments.

Excursion types can be classified into four categories depicting the nature of the evolution over time:

1. Prompt criticality excursion
2. Transient criticality excursion
3. Exponential excursion
4. Steady-state excursion

The prompt-critical excursion is characterized by a power history with an initial prompt-critical spike as previously noted, which either self-terminates or continues with a tail region that decreases over an extended period of time. The transient critical excursion is characterized by a continuing or repeating spike pattern (sometimes known as "chugging") after the initial prompt-critical excursion. The longest of the 22 process accidents occurred at Hanford Works in 1962 and lasted for 37.5 hours. The 1999 Tokaimura nuclear accident remained critical for about 20 hours, until it was shut down by active intervention. The exponential excursion is characterized by a reactivity of less than one dollar added, where the neutron population rises as an exponential over time, until either feedback effects or intervention reduce the reactivity. The exponential excursion can reach a peak power level, then decrease over time, or reach a steady-state power level, where the critical state is exactly achieved for a "steady-state" excursion.

The steady-state excursion is also a state which the heat generated by fission is balanced by the heat losses to the ambient environment. This excursion has been characterized by the Oklo natural reactor that was naturally produced within uranium deposits in Gabon, Africa about 1.7 billion years ago.

Known incidents

A Los Alamos report (McLaughlin et al) recorded 60 criticality accidents between 1945 and 1999. These caused 21 deaths: seven in the United States, ten in the Soviet Union, two in Japan, one in Argentina, and one in Yugoslavia. Nine have been due to process accidents, and the others from research reactor accidents.

Criticality accidents have occurred in the context of production and testing of fissile material for both nuclear weapons and nuclear reactors.

• 

  The sphere of plutonium surrounded by neutron-reflecting tungsten carbide blocks in a re-enactment of Harry Daghlian's 1945 experiment.

• 

  A re-creation of the Slotin incident. The inside hemisphere with the thumb-hole next to the hand is beryllium (replacing the uranium tamper in a Fat Man bomb), with an external larger metal sphere under it, of aluminium. The 3.5-inch-diameter (89 mm) plutonium "demon core" (the same as in the Daghlian incident) was inside at the time of the accident, and would not be visible. However, its dimensions are comparable with the two small half-spheres shown resting nearby.

• 

  Image of the Lady Godiva assembly in the scrammed (safe) configuration.

• 

  Image of the Lady Godiva assembly, showing the damage caused to the supporting rods after the excursion of February 1954. Note the images are of different assemblies.

There was speculation although not confirmed within criticality accident experts, that Fukushima 3 suffered a criticality accident. Based on incomplete information about the 2011 Fukushima I nuclear accidents, Dr. Ferenc Dalnoki-Veress speculates that transient criticalities may have occurred there. Noting that limited, uncontrolled chain reactions might occur at Fukushima I, a spokesman for the International Atomic Energy Agency (IAEA) "emphasized that the nuclear reactors won't explode." By 23 March 2011, neutron beams had already been observed 13 times at the crippled Fukushima nuclear power plant. While a criticality accident was not believed to account for these beams, the beams could indicate nuclear fission is occurring. On 15 April, TEPCO reported that nuclear fuel had melted and fallen to the lower containment sections of three of the Fukushima I reactors, including reactor three. The melted material was not expected to breach one of the lower containers, which could cause a massive radioactivity release. Instead, the melted fuel is thought to have dispersed uniformly across the lower portions of the containers of reactors No. 1, No. 2 and No. 3, making the resumption of the fission process, known as a "recriticality", most unlikely.

Observed effects

Image of a 60-inch cyclotron, circa 1939, showing an external beam of accelerated ions (perhaps protons or deuterons) ionizing the surrounding air and causing an ionized-air glow. Due to the similar mechanism of production, the blue glow is thought to resemble the "blue flash" seen by Harry Daghlian and other witnesses of criticality accidents.

Blue glow

See also: Ionized-air glow

It has been observed that many criticality accidents emit a blue flash of light.

The blue glow of a criticality accident results from the fluorescence of the excited ions, atoms and molecules of the surrounding medium falling back to unexcited states. This is also the reason electrical sparks in air, including lightning, appear electric blue. The smell of ozone was said to be a sign of high ambient radioactivity by Chernobyl liquidators.

This blue flash or "blue glow" can also be attributed to Cherenkov radiation, if either water is involved in the critical system or when the blue flash is experienced by the human eye. Additionally, if ionizing radiation directly transects the vitreous humor of the eye, Cherenkov radiation can be generated and perceived as a visual blue glow/spark sensation.

It is a coincidence that the color of Cherenkov light and light emitted by ionized air are a very similar blue; their methods of production are different. Cherenkov radiation does occur in air for high-energy particles (such as particle showers from cosmic rays) but not for the lower energy charged particles emitted from nuclear decay.

Heat effects

Some people reported feeling a "heat wave" during a criticality event. It is not known whether this may be a psychosomatic reaction to the realization of what has just occurred (i.e. the high probability of inevitable impending death from a fatal radiation dose), or if it is a physical effect of heating (or non-thermal stimulation of heat sensing nerves in the skin) due to radiation emitted by the criticality event.

