ratio of word probabilities predicted from brain for eye and spoon

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eye

spoon

top 10 words in brain distribution (in article):
water light animal form time type cause produce surface region
top 10 words in brain distribution (in article):
produce sugar time form food common state type century head
top 10 words in brain distribution (not in article):
ice drink rock lamp river flow occur state wine soil
top 10 words in brain distribution (not in article):
plant fruit fuel grow seed oil engine leaf tree species
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 spoon
(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 A spoon'" is a utensil consisting of a small shallow bowl, oval or round, at the end of a handle. A type of cutlery (usually called flatware in the United States), especially as part of a place setting, it is used primarily for serving and eating liquid or semisolid food (sometimes called "spoon-meat"), and solid foods such as rice and cereal which cannot easily be lifted with a fork. Spoons are also used in food preparation to measure, mix, stir and toss ingredients. They can be made from metal (notably flat silver or silverware, plated or solid), wood or plastic. Abbreviation: sp. History. The earliest northern European spoon would seem to have been a chip or splinter of wood; Greek references point to the early and natural use of shells, such as those that are still used by primitive peoples. Ancient Indian texts also refer to the use of spoons. For example, the Rigveda refers to spoons during a passage describing the reflection of light as it "touches the spoon's mouth" (RV 8.43.10). Preserved examples of various forms of spoons used by the ancient Egyptians include those composed of ivory, flint, slate and wood; many of them carved with religious symbols. The spoons of the Greeks and Romans were chiefly made of bronze and silver and the handle usually takes the form of a spike or pointed stem. There are many examples in the British Museum from which the forms of the various types can be ascertained, the chief points of difference being found in the junction of the bowl with the handle. Middle Ages spoons at Chillon Castel Medieval spoons for domestic use were commonly made of cow horn or wood, but brass, pewter, and latten spoons appear to have been common in about the 15th century. The full descriptions and entries relating to silver spoons in the inventories of the royal and other households point to their special value and rarity. The earliest English reference appears to be in a will of 1259. In the wardrobe accounts of Edward I for the year 1300 some gold and silver spoons marked with the "fleur-de-lis", the Paris mark, are mentioned. One of the most interesting medieval spoons is the coronation spoon used in the anointing of the English sovereign. The sets of Apostle Spoons, popular as christening presents in Tudor times, the handles of which terminate in heads or busts of the apostles, are a special form to which antiquarian interest attaches. The earlier English spoon-handles terminate in an acorn, plain knob or a diamond; at the end of the 16th century, the baluster and seal ending becomes common, the bowl being fig-shaped. During The Restoration, the handle becomes broad and flat, the bowl is broad and oval and the termination is cut into the shape known as the hind's foot. In the first quarter of the 18th century, the bowl becomes narrow and elliptical, with a tongue or rat's tail down the back, and the handle is turned up at the end. The modern form, with the tip of the bowl narrower than the base and the rounded end of the handle turned down, came into use about 1760. Types and uses. Spoons are used primarily for eating liquid or semi-liquid foods, such as soup, stew or ice cream, and very small or powdery solid items which cannot be easily lifted with a fork, such as rice, sugar, cereals and green peas. In Southeast Asia, spoons are the primary utensil used for eating; forks are used only to push food onto the spoon. Spoons are also widely used in cooking and serving. In baking, batter is usually thin enough to pour or drop from a spoon; a mixture of such consistency is sometimes called "drop batter”. Rolled dough dropped from a spoon to a cookie sheet can be made into rock cakes and other cookies, while johnnycake may be prepared by dropping spoonfuls of cornmeal onto a hot greased griddle. A spoon is similarly useful in processing jelly, sugar and syrup. A test sample of jelly taken from a boiling mass may be allowed to slip from a spoon in a sheet, in a step called "sheeting". At the "crack" stage, syrup from boiling sugar may be dripped from a spoon, causing it to break with a snap when chilled. When boiled to 240°F. and poured from a spoon, sugar forms a filament, or "thread". Hot syrup is said to "pearl" when it forms such a long thread without breaking when dropped from a spoon. Used for stirring, a spoon is passed through a substance with a continued circular movement for the purpose of mixing, blending, dissolving, cooling, or preventing sticking of the ingredients. Mixed drinks may be "muddled" by working a spoon to crush and mix ingredients such as mint and sugar on the bottom of a glass or mixer. Spoons are employed for mixing certain kinds of powder into water to make a sweet or nutritious drink. A spoon may also be employed to toss ingredients by mixing them lightly until they are well coated with a dressing. A spoonful'"—the amount of material a spoon contains or can contain—is used as a standard unit of measure for volume in cooking, where it normally signifies a "'teaspoonful'". It is abbreviated "coch" or "cochl", from Latin "cochleare". "Teaspoonful" is often used in a similar way to describe the dosage for over the counter medicines. Dessert spoonful and tablespoonful may also be found in drink and food recipes. A teaspoon holds about 5ml and a tablespoon about 15ml. For storage, spoons and knives were sometimes placed in paired "knife boxes", which were often ornate wooden containers with sloping top, used especially during the 18th century. On the table, an ornamental utensil called a "nef", shaped like a ship, might hold a napkin, knife and spoon. The souvenir spoon generally exists solely as a decorative object commemorating an event, place, or special date. Spoons can also be used as a musical instrument. To "spoon-feed" oneself or another can simply mean to feed by means of a spoon. Metaphorically, however, it often means to present something to a person or group so thoroughly or wholeheartedly as to preclude the need of independent thought, initiative or self-reliance on the part of the recipient; or to present information in a slanted version, with the intent to preclude questioning or revision. Someone who accepts passively what has been offered in this way is said to have been spoon-fed. Manufacture. For machine-made spoons, the basic shape is cut out from a sheet of sterling silver, nickel silver alloy or stainless steel. The bowl is cross rolled between two pressurized rollers to produce a thinner section. The handle section is also rolled to produce the width needed for the top end. The blank is then cropped to the required shape, and two dies are used to apply the pattern to the blank. The fash is then removed using a lynisher, and the bowl is formed between two dies and bent. To make a spoon the traditional by way of handforging, a bar of silver is marked up to the correct proportions for the bowl and handle. It is then heated until red hot and held in tongs and using the hammer and anvil, beaten into shape. The tip of the bar is pointed to form the tip of the bowl, then hammered to form the bowl. If a heel is to be added, a section down the centre is left thicker. The edges of the bowl and the tip of the spoon are left thicker as this is where most of the thickness is needed. The handle is then started and hammered out to length going from thick at the neck and gradually tapering down in thickness giving a balanced feel. During this process the piece becomes very hard and has to be annealed several times, then worked again until the final shape is achieved. The bowl is filed to shape, often using a metal template. The bowl is then formed using a tin cake and spoon stake. The molten tin is poured around the spoon stake and left to harden. The handle is then bent down to 45 degrees, and the spoon is hammered into the tin using the spoon stake and a heavy hammer, to form the bowl. The bend in the handle is then adjusted to match the other spoons in the set and so it sits correctly on the table. The bowl is then filed level, a process called striking off. The surfaces are filed, first with a rough file to remove the fire stain from the surface, then with a smooth file. It is then buffed to remove any file marks and fire stain from inside the bowl and is polished to the desired finish. During the hand-forging process the spoon will have been hit with a hammer over 300 hundred times. A machine made spoon receives one or two blows from a press. Bibliography. Features broad array of collectible spoons from around the world, with values. Contains historical information and photos of antique collectible spoons.