Long, Crawford Williamson, 1815-78, American physician, b. Danielsville, Ga., M.D. Univ. of Pennsylvania, 1839. He practiced in Jefferson, Ga. In 1842 he excised a tumor of the neck using ether anesthesia, but this was not made public until after the demonstration by W. T. G. Morton in Boston in 1846.

Long, Earl Kemp, 1895-1960, American political figure, b. Winnfield, La.; brother of Huey Long. A lawyer, he was given a state office when his brother became governor. He ran for lieutenant governor in 1931 without Huey Long's support and lost. Later, the two were reconciled. In 1936, he was elected lieutenant governor and served (1939-40) as governor, after his predecessor resigned. Although defeated for reelection in 1940, he twice again served as governor of Louisiana (1948-52, 1956-60). From 1935 to 1960, he was a leader in the "Long machine" created by his brother, which dominated Louisiana politics after 1928. His last administration was marred by personal troubles, which at one point caused him to be committed to a mental hospital. Running unopposed as the Democratic candidate for the U.S. House of Representatives in 1960, he died before the general election took place.

Long, Huey Pierce, 1893-1935, American political leader, b. Winnfield, La.; brother of Earl Long. Originally a farm boy, he was an extremely successful traveling salesman before studying law at Tulane Univ. He was admitted to the bar in 1915 and practiced in Winnfield and Shreveport. Long was elected to the Louisiana railroad commission in 1918; in 1921 it became the public service commission. He was reelected to the commission in 1924, served as chairman, and was attorney for the state in public utility litigation.

Narrowly defeated for governor of Louisiana in 1924, Long was swept into office four years later. When the state legislature obstructed his program of economic and social reform, he severely lessened the influence of the moneyed oligarchy that had dominated Louisiana government since Reconstruction and established his own control of the state through extensive use of patronage. Long was responsible for the building of badly needed roads and bridges, the expansion of state-owned hospitals, and the extension of the school system into remote rural regions. He also increased the taxes of large Louisiana businesses, especially the oil companies. The state legislature was bludgeoned or bought into passing his laws. In 1929, Long was impeached on charges of bribery and gross misconduct, but he was not convicted.

"The Kingfish," as Long was called, was elected to the U.S. Senate in 1930, but he did not take his seat until Jan., 1932, after he had assured the succession as governor of one of his own supporters. From Washington, Long continued to direct the Louisiana government. In 1934 he began a reorganization of the state, which virtually abolished local government and gave Long the power to appoint all state employees. As a senator, Long was at first a supporter of the New Deal, but soon became one of Franklin Delano Roosevelt's most vociferous critics.

A presidential aspirant, Long gained a steadily increasing national following. Early in 1934 he introduced his plan for national social and economic reform, the "Share-the-Wealth" program; it proposed a guaranteed family annual income and a homestead allowance for every family. Meanwhile, in Louisiana, Long continued to expand his powers. In Sept., 1935, on a trip to the state, Long was assassinated. The assassin, Dr. Carl A. Weiss, was slain by Long's bodyguards. Long's political machine flourished for several years after his death, and the Long family remained important in the state.

His son, Russell Billiu Long, 1918-2003, b. Shreveport, La., was also a politician. A graduate of the Louisiana State University (1941) and its law school (1942), he served (1948-87) as U.S. senator from Louisiana. A Democrat, he was the longtime chairman of the Senate's finance committee and was important in the creation of tax laws. His last significant accomplishment was helping to write simplified national income tax legislation in 1986.

Long, John Luther, 1861-1927, American playwright, b. Hanover, Pa. In 1900, in collaboration with David Belasco, he dramatized his short story "Madame Butterfly" (1897), which Puccini later made (1906) into an opera. Belasco and Long also collaborated successfully on The Darling of the Gods (1902) and Adrea (1905).