A review of all of the criticality accidents with eyewitness accounts indicates that the heat waves were only observed when the fluorescent blue glow (the non-Cherenkov light, see above) was also observed. This would suggest a possible relationship between the two, and indeed, one can be potentially identified. In dense air, over 30% of the emission lines from nitrogen and oxygen are in the ultraviolet range, and about 45% are in the infrared range. Only about 25% are in the visible range. Since the skin feels light (visible or otherwise) through its heating of the skin surface, it is possible that this phenomenon can explain the heat wave perceptions. However, this explanation has not been confirmed and may be inconsistent with the intensity of light reported by witnesses compared to the intensity of heat perceived. Further research is hindered by the small amount of data available from the few instances where humans have witnessed these incidents and survived long enough to provide a detailed account of their experiences and observations.

Approximate number system

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Approximate_number_system 

The approximate number system (ANS) is a cognitive system that supports the estimation of the magnitude of a group without relying on language or symbols. The ANS is credited with the non-symbolic representation of all numbers greater than four, with lesser values being carried out by the parallel individuation system, or object tracking system. Beginning in early infancy, the ANS allows an individual to detect differences in magnitude between groups. The precision of the ANS improves throughout childhood development and reaches a final adult level of approximately 15% accuracy, meaning an adult could distinguish 100 items versus 115 items without counting. The ANS plays a crucial role in development of other numerical abilities, such as the concept of exact number and simple arithmetic. The precision level of a child's ANS has been shown to predict subsequent mathematical achievement in school. The ANS has been linked to the intraparietal sulcus of the brain.

History

Piaget's theory

Jean Piaget was a Swiss developmental psychologist who devoted much of his life to studying how children learn. A book summarizing his theories on number cognition, The Child's Conception of Number, was published in 1952. Piaget's work supported the viewpoint that children do not have a stable representation of number until the age of six or seven. His theories indicate that mathematical knowledge is slowly gained and during infancy any concept of sets, objects, or calculation is absent.

Challenging the Piagetian viewpoint

Piaget's ideas pertaining to the absence of mathematical cognition at birth have been steadily challenged. The work of Rochel Gelman and C. Randy Gallistel among others in the 1970s suggested that preschoolers have intuitive understanding of the quantity of a set and its conservation under non cardinality-related changes, expressing surprise when objects disappear without an apparent cause.

Current theory

Beginning as infants, people have an innate sense of approximate number that depends on the ratio between sets of objects. Throughout life the ANS becomes more developed, and people are able to distinguish between groups having smaller differences in magnitude. The ratio of distinction is defined by Weber's law, which relates the different intensities of a sensory stimulus that is being evaluated. In the case of the ANS, as the ratio between the magnitudes increases, the ability to discriminate between the two quantities increases.

Today, some theorize that the ANS lays the foundation for higher-level arithmetical concepts. Research has shown that the same areas of the brain are active during non-symbolic number tasks in infants and both non-symbolic and more sophisticated symbolic number tasks in adults. These results could suggest that the ANS contributes over time to the development of higher-level numerical skills that activate the same part of the brain.

However, longitudinal studies do not necessarily find that non-symbolic abilities predict later symbolic abilities. Conversely, early symbolic number abilities have been found to predict later non-symbolic abilities, not vice versa as predicted. In adults for example, non-symbolic number abilities do not always explain mathematics achievement.

Neurological basis

Brain imaging studies have identified the parietal lobe as being a key brain region for numerical cognition. Specifically within this lobe is the intraparietal sulcus which is "active whenever we think about a number, whether spoken or written, as a word or as an Arabic digit, or even when we inspect a set of objects and think about its cardinality". When comparing groups of objects, activation of the intraparietal sulcus is greater when the difference between groups is numerical rather than an alternative factor, such as differences in shape or size. This indicates that the intraparietal sulcus plays an active role when the ANS is employed to approximate magnitude.

Parietal lobe brain activity seen in adults is also observed during infancy during non-verbal numerical tasks, suggesting that the ANS is present very early in life. A neuroimaging technique, functional Near-Infrared Spectroscopy, was performed on infants revealing that the parietal lobe is specialized for number representation before the development of language. This indicates that numerical cognition may be initially reserved to the right hemisphere of the brain and becomes bilateral through experience and the development of complex number representation.

It has been shown that the intraparietal sulcus is activated independently of the type of task being performed with the number. The intensity of activation is dependent on the difficulty of the task, with the intraparietal sulcus showing more intense activation when the task is more difficult. In addition, studies in monkeys have shown that individual neurons can fire preferentially to certain numbers over others. For example, a neuron could fire at maximum level every time a group of four objects is seen, but will fire less to a group three or five objects.

