ratio of word probabilities predicted from brain for eye and bell

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eye

bell

top 10 words in brain distribution (in article):
water form surface land region cause time type world zone
top 10 words in brain distribution (in article):
produce wine contain state common time world type process century
top 10 words in brain distribution (not in article):
ice rock river sea wind ocean soil flow lake occur
top 10 words in brain distribution (not in article):
light plant drink fruit lamp water beer seed grow sugar
times more probable under eye 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under bell
(words not in the model)
Eyes'" are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, mollusks, chordates, annelids and arthropods. The simplest "eyes", in even unicellular organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment. Overview. Complex eyes can distinguish shapes and colors. The visual fields of many organisms, especially predators, involve large areas of binocular vision to improve depth perception; in other organisms, eyes are located so as to maximise the field of view, such as in rabbits and horses. The first proto-eyes evolved among animals 540 million years ago, about the time of the so-called Cambrian explosion. The last common ancestor of animals possessed the biochemical toolkit necessary for vision, and more advanced eyes have evolved in 96% of animal species in 6 of the thirty-something main phyla. In most vertebrates and some mollusks, the eye works by allowing light to enter it and project onto a light-sensitive panel of cells, known as the retina, at the rear of the eye. The cone cells (for color) and the rod cells (for low-light contrasts) in the retina detect and convert light into neural signals for vision. The visual signals are then transmitted to the brain via the optic nerve. Such eyes are typically roughly spherical, filled with a transparent gel-like substance called the vitreous humour, with a focusing lens and often an iris; the relaxing or tightening of the muscles around the iris change the size of the pupil, thereby regulating the amount of light that enters the eye, and reducing aberrations when there is enough light. The eyes of cephalopods, fish, amphibians and snakes usually have fixed lens shapes, and focusing vision is achieved by telescoping the lens similar to how a camera focuses. Compound eyes are found among the arthropods and are composed of many simple facets which, depending on the details of anatomy, may give either a single pixelated image or multiple images, per eye. Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors, which are arranged hexagonally, and which can give a full 360-degree field of vision. Compound eyes are very sensitive to motion. Some arthropods, including many Strepsiptera, have compound eyes of only a few facets, each with a retina capable of creating an image, creating vision. With each eye viewing a different thing, a fused image from all the eyes is produced in the brain, providing very different, high-resolution images. Possessing detailed hyperspectral color vision, the Mantis shrimp has been reported to have the world's most complex color vision system. Trilobites, which are now extinct, had unique compound eyes. They used clear calcite crystals to form the lenses of their eyes. In this, they differ from most other arthropods, which have soft eyes. The number of lenses in such an eye varied, however: some trilobites had only one, and some had thousands of lenses in one eye. In contrast to compound eyes, simple eyes are those that have a single lens. For example, jumping spiders have a large pair of simple eyes with a narrow field of view, supported by an array of other, smaller eyes for peripheral vision. Some insect larvae, like caterpillars, have a different type of simple eye (stemmata) which gives a rough image. Some of the simplest eyes, called ocelli, can be found in animals like some of the snails, which cannot actually "see" in the normal sense. They do have photosensitive cells, but no lens and no other means of projecting an image onto these cells. They can distinguish between light and dark, but no more. This enables snails to keep out of direct sunlight. In organisms dwelling near deep-sea vents, compound eyes have been secondarily simplified and adapted to spot the infra-red light produced by the hot vents in this way the bearers can spot hot springs and avoid being boiled alive. Evolution. Visual pigments appear to have a common ancestor and were probably involved in circadian rhythms or reproductive timing in simple organisms. Complex vision, associated with dedicated visual organs, or eyes, evolved many times in different lineages. Types of eye. Nature has produced ten different eye layouts indeed every way of capturing an image has evolved at least once in nature, with the exception of zoom and Fresnel lenses. Eye types can be categorized into "simple eyes", with one concave chamber, and "compound eyes", which comprise a number of individual lenses laid out on a convex surface. Note that "simple" does not imply a reduced level of complexity or acuity. Indeed, any eye type can be adapted for almost any behaviour or environment. The only limitations specific to eye types are that of resolution the physics of compound eyes prevents them from achieving a resolution better than 1°. Also, superposition eyes can achieve greater sensitivity than apposition eyes, so are better suited to dark-dwelling creatures. Eyes also fall into two groups on the basis of their photoreceptor's cellular construction, with the photoreceptor cells either being cilliated (as in the vertebrates) or rhabdomic. These two groups are not monophyletic; the cnidaira also possess cilliated cells, Pit eyes. Pit eyes, also known as stemma, are eye-spots which may be set into a pit to reduce the angles of light that enters and affects the eyespot, to allow the organism to deduce the angle of incoming light. Found in about 85% of phyla, these basic forms were probably the precursors to more advanced types of "simple eye". They are