Long, Stephen Harriman, 1784-1864, American explorer, b. Hopkinton, N.H. As an army engineer, Long was sent on several exploring and surveying expeditions. The first in 1817 was to the region of the upper Mississippi and the Fox-Wisconsin portage; it is recorded in his Voyage in a Six-oared Skiff to the Falls of St. Anthony (1860). A journey to the Rocky Mts. in 1819-20 provided much new knowledge of the mountains. He climbed several peaks, including Long's Peak, and explored the regions of the Platte and Arkansas rivers. Edwin James's Account of an Expedition from Pittsburgh to the Rocky Mountains (2 vol. and an atlas, 1822-23) tells of that journey. In 1823, Long led an expedition to determine the source of the Minnesota River and to study the United States-Canadian boundary W of the Great Lakes. Some of his notes were used in W. H. Keating's Narrative of an Expedition to the Source of the St. Peter's River (1824). Chosen to select a route for the Baltimore and Ohio RR, he made a survey that resulted in an authoritative railroad manual, with tables of grades and curves.

Long, Loch, inlet of the Firth of Clyde, extending from northeast to southwest in Argyll and Bute, W Scotland. Oil is imported there and piped 57 mi (92 km) to the Grangemouth refinery.

In track and field, any foot race over 5,000 m in length. Marathons and cross-country running are also considered long-distance events. Women rarely ran in races beyond 3,000 m until the late 20th century.

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or broad jump

Track-and-field sport consisting of a horizontal jump for distance. It was formerly performed from both standing and running starts, as separate events, but the standing long jump is no longer included in major competitions. The running long jump was an event in the Olympic Games of 708 BC and in the modern Games from 1896. In 1948 the women's long jump became an Olympic event.

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Traditional communal dwelling of the Iroquois Indians until the 19th century. The longhouse was a rectangular box built out of poles, with doors at each end and saplings stretched over the top to form the roof, the whole structure being covered with bark. It was about 20 ft (6 m) wide and could be more than 200 ft (60 m) in length, depending on the number of families living in it. Down the middle of the house were fires, which were shared by families on either side. The term is also applied today to an Iroquois building designated as church and meeting hall, though its form is entirely different. Seealso pole construction.

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(born Aug. 30, 1893, near Winnfield, La., U.S.—died Sept. 10, 1935, Baton Rouge, La.) U.S. politician. Despite an impoverished background, he managed to obtain enough formal schooling to pass the bar in 1915. Politically ambitious, he was elected state railroad commissioner at 25. His call for state regulation of the utilities and his attacks on the Standard Oil Company won him widespread popularity. As governor (1928–31) of Louisiana, he became nationally famous for his fiery oratory and unconventional behaviour, and his nickname, “Kingfish,” became widely known. He implemented public works projects and education reform but used autocratic methods to control the state government. Elected to the U.S. Senate (1932–35), he sought national power with a Share-the-Wealth program. In 1935 he was assassinated by Carl A. Weiss, whose father Long had vilified. His brother Earl K. Long (1895–1960) later served as governor (1939–40, 1948–52, 1956–60).

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Session of the English Parliament summoned in November 1640 by Charles I, so named to distinguish it from the Short Parliament of April–May 1640. Charles called the session to raise the money needed for his war against the Scots. Resistant to Charles's demands, the Parliament caused the king's advisers to resign and passed an act forbidding its own dissolution without its members' consent. Tension between the king and Parliament increased until the English Civil War broke out in 1642. After the king's defeat (1646), the army, led by Thomas Pride, exercised political power and in 1648 expelled all but 60 members of the Long Parliament. The remaining group, called the Rump, brought Charles to trial and execution (1649); it was forcibly ejected in 1653. In 1659, after the end of Oliver Cromwell's protectorate, the Parliament was reestablished; those who were excluded in 1648 were restored to membership. The Parliament dissolved itself in 1660.

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Body of water between the southern shore of Connecticut and the northern shore of Long Island, New York, U.S. It connects with the East River and with Block Island Sound. Covering 1,180 sq mi (3,056 sq km), it is 90 mi (145 km) long and 3–20 mi (5–32 km) wide. Its shores have many residential communities and summer resorts.