Pathology

Damage to intraparietal sulcus

Damage done to parietal lobe, specifically in the left hemisphere, can produce difficulties in counting and other simple arithmetic. Damage directly to the intraparietal sulcus has been shown to cause acalculia, a severe disorder in mathematical cognition. Symptoms vary based the location of damage, but can include the inability to perform simple calculations or to decide that one number is larger than another. Gerstmann syndrome, a disease resulting in lesions in the left parietal and temporal lobes, results in acalculia symptoms and further confirms the importance of the parietal region in the ANS.

Developmental delays

A syndrome known as dyscalculia is seen in individuals who have unexpected difficulty understanding numbers and arithmetic despite adequate education and social environments.^[13] This syndrome can manifest in several different ways from the inability to assign a quantity to Arabic numerals to difficulty with times tables. Dyscalculia can result in children falling significantly behind in school, regardless of having normal intelligence levels.

In some instances, such as Turner syndrome, the onset of dyscalculia is genetic. Morphological studies have revealed abnormal lengths and depths of the right intraparietal sulcus in individuals suffering from Turner syndrome. Brain imaging in children exhibiting symptoms of dyscalculia show less gray matter or less activation in the intraparietal regions stimulated normally during mathematical tasks. Additionally, impaired ANS acuity has been shown to differentiate children with dyscalculia from their normally-developing peers with low maths achievement.

Further research and theories

Impact of the visual cortex

The intraparietal region relies on several other brain systems to accurately perceive numbers. When using the ANS we must view the sets of objects in order to evaluate their magnitude. The primary visual cortex is responsible for disregarding irrelevant information, such as the size or shape of the objects. Certain visual cues can sometimes affect how the ANS functions.

Arranging the items differently can alter the effectiveness of the ANS. One arrangement proven to influence the ANS is visual nesting, or placing the objects within one another. This configuration affects the ability to distinguish each item and add them together at the same time. The difficulty results in underestimation of the magnitude present in the set or a longer amount of time needed to perform an estimate.

Another visual representation that affects the ANS is the spatial-numerical association response code, or the SNARC effect. The SNARC effect details the tendency of larger numbers to be responded to faster by the right hand and lower numbers by the left hand, suggesting that the magnitude of a number is linked to a spatial representation. Dehaene and other researchers believe this effect is caused by the presence of a “mental number line” in which small numbers appear on the left and increase as you move right. The SNARC effect indicates that the ANS works more effectively and accurately if the larger set of objects is on the right and the smaller on the left.

Development and mathematical performance

Although the ANS is present in infancy before any numerical education, research has shown a link between people's mathematical abilities and the accuracy in which they approximate the magnitude of a set. This correlation is supported by several studies in which school-aged children's ANS abilities are compared to their mathematical achievements. At this point the children have received training in other mathematical concepts, such as exact number and arithmetic. More surprisingly, ANS precision before any formal education accurately predicts better math performance. A study involving 3- to 5-year-old children revealed that ANS acuity corresponds to better mathematical cognition while remaining independent of factors that may interfere, such as reading ability and the use of Arabic numerals.

ANS in animals

Main article: Number sense in animals

Many species of animals exhibit the ability to assess and compare magnitude. This skill is believed to be a product of the ANS. Research has revealed this capability in both vertebrate and non-vertebrate animals including birds, mammals, fish, and even insects. In primates, implications of the ANS have been steadily observed through research. One study involving lemurs showed that they were able to distinguish groups of objects based only on numerical differences, suggesting that humans and other primates utilize a similar numerical processing mechanism.

In a study comparing students to guppies, both the fish and students performed the numerical task almost identically. The ability for the test groups to distinguish large numbers was dependent on the ratio between them, suggesting the ANS was involved. Such results seen when testing guppies indicate that the ANS may have been evolutionarily passed down through many species.

Applications in society

Implications for the classroom

Understanding how the ANS affects students' learning could be beneficial for teachers and parents. The following tactics have been suggested by neuroscientists to utilize the ANS in school:

• Counting or abacus games
• Simple board games
• Computer-based number association games
• Teacher sensitivity and different teaching methods for different learners

Such tools are most helpful in training the number system when the child is at an earlier age. Children coming from a disadvantaged background with risk of arithmetic problems are especially impressionable by these tactics.

Numeracy

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Numeracy 

Children in Laos have fun as they improve numeracy with "Number Bingo". They roll three dice, construct an equation from the numbers to produce a new number, then cover that number on the board, trying to get four in a row.

 

Number bingo improves math skills. LPB Laos.

Numeracy is the ability to understand, reason with, and to apply simple numerical concepts. The charity National Numeracy states: "Numeracy means understanding how mathematics is used in the real world and being able to apply it to make the best possible decisions...It’s as much about thinking and reasoning as about 'doing sums'". Basic numeracy skills consist of comprehending fundamental arithmetical operations like addition, subtraction, multiplication, and division. For example, if one can understand simple mathematical equations such as 2 + 2 = 4, then one would be considered to possess at least basic numeric knowledge. Substantial aspects of numeracy also include number sense, operation sense, computation, measurement, geometry, probability and statistics. A numerically literate person can manage and respond to the mathematical demands of life.