small, comprising up to about 100 cells covering about 100 µm. The directionality can be improved by reducing the size of the aperture, by incorporating a reflective layer behind the receptor cells, or by filling the pit with a refractile material. Pinhole eye. The pinhole eye is an "advanced" form of pit eye incorporating these improvements, most notably a small aperture (which may be adjustable) and deep pit. It is only found in the nautiloids. Without a lens to focus the image, it produces a blurry image, and will blur out a point to the size of the aperture. Consequently, nautiloids can't discriminate between objects with an angular separation of less than 11°. Shrinking the aperture would produce a sharper image, but let in less light. Spherical lensed eye. The resolution of pit eyes can be greatly improved by incorporating a material with a higher refractive index to form a lens, which may greatly reduce the blur radius encountered hence increasing the resolution obtainable. The most basic form, still seen in some gastropods and annelids, consists of a lens of one refractive index. A far sharper image can be obtained using materials with a high refractive index, decreasing to the edges this decreases the focal length and thus allows a sharp image to form on the retina. This also allows a larger aperture for a given sharpness of image, allowing more light to enter the lens; and a flatter lens, reducing spherical aberration. Such an inhomogeneous lens is necessary in order for the focal length to drop from about 4 times the lens radius, to 2.5 radii. Heterogeneous eyes have evolved at least eight times four or more times in gastropods, once in the copepods, once in the annelids and once in the cephalopods. No aquatic organisms possess homogeneous lenses; presumably the evolutionary pressure for a heterogeneous lens is great enough for this stage to be quickly "outgrown". This eye creates an image that is sharp enough that motion of the eye can cause significant blurring. To minimize the effect of eye motion while the animal moves, most such eyes have stabilizing eye muscles. The ocelli of insects bear a simple lens, but their focal point always lies behind the retina; consequently they can never form a sharp image. This capitulates the function of the eye. Ocelli (pit-type eyes of arthropods) blur the image across the whole retina, and are consequently excellent at responding to rapid changes in light intensity across the whole visual field this fast response is further accelerated by the large nerve bundles which rush the information to the brain. Focussing the image would also cause the sun's image to be focussed on a few receptors, with the possibility of damage under the intense light; shielding the receptors would block out some light and thus reduce their sensitivity. This fast response has led to suggestions that the ocelli of insects are used mainly in flight, because they can be used to detect sudden changes in which way is up (because light, especially UV light which is absorbed by vegetation, usually comes from above). Weaknesses. One weakness of this eye construction is that chromatic aberration is still quite high although for organisms without color vision, this is a very minor concern. A weakness of the vertebrate A bell'" is a simple sound-making device. The bell is a percussion instrument and an idiophone. Its form is usually an open-ended hollow drum which resonates upon being struck. The striking implement can be a tongue suspended within the bell, known as a "clapper", a small, free sphere enclosed within the body of the bell, or a separate mallet. Bells are usually made of cast metal, but small bells can also be made from ceramic or glass. Bells can be of all sizes: from tiny dress accessories to church bells weighing many tons. Church and temple bells. In the Western world, its most classical form is a church bell or town bell, which is hung within a tower and sounded by having the entire bell swung by ropes, whereupon an internal hinged clapper strikes the body of the bell (called a free-swinging bell). A set of bells, hung in a circle for change ringing, is known as a ring of bells. In the Eastern world, the traditional forms of bells are temple and palace bells, small ones being rung by a sharp rap with a stick, and very large ones rung by a blow from the outside by a large swinging beam. The striking technique is employed worldwide for some of the largest tower-borne bells, because swinging the bells themselves could damage their towers. In the Roman Catholic Church and among some High Lutherans and Anglicans, small hand-held bells, called Sanctus or sacring bells, are often rung by a server at Mass when the priest holds high up first the host, and then the chalice immediately after he has said the words of consecration over them (the moment known as the Elevation). This serves to indicate to the congregation that the bread and wine have just been transformed into the body and blood of Christ (see transubstantiation), or, in the alternative Reformation teaching, that Christ is now bodily present in the elements, and that what the priest is holding up for them to look at is Christ himself (see consubstantiation). Japanese religious bells. Japanese Shintoist and Buddhist bells are used in religious ceremonies. "Suzu", a homophone meaning both "cool and refreshing," are spherical bells which contain metal pellets that produce sound from the inside. The hemispherical bell is the "Kane" bell, which is struck on the outside. See also Kane (musical instrument). Buddhist bells. Buddhist bells are used in religious ceremonies. Bell construed as a cause for war. On January 15, 1602 ("Keichō 7"), a fire broke out at Hōkō-ji, Buddhist temple complex in Kyoto. The great image of the Buddha and the structure housing the statue, the "Daibutsu-den", were both consumed by the flames. In 1610, Toyotomi Hideyori decided to sponsor rebuilding the Hōkō-ji and he also decided to order a great bell cast in bronze. On August 24, 1614 ("Keichō 19"), the huge new bronze bell was cast successfully. Dedication ceremonies were scheduled, but at the last minute, Tokugawa