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Island (pop., 2000: 7,448,618), southeastern New York, U.S., lying between Long Island Sound and the Atlantic Ocean. It has four counties: Kings, Queens, Nassau, and Suffolk. Kings County (the borough of Brooklyn) and Queens County (the borough of Queens) form part of New York City. At its western end it is separated from the Bronx and Manhattan by the East River and from Staten Island by the Narrows. It is 118 mi (190 km) long, 12–23 mi (19–37 km) wide, and has an area of 1,401 sq mi (3,629 sq km). Its eastern portion has many beaches; it serves as a recreation area for New York City. Its southern shore, lined by sand spits (see Fire Island), shelters several bays, including Jamaica Bay. Originally inhabited by Indians (mostly Delaware), it was included in a grant to the Plymouth Co. It was settled by Dutch and English, but the whole island became part of the British colony of New York in 1664. It was the site of the Battle of Long Island (Aug. 27, 1776), an American defeat in the American Revolution.

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City (pop., 2000: 461,522), southwestern California, U.S. The site was originally an Indian trading camp, and Spanish ranches were located there in the 18th century. Laid out as Willmore City in 1880 and incorporated in 1888, it was renamed for its 8.5-mi (13.5-km) beach. The discovery of oil nearby in 1921 led to rapid growth. An earthquake in 1933 caused extensive damage. It is connected to the Los Angeles harbour by the Cerritos Channel. The British ocean liner Queen Mary has been moored in the harbour since 1969.

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(born Aug. 30, 1893, near Winnfield, La., U.S.—died Sept. 10, 1935, Baton Rouge, La.) U.S. politician. Despite an impoverished background, he managed to obtain enough formal schooling to pass the bar in 1915. Politically ambitious, he was elected state railroad commissioner at 25. His call for state regulation of the utilities and his attacks on the Standard Oil Company won him widespread popularity. As governor (1928–31) of Louisiana, he became nationally famous for his fiery oratory and unconventional behaviour, and his nickname, “Kingfish,” became widely known. He implemented public works projects and education reform but used autocratic methods to control the state government. Elected to the U.S. Senate (1932–35), he sought national power with a Share-the-Wealth program. In 1935 he was assassinated by Carl A. Weiss, whose father Long had vilified. His brother Earl K. Long (1895–1960) later served as governor (1939–40, 1948–52, 1956–60).

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Long-term memory (LTM) is memory that can last as little as a few days or as long as decades. It differs structurally and functionally from working memory or short-term memory, which ostensibly stores items for only around 20 seconds. Biologically, short-term memory is a temporary potentiation of neural connections that can become long-term memory through the process of rehearsal and meaningful association. Much is not known about the underlying biological mechanisms of long-term memory, but the process of long-term potentiation, which involves a physical change in the structure of neurons, has been proposed as the mechanism by which short-term memories move into long-term storage. Notably, the time scale involved at each level of memory processing remains under investigation.

As long-term memory is subject to fading in the natural forgetting process, several recalls/retrievals of memory may be needed for long-term memories to last for years, dependent also on the depth of processing. Individual retrievals can take place in increasing intervals in accordance with the principle of spaced repetition. This can happen quite naturally through reflection or deliberate recall (a.k.a. recapitulation or recollection), often dependent on the perceived importance of the material.

Capacity

The brain stores long term information by growing additional synapses between neurons. Since the brain has approximately 10¹⁵ synapses, one can argue that brain has a maximum capacity of about 100 TByte, possibly more if one synapse can store more than 1 bit of information. By no means do humans store that much information. Experiments in the mid 1980s showed that humans can store only 1-2 bits/second in their long term memory. The cumulative amount of data stored in the brain over a 70 year lifetime is therefore only in the order of 125 MByte.

Duration

Studies undertaken by Bahrick et al can predict that long term memory can indeed remember certain information for almost a lifetime. However factors can in fact reduce or extinguish information completely. Childhood amnesia is a factor effecting long term memories duration, there are very few people who can remember information or events before the age of 3 or 4.

Encoding of information

Long term memory encodes information semantically for storage, as researched by Baddeley.

Sleep

Some theories consider sleep to be an important factor in establishing well-organized long-term memories. (See also sleep and learning.)

According to Tarnow's theory, long term memories are stored in dream format (reminiscent of the Penfield & Rasmussen’s findings that electrical excitations of cortex give rise to experiences similar to dreams). During waking life an executive function interprets long term memory consistent with reality checking (Tarnow, 2003).