By contrast, innumeracy (the lack of numeracy) can have a negative impact. Numeracy has an influence on healthy behaviors, financial literacy, and career decisions. Therefore, innumeracy may negatively affect economic choices, financial outcomes, health outcomes, and life satisfaction. It also may distort risk perception in health decisions. Greater numeracy has been associated with reduced susceptibility to framing effects, less influence of nonnumerical information such as mood states, and greater sensitivity to different levels of numerical risk. Ellen Peters and her colleagues argue that achieving the benefits of numeric literacy, however, may depend on one's numeric self-efficacy or confidence in one's skills.

Representation of numbers

Humans have evolved to mentally represent numbers in two major ways from observation (not formal math). These representations are often thought to be innate (see Numerical cognition), to be shared across human cultures, to be common to multiple species, and not to be the result of individual learning or cultural transmission. They are:

1. Approximate representation of numerical magnitude, and
2. Precise representation of the quantity of individual items.

Approximate representations of numerical magnitude imply that one can relatively estimate and comprehend an amount if the number is large (see Approximate number system). For example, one experiment showed children and adults arrays of many dots. After briefly observing them, both groups could accurately estimate the approximate number of dots. However, distinguishing differences between large numbers of dots proved to be more challenging.

Precise representations of distinct items demonstrate that people are more accurate in estimating amounts and distinguishing differences when the numbers are relatively small (see Subitizing). For example, in one experiment, an experimenter presented an infant with two piles of crackers, one with two crackers the other with three. The experimenter then covered each pile with a cup. When allowed to choose a cup, the infant always chose the cup with more crackers because the infant could distinguish the difference.

Both systems—approximate representation of magnitude and precise representation quantity of individual items—have limited power. For example, neither allows representations of fractions or negative numbers. More complex representations require education. However, achievement in school mathematics correlates with an individual's unlearned approximate number sense.

Definitions and assessment

Fundamental (or rudimentary) numeracy skills include understanding of the real number line, time, measurement, and estimation. Fundamental skills include basic skills (the ability to identify and understand numbers) and computational skills (the ability to perform simple arithmetical operations and compare numerical magnitudes).

More sophisticated numeracy skills include understanding of ratio concepts (notably fractions, proportions, percentages, and probabilities), and knowing when and how to perform multistep operations. Two categories of skills are included at the higher levels: the analytical skills (the ability to understand numerical information, such as required to interpret graphs and charts) and the statistical skills (the ability to apply higher probabilistic and statistical computation, such as conditional probabilities).

A variety of tests have been developed for assessing numeracy and health numeracy. Different tests have been developed to evaluate health numeracy. Two of these tests that have been found to be “reliable and valid” are the GHNT-21 and GHNT-6.

Childhood influences

The first couple of years of childhood are considered to be a vital part of life for the development of numeracy and literacy. There are many components that play key roles in the development of numeracy at a young age, such as Socioeconomic Status (SES), parenting, Home Learning Environment (HLE), and age.

Socioeconomic status

Children who are brought up in families with high SES tend to be more engaged in developmentally enhancing activities. These children are more likely to develop the necessary abilities to learn and to become more motivated to learn. More specifically, a mother's education level is considered to have an effect on the child's ability to achieve in numeracy. That is, mothers with a high level of education will tend to have children who succeed more in numeracy.

A number of studies have, moreover, proved that the education level of the mother is strongly correlated with the average age of getting married. More precisely, females who entered the marriage later, tend to have greater autonomy, chances for skills premium and level of education (i.e. numeracy). Hence, they were more likely to share this experience with children.

Parenting

Parents are advised to collaborate with their child in simple learning exercises, such as reading a book, painting, drawing, and playing with numbers. On a more expressive note, the act of using complex language, being more responsive towards the child, and establishing warm interactions are recommended to parents with the confirmation of positive numeracy outcomes. When discussing beneficial parenting behaviors, a feedback loop is formed because pleased parents are more willing to interact with their child, which in essence promotes better development in the child.

Home-learning environment

Along with parenting and SES, a strong home-learning environment increases the likelihood of the child being prepared for comprehending complex mathematical schooling. For example, if a child is influenced by many learning activities in the household, such as puzzles, coloring books, mazes, or books with picture riddles, then they will be more prepared to face school activities.

Age

Age is accounted for when discussing the development of numeracy in children. Children under the age of 5 have the best opportunity to absorb basic numeracy skills. After the age of seven, achievement of basic numeracy skills become less influential. For example, a study was conducted to compare the reading and mathematical abilities between children of ages five and seven, each in three different mental capacity groups (underachieving, average, and overachieving). The differences in the amount of knowledge retained were greater between the three different groups aged five than between the groups aged seven. This reveals that those of younger ages have an opportunity to retain more information, like numeracy. According to Gelman and Gallistel in The Child’s Understanding of Number, ‘children as young as 2 years can accurately judge numerosity provided that the numerosity is not larger than two or three’. Children as young as three have been found to understand elementary mathematical concepts. Kilpatrick and his colleagues state ‘most preschoolers show that they can understand and perform simple addition and subtraction by at least 3 years of age’. Lastly, it has been observed that pre-school children benefit from their basic understanding of ‘counting, reading and writing of numbers, understanding of simple addition and subtraction, numerical reasoning, classifying of objects and shapes, estimating, measuring, [and the] reproduction of number patterns’.