Ieyasu forbade the ceremonies to take place because he construed inscriptions on the bell to have been a personal affront: This contrived dispute led to the, which was a series of battles between armies of the Tokugawa shogunate and the samurai of the Toyotomi clan. The siege lasted through 1615. It is conventionally divided into two stages: the Winter Campaign and the Summer Campaign. In the end, the total destruction of the Toyotomi eliminated the last major opposition to the shogunate which would come to dominate Japan for the next 250 years. Bellmaking. The process of casting bells is called bellmaking or bellfounding, and in Europe dates to the 4th or 5th century. The traditional metal for these bells is a bronze of about 23% tin. Known as "bell metal", this alloy is also the traditional alloy for the finest Turkish and Chinese cymbals. Other materials sometimes used for large bells include brass and iron. Bells are always cast mouth down. Bells are made to exact formulas, so that given the diameter it is possible to calculate every dimension, and its musical note, or tone. The frequency of a bell's note in Hz varies with the square of its thickness, and inversely with its diameter. Much experimentation has been devoted to determining the exact shape that will give the best tone. The thickness of a church bell at its thickest part, called the 'sound bow' is usually one thirteenth its diameter. If the bell is mounted as cast, it is called a "maiden bell" while "tuned bells" are worked after casting to produce a precise note. Bell towers. Bells are also associated with clocks, indicating the hour by ringing. Indeed, the word "clock" comes from the Latin word "cloca", meaning bell. Clock towers or bell towers can be heard over long distances which was especially important in the time when clocks were too expensive for widespread use. In the case of clock towers and grandfather clocks, a particular sequence of tones may be played to represent the hour. One common pattern is called the "Westminster Quarters," a sixteen-note pattern named after the Palace of Westminster which popularized it as the measure used by "Big Ben". Bells as musical instruments. Some bells are used as musical instruments, such as carillons, (clock) chimes, or ensembles of bell-players, called bell choirs, using hand-held bells of varying tones. A "ring of bells" is a set of 4 to twelve bells or more used in change ringing, a particular method of ringing bells in patterns. A peal in changing ringing may have bells playing for several hours, playing 5,000 or more patterns without a break or repetition.. Ancient Chinese bells. The ancient Chinese bronze chime bells called bianzhong or (鐘) are among the highest achievements of Chinese bronze casting technology. These chime bells were used as polyphonic musical instruments and some of these bells have been dated at between 2000 to 3600 years old. The secret of the design and the method of casting zhong bells, which was known only to the Chinese in antiquity, was lost in later generations. It was not fully rediscovered and understood until 1978, when a complete ceremonial set of 65 "zhong" bells was found in a near-perfect state of preservation during the excavation of the of Marquis Yi, who died ca. 430BCE. Yi was ruler of Zeng, one of the Warring States which at the time of his death was under control of the Chǔ state. This region is now part of the present-day Hubei province. Although tuned bells have been created and used for musical performance in many cultures, zhong are unique among all other types of cast bells in several respects. They have a lens-shaped (rather than circular) section and the bell mouth has a distinctive "cutaway" profile, and this special shape gives zhong bells the remarkable ability to produce, depending on where they are struck. The interval between these notes on each bell is either a major or minor third, equivalent to a distance of four or five notes on a piano.. The bells of Marquis Yi, which are still fully playable after almost 2500 years, cover a range of slightly less than five octaves but thanks to their twin-tone capability, the set can sound a complete 12-tone scale, predating the development of the European 12-tone system by some 2000 years, and can play melodies in diatonic and pentatonic scales These bells usually have inscriptions on them from which scholars used as references for studying ancient Chinese writings (also known as Bronzeware script). Another related ancient Chinese musical instrument is called qing (pinyin qing4) but it was made of stone instead of metal. Konguro'o. Konguro'o is a small bell, which as well as Djalaajyn firstly had the utilitarian purposes and only after artistic ones. Konguro'o sounded by the time of moving to the new places, being fastened to the horse harness it created very specific "smart" sound background. Konguro'o also hanged on the neck of leader goat, which leads the flock of sheep in some definite direction. That is why in folk memory almost magic sound of konguro'o was associated with nomadic mode of life. To make this instrument Kyrgyz foremen used cooper, bronze, iron and brass. They also decorated it with artistic carving and covered with silver. Sizes of the instruments might vary in considerable limits, what depended on its function. Every bell had its own timbre. Chimes. A variant on the bell is the tubular bell. Several of these metal tubes which are struck manually with hammers, form an instrument named "tubular bells" or "chimes". In the case of wind or aeolian chimes, the tubes are blown against one another by the wind. Farm bells. Whereas the church and temple bells called to mass or religious service, bells were used on farms for more secular signaling. The greater farms in Scandinavia usually had a small bell-tower resting on the top of the barn. The bell was used to call the workers from the field at the end of the day's work. In folk tradition, it is recorded that each church and possibly several farms had their specific rhymes connected to the sound of the specific bells. An example is the Pete Seeger song "The Bells of Rhymney".