Types of memory

The brain does not store memories in one unified structure, as might be seen in a computer's hard disk drive. Instead, different types of memory are stored in different regions of the brain. LTM is typically divided up into two major headings: declarative memory and implicit memory (or procedural memory).

1. Declarative memory refers to all memories that are consciously available. These are encoded by the hippocampus, entorhinal cortex, and perirhinal cortex, but consolidated and stored elsewhere in the cortex. The precise location of storage is unknown, but the temporal cortex has been proposed as a likely candidate. Declarative memory also has two major subdivisions:
• Episodic memory refers to memory for specific events in time
• Semantic memory refers to knowledge about the external world, such as the function of a pencil.
2. Procedural memory refers to the use of objects or movements of the body, such as how exactly to use a pencil or ride a bicycle. This type of memory is encoded and probably stored by the cerebellum and the striatum.

There are various other categorizations of memory and types of memory that have captured research interest. Prospective memory (its complement: retrospective memory) is an example.

Emotional memory, the memory for events that evoke a particularly strong emotion, is another. Emotion and memory is a domain that can involve both declarative and procedural memory processes. Emotional memories are consciously available, but elicit a powerful, unconscious physiological reaction. They also have a unique physiological pathway that involves strong connections from the amygdala into the prefrontal cortex, but much weaker connections running back from the prefrontal cortex to the amgydala.

Disorders of memory

Minor everyday slips and lapses of memory are fairly commonplace, and may increase naturally with age, when ill, or when under stress (Reason J.). Some women may experience more memory lapses following the onset of the menopause. More serious problems with memory generally occur due to traumatic brain injury or neurodegenerative disease :

Everyday memory problems

The everyday experience of memory problems is the problem of failed recall, forgetting. The tip-of-the-tongue phenomenon is particularly frustrating because the person trying to remember feels that the memory is available. Failing to remember something in the situation in which it would have been useful leads to regret.

Traumatic brain injury

The majority of findings about memory have been the result of studies that lesioned specific brain regions in rats or primates, but some of the most important work has been the result of accidental or inadvertent brain trauma. The most famous case in memory studies is the case study of HM, who had parts of his hippocampus, parahippocampal cortices, and surrounding tissue removed in an attempt to cure his epilepsy. His subsequent total anterograde amnesia and partial retrograde amnesia provided the first evidence for the localization of memory function, and further clarified the differences between declarative and procedural memory.

Neurodegenerative diseases

Many neurodegenerative diseases can cause memory loss. Some of the most prevalent (and consequently, most intensely researched) include Alzheimer's Disease, Dementia, Huntington's Disease, Multiple Sclerosis, and Parkinson's Disease. None act specifically on memory; instead memory loss is often a casualty of generalized neuronal deterioration. Currently, these illnesses are irreversible, but research into stem cells, psychopharmacology, and genetic engineering hold much promise.

Biological underpinnings at the cellular level

Long term memory is dependent upon the construction of new proteins within the cellular body, particularly transmitters, receptors, and new synapse pathways that reinforce the communicative strength between neurons. The production of new proteins devoted to synapse reinforcement is triggered after the release of certain signaling substances (such as calcium within hippocampal neurons) in the cell. In the case of hippocampal cells, this release is dependent upon the expulsion of magnesium (a binding molecule) that is expelled after significant and repetitive synaptic signaling. The temporary expulsion of magnesium frees NMDA receptors to release calcium in the cell, a signal that leads to gene transcription and the construction of reinforcing proteins. Neihoff, Debra (2005) "The Language of Life 'How cells Communicate in Health and Disease'" Speak Memory, 210-223. For more information see long-term potentiation (LTP).

One of the newly synthesized proteins in LTP is also critical for maintaining long-term memory. This protein is an autonomously active form of the enzyme protein kinase C (PKC), known as PKMζ. PKMζ maintains the activity-dependent enhancement of synaptic strength and inhibiting PKMζ erases established long-term memories, without affecting short-term memory or, once the inhibitor is eliminated, the ability to encode and store new long-term memories is restored.

Also BDNF is important for the persistence of long-term memories.

References

See also

• Aging and memory
• Emotion and memory
• Long-term potentiation
• Contrast Short-term memory