Literacy

There seems to be a relationship between literacy and numeracy, which can be seen in young children. Depending on the level of literacy or numeracy at a young age, one can predict the growth of literacy and/ or numeracy skills in future development. There is some evidence that humans may have an inborn sense of number. In one study for example, five-month-old infants were shown two dolls, which were then hidden with a screen. The babies saw the experimenter pull one doll from behind the screen. Without the child's knowledge, a second experimenter could remove, or add dolls, unseen behind the screen. When the screen was removed, the infants showed more surprise at an unexpected number (for example, if there were still two dolls). Some researchers have concluded that the babies were able to count, although others doubt this and claim the infants noticed surface area rather than number.

Employment

Numeracy has a huge impact on employment. In a work environment, numeracy can be a controlling factor affecting career achievements and failures. Many professions require individuals to have well-developed numerical skills: for example, mathematician, physicist, accountant, actuary, Risk Analyst, financial analyst, engineer, and architect. This is why a major target of the Sustainable Development Goal 4 is to substantially increase the number of youths who have relevant skills for decent work and employment because, even outside these specialized areas, the lack of numeracy skills can reduce employment opportunities and promotions, resulting in unskilled manual careers, low-paying jobs, and even unemployment. For example, carpenters and interior designers need to be able to measure, use fractions, and handle budgets. Another example of numeracy influencing employment was demonstrated at the Poynter Institute. The Poynter Institute has recently included numeracy as one of the skills required by competent journalists. Max Frankel, former executive editor of The New York Times, argues that "deploying numbers skillfully is as important to communication as deploying verbs". Unfortunately, it is evident that journalists often show poor numeracy skills. In a study by the Society of Professional Journalists, 58% of job applicants interviewed by broadcast news directors lacked an adequate understanding of statistical materials.

To assess job applicants, psychometric numerical reasoning tests have been created by occupational psychologists, who are involved in the study of numeracy. These tests are used to assess ability to comprehend and apply numbers. They are sometimes administered with a time limit, so that the test-taker must think quickly and concisely. Research has shown that these tests are very useful in evaluating potential applicants because they do not allow the applicants to prepare for the test, unlike interview questions. This suggests that an applicant's results are reliable and accurate.

These tests first became prevalent during the 1980s, following the pioneering work of psychologists, such as P. Kline, who published a book in 1986 entitled A handbook of test construction: Introduction to psychometric design, which explained that psychometric testing could provide reliable and objective results, which could be used to assess a candidate's numerical abilities.

Innumeracy and dyscalculia

The term innumeracy is a neologism, coined by analogy with illiteracy. Innumeracy refers to a lack of ability to reason with numbers. The term was coined by cognitive scientist Douglas Hofstadter; however, it was popularized in 1989 by mathematician John Allen Paulos in his book Innumeracy: Mathematical Illiteracy and its Consequences.

Developmental dyscalculia refers to a persistent and specific impairment of basic numerical-arithmetical skills learning in the context of normal intelligence.

Patterns and differences

The root causes of innumeracy vary. Innumeracy has been seen in those suffering from poor education and childhood deprivation of numeracy. Innumeracy is apparent in children during the transition between numerical skills obtained before schooling and the new skills taught in the education departments because of their memory capacity to comprehend the material. Patterns of innumeracy have also been observed depending on age, gender, and race. Older adults have been associated with lower numeracy skills than younger adults. Men have been identified to have higher numeracy skills than women. Some studies seem to indicate young people of African heritage tend to have lower numeracy skills. The Trends in International Mathematics and Science Study (TIMSS) in which children at fourth-grade (average 10 to 11 years) and eighth-grade (average 14 to 15 years) from 49 countries were tested on mathematical comprehension. The assessment included tests for number, algebra (also called patterns and relationships at fourth grade), measurement, geometry, and data. The latest study, in 2003, found that children from Singapore at both grade levels had the highest performance. Countries like Hong Kong SAR, Japan, and Taiwan also shared high levels of numeracy. The lowest scores were found in countries like South Africa, Ghana, and Saudi Arabia. Another finding showed a noticeable difference between boys and girls, with some exceptions. For example, girls performed significantly better in Singapore, and boys performed significantly better in the United States.

Theory

There is a theory that innumeracy is more common than illiteracy when dividing cognitive abilities into two separate categories. David C. Geary, a notable cognitive developmental and evolutionary psychologist from the University of Missouri, created the terms "biological primary abilities" and "biological secondary abilities". Biological primary abilities evolve over time and are necessary for survival. Such abilities include speaking a common language or knowledge of simple mathematics. Biological secondary abilities are attained through personal experiences and cultural customs, such as reading or high level mathematics learned through schooling. Literacy and numeracy are similar in the sense that they are both important skills used in life. However, they differ in the sorts of mental demands each makes. Literacy consists of acquiring vocabulary and grammatical sophistication, which seem to be more closely related to memorization, whereas numeracy involves manipulating concepts, such as in calculus or geometry, and builds from basic numeracy skills. This could be a potential explanation of the challenge of being numerate.

Innumeracy and risk perception in health decision-making

Health numeracy has been defined as "the degree to which individuals have the capacity to access, process, interpret, communicate, and act on numerical, quantitative, graphical, biostatistical, and probabilistic health information needed to make effective health decisions". The concept of health numeracy is a component of the concept of health literacy. Health numeracy and health literacy can be thought of as the combination of skills needed for understanding risk and making good choices in health-related behavior.

Health numeracy requires basic numeracy but also more advanced analytical and statistical skills. For instance, health numeracy also requires the ability to understand probabilities or relative frequencies in various numerical and graphical formats, and to engage in Bayesian inference, while avoiding errors sometimes associated with Bayesian reasoning (see Base rate fallacy, Conservatism (Bayesian)). Health numeracy also requires understanding terms with definitions that are specific to the medical context. For instance, although 'survival' and 'mortality' are complementary in common usage, these terms are not complementary in medicine (see five-year survival rate). Innumeracy is also a very common problem when dealing with risk perception in health-related behavior; it is associated with patients, physicians, journalists and policymakers. Those who lack or have limited health numeracy skills run the risk of making poor health-related decisions because of an inaccurate perception of information. For example, if a patient has been diagnosed with breast cancer, being innumerate may hinder her ability to comprehend her physician's recommendations, or even the severity of the health concern or even the likelihood of treatment benefits. One study found that people tended to overestimate their chances of survival or even to choose lower-quality hospitals. Innumeracy also makes it difficult or impossible for some patients to read medical graphs correctly. Some authors have distinguished graph literacy from numeracy. Indeed, many doctors exhibit innumeracy when attempting to explain a graph or statistics to a patient. A misunderstanding between a doctor and patient, due to either the doctor, patient, or both being unable to comprehend numbers effectively, could result in serious harm to health.

Different presentation formats of numerical information, for instance natural frequency icon arrays, have been evaluated to assist both low-numeracy and high-numeracy individuals. Other data formats provide more assistance to low-numeracy people.

Evolution of numeracy

In the field of economic history, numeracy is often used to assess human capital at times when there was no data on schooling or other educational measures. Using a method called age-heaping, researchers like Professor Jörg Baten study the development and inequalities of numeracy over time and throughout regions. For example, Baten and Hippe find a numeracy gap between regions in western and central Europe and the rest of Europe for the period 1790–1880. At the same time, their data analysis reveals that these differences as well as within country inequality decreased over time. Taking a similar approach, Baten and Fourie find overall high levels of numeracy for people in the Cape Colony (late 17th to early 19th century).

In contrast to these studies comparing numeracy over countries or regions, it is also possible to analyze numeracy within countries. For example, Baten, Crayen and Voth look at the effects of war on numeracy in England, and Baten and Priwitzer find a "military bias" in what is today western Hungary: people opting for a military career had - on average - better numeracy indicators (1 BCE to 3CE).

Psychic numbing

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Psychic_numbing 

Psychic numbing is a tendency for individuals or societies to withdraw attention from past experiences that were traumatic, or from future threats that are perceived to have massive consequences but low probability. Psychic numbing can be a response to threats as diverse as financial and economic collapse, the risk of nuclear weapon detonations, pandemics, and global warming. It is also important to consider the neuroscience behind the phenomenon, which gives validation to the observable human behavior. The term has evolved to include both societies as well as individuals, so psychic numbing can be viewed from either a collectivist or an individualist standpoint. Individualist psychic numbing is found in rape survivors and people who have post-traumatic stress disorder.

History

The original concept of psychic numbing argued by Robert Jay Lifton was that it manifests itself collectively. This means that a society or a culture adapts this withdrawn attention outlook and collectively applies it to current issues.

Robert Jay Lifton: "Beyond Psychic Numbing: A Call to Awareness"

Lifton's 4 Focal Points:

1. Hiroshima as a text for "psychic numbing"
2. Nuclear Illusions
3. What are nuclear weapons doing to us? (Nuclear fundamentalism)
4. Hope for the future

Lifton's main area of focus was the Hiroshima bombing during World War II. He broke up his analysis of the bombing into psychological stages that spread at the societal level. Lifton's article, "Beyond Psychic Numbing: A Call to Awareness", addressed a concern that was new at the time: nuclear warfare. He argued now that there is a single weapon in the world that can cause so much damage, humans need to be more alert and confront the images of nuclear power and an ever increasing nuclear actuality. There is a societal understanding now that countries can create nuclear weapons; this led to Lifton's coining of the term "nuclear fundamentalism".

