ratio of word probabilities predicted from brain for hand and desk

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hand

desk

top 10 words in brain distribution (in article):
form body muscle head human bone brain tissue animal allow
top 10 words in brain distribution (in article):
build wood store design wall structure type size home form
top 10 words in brain distribution (not in article):
cell fuel engine energy gas produce iron power blade wear
top 10 words in brain distribution (not in article):
city material house street floor paint town state construction Unite
times more probable under hand 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under desk
(words not in the model)
The hands'" (med. /lat.: manus, pl. manūs) are the two intricate, prehensile, multi-fingered body parts normally located at the end of each arm of a human or other primate. They are the chief organs for physically manipulating the environment, using anywhere from the roughest motor skills (wielding a club) to the finest (threading a needle), and since the fingertips contain some of the densest areas of nerve endings on the human body, they are also the richest source of tactile feedback so that sense of touch is intimately associated with human hands. Like other paired organs (eyes, ears, legs), each hand is dominantly controlled by the opposing brain hemisphere, and thus handedness, or preferred hand choice for single-handed activities such as writing with a pen, reflects a significant individual trait. What constitutes a hand? Many mammals and other animals have grasping appendages similar in form to a hand such as paws, claws, and talons, but these are not scientifically considered to be hands. The scientific use of the term "hand" to distinguish the terminations of the front paws from the hind ones is an example of anthropomorphism. The only true hands appear in the mammalian order of primates. Hands must also have opposable thumbs, as described later in the text. Humans have only two hands (except in cases of polymelia), which are attached to the arms. Apes and monkeys are sometimes described as having four hands, because the toes are long and the hallux is opposable and looks more like a thumb, thus enabling the feet to be used as hands. Also, some apes have toes that are longer than human fingers. Anatomy of the human hand. The human hand consists of a broad palm (metacarpus) with 5 digits, attached to the forearm by a joint called the wrist (carpus). The back of the hand is formally called the dorsum of the hand. Digits. The four fingers on the hand are used for the outermost performance; these four digits can be folded over the palm which allows the grasping of objects. Each finger, starting with the one closest to the thumb, has a colloquial name to distinguish it from the others: The thumb (connected to the trapezium) is located on one of the sides, parallel to the arm. The thumb can be easily rotated 90°, on a level perpendicular to the palm, unlike the other fingers which can only be rotated approximately 45°. A reliable way of identifying true hands is from the presence of opposable thumbs. Opposable thumbs are identified by the ability to be brought opposite to the fingers, a muscle action known as opposition. Bones. The human hand has 27 bones: the carpus or wrist account for 8; the metacarpus or palm contains 5; the remaining 14 are digital bones; fingers and thumb. The eight bones of the wrist are arranged in two rows of four. These bones fit into a shallow socket formed by the bones of the forearm. The bones of proximal row are (from lateral to medial): scaphoid, lunate, triquetral and pisiform. The bones of the distal row are (from lateral to medial): trapezium, trapezoid, capitate and hamate. The palm has 5 bones (metacarpals), one to each of the 5 digits. These metacarpals have a head and a shaft. Human hands contain 14 digital bones, also called phalanges, or phalanx bones: 2 in the thumb (the thumb has no middle phalanx) and 3 in each of the four fingers. These are: Sesamoid bones are small ossified nodes embedded in the tendons to provide extra leverage and reduce pressure on the underlying tissue. Many exist around the palm at the bases of the digits; the exact number varies