All these are argued by Lifton to be beneficial at times, however rather inadequate for helping people feel better about the ubiquity of nuclear weapons and potential warfare. There needs to be a sense of control in order to comprehend the consequences of nuclear warfare as well as strategies to combat the psychological grip it has on individuals.

Lifton's final argument regarding hope for the future is that society must take action. He uses Vietnam veterans as a reference point. He has worked with them before and noticed partial changes, while he agrees this is good, society must adapt an awareness that aims to teach and educate as opposed to avoid and withdraw from the potential threats to survival.

Neuroscience

Psychic numbing has been associated with post-traumatic stress disorder (PTSD) because they share the same attributes of withdrawal and behavioral changes when presented with a stimuli that triggers a reminder of the traumatic event or with a very intense neutral stimuli. The observable emotional response is not enough to understand the concept of psychic numbing. Therefore, neuroscience and the biological activity that occurs within the brain is employed to give people a better understanding of the thought process of individuals who engage in psychic numbing.

Studies have also focused on the habituation of the rostral anterior cingulate cortex (rACC). The rACC is part of the limbic system, which is responsible for emotional processing. It is hypothesized that the rACC determines the, "correct allocation of attention based resources to emotionally aversive stimuli". This means it may play an active role in identifying important behavioral responses necessary to comprehend the consequences of the aversive stimuli. The limbic system also includes areas that are important for memory consolidation. The relationship between all the areas in the limbic system is an area of interest for psychic numbing because it encapsulates two factors that contribute to the phenomenon: emotions and memory. These studies are also a good paradigm for the understanding of psychic numbing because they considers sustained aversive material and how the brain reacts in a habitual manner in an effort to remove the underlying emotional content.

Neuropsychophysiology

Cortisol helps regulate the stress response via the negative feedback loop, which are activated when a person is subjected to specific situations that trigger the relationship between the emotionally charged memories of the traumatic event and the observable autonomic responses.

Stress can also be considered a brain-body reaction due to external or internal cues this can include the environment as well as memory. The areas of the brain that communicate with one another are the prefrontal cortex, amygdala, hippocampus, nucleus accumbens, and the hypothalamus. Through a series of feedback processes, the release of specific neurotransmitters as well as neuromodulators occurs.

MRI posterior cingulate

Norepinephrine (NE) is released by the Locus coeruleus, it is then transferred to the limbic system where much of the memory consolidation and fight or flight responses are facilitated.

Adrenocorticotropin (ACTH) is released from the anterior pituitary, which triggers the release of glucocorticoids from the adrenals. The chronic exposure to stress affects organisms that deal with daily activities and it also interferes with one's coping mechanisms.

Once the HPA axis is activated, it triggers an increase in glucocorticoids. Once these hormones cross the blood–brain barrier, they interact with other neurotransmitters and change the brain's chemistry as well as structure.

The process of habituation is important to consider because it is a prevalent variable in the phenomenon of psychic numbing. The constant exposure a society or individual has to a prolonged and sustained aversive stimuli, the emotional magnitude that the stimuli has decreases greatly over time to where it becomes unnoticeable to those who have been surrounded by it for a long period of time. This type of response is seen in Vietnam veterans and rape victims who suffer from PTSD.

Additionally, studies describe the importance of the rACC and the cingulate cortex for comprehension and the feeling of a painful stimulus. Taiwanese and American researchers recorded brain-wave readings from participants as the researchers observed body parts pricked with a pin, or dabbed with a Q-tip. Half of the subjects were physicians and the other half was a control group. The control group showed clear differences in his or her reactions to the pin-prick in comparison to the Q-tip. The physicians, who previously had experience managing sickness and pain, did not. The authors of the study theorized that the physicians unconsciously numbed their reaction to the pain of the pin-prick due to his or her profession. This may be a beneficial result because physicians need to block out the pain response and use more cognitive resources necessary for being of assistance in a time of need. This further suggests the individual differences people have in regards to psychic numbing and the deviation away from more tragic accounts of rape and PTSD. This type of desensitization is not independent of the participant's lives, instead it is a result of years of experience woven into his or her daily lives, resulting in a numbed response. Figures of areas of the control group's brains showed activation in the rACC, and the physician's brains did not, suggesting there was already habituation.

Conceptualizations

Normative graphs of the value of life saving

The original view of psychic numbing dealt with human extinction and the mass response to potentially life-threatening scenarios. Lifton argued the worry for these events was low and therefore generated an equally low probability of occurrence point of view. This repeated exposure makes humans numb to the possibility that an event of that nature can occur. However, when asked to recall the probability that mass extinction will occur, people have a tendency to think counter-intuitively and rate the probability as high when it is in fact low and behaviorally respond opposite to his or her rating.

Additionally, much of the individualist view comes from studying the behavioral traits of people who suffer from PTSD. Focus groups, clinical cases, as well as religion play a crucial role in one's ability to cope with the stress of traumatic stimuli. Many studies have been conducted that address the value of these therapeutic interventions as well as their efficacy. There is a strong connection to depersonalization, emotional numbing, as well as dissociation from one's identity. This shows the shift of psychic numbing from a collectivist view to an individualistic view.

Collectivist

See also: Identifiable victim effect

Robert Jay Lifton spearheaded the psychic numbing movement and his concentration was on a much larger scale. Psychic numbing is about the way a culture or society withdraws from issues that would otherwise be too overwhelming for the human mind to comprehend. In this respect, psychic numbing is a societal reaction to impending doom, chaos, and ultimately mankind's extinction.

Paul Slovic, a prominent psychologist in the realm of risk, maintains the original interpretation posited by Lifton. Slovic's article, "Psychic Numbing and Mass Atrocity", returns to the collectivist model and most notably confronts the value of saving a human's life. The figures to the right denote both arguments for the hypothesized value of saving a human's life as well as the true value of saving a human's life established through Slovic's empirical research. Slovic introduced the concept of psychophysical numbing, which is the diminished sensitivity to the value of life and an inability to appreciate loss. Essentially, the proportion of lives saved is more important than the number of lives saved. One of Slovic's arguments for this outcome is that people suffer from innumeracy and cannot comprehend the emotional connotation associated with large numbers. The threshold, as stated by Slovic, where people cannot comprehend the emotional magnitude of the loss of life is two, as shown in the figure. Paul and researchers say findings can be summarized with "The more who die, the less we care."

Graph of the value of saving a human life

Slovic also points to Weber's law, which states the difference between two stimuli is proportional to the magnitude of the stimuli. Additionally, Weber's law focuses on the just-noticeable difference between the two stimuli. Slovic addressed Weber's law from a different context - he considered the magnitude and value of a human life. Slovic took Weber's law and incorporated prospect theory, which is decision making based on potential gains and losses, not the actual outcome. Slovic found that when prospect theory and Weber's law are analyzed in regards to human life, the value of saving human lives is greater for a smaller tragedy than for a larger one.

These are all considered collectivist views of psychic numbing because they encapsulate a general theory of mind held by the majority of citizens in a society. Additionally, these views remain consistent with the original concept of which collective avoidance and attention withdrawal becomes the active state of mind in regards to potential threats of mass extinction.

Individualist

Psychic numbing, as it shifts away from the collectivist view, is a common characteristic of people who suffer from PTSD. A general definition of psychic numbing is a diminished response to the external world. There are three elements that attribute to psychic numbing:

1. Loss of interest in activity
2. detachment from others
3. restricted range of affect

These two mechanisms promote the inability to engage emotionally with a traumatic memory (acceptance), thus impairing the process of recovery.

Susan Gill bridges the disciplines of social psychology and neuropsychology in her analysis of psychic numbing by explaining that there are notable behavioral changes, the most typical trait is being zombie-like and in a "dead-zone".

• The relationship between being overwhelmed and completely shutting down.

The state of being overwhelmed is different than complete shut-down. Overwhelmed responses follow moderate to prolonged stressful states and result in an active effort to regain control.

• The neurochemical states associated with dissociative behavior are not metabolized, that is they become perpetual and frozen in time, which causes the deviation from normal behavior.

The very anatomy of the brain can be manipulated under extreme cases of psychic numbing. The neurochemical reactions fail to metabolize and result in lack of synaptic connections and neuronal firing with no dendritic connections. There is also a loop of the same information that fails to connect with other areas of the brain, which results in the inability to get out of the "dead-zone".

Religion

Religion is also considered to be an internalized coping mechanism. The role of religious values in coping with life-threatening illnesses is another individualistic trait that people use to cope with the behavioral side-effects associated with the diseases. Depersonalization is a very prominent behavioral trait associated with cancer patients. Findings show that people with cancer cope no worse than non-cancer patients. Cancer patients tend to blunt his or her experiences as a means of handling a painful reality. Avoidance and denial are typical tendencies of psychic numbing. Cancer patients also report a self-distancing mechanism, and take on a third-person perspective as a means of dealing with the life-threatening disease. It is argued that putting one's life within a framework of religion is a very important part of the coping process. This religious framework helps the patients understand that some things are out of one's control. As discussed earlier, a lack of control over one's stressful stimuli generates a degree of psychic numbing. However, by putting his or her life-threatening disease within a religious framework takes the mystery out of the disease and adds a sense of control. As discussed earlier, the perceived sense of control as well as actual control are important contributors to adequately coping with psychic numbing.

As described earlier, research on psychic numbing has suggested that people who become desensitized to suffering may be more adept in dealing with an upsetting or dangerous situation.

Nuclear denial disorder

Many individuals fail to react effectively to the overwhelming threat of annihilation by nuclear warfare, and in 1987 Thomas C. Wear termed this nuclear denial disorder, a type of psychic numbing. It involves the over-use of a denial defense mechanism, and "an apathetic business-as-usual attitude toward the threat of nuclear annihilation". Michael D. Newcomb viewed nuclear denial as an avoidant response to quite justifiable nuclear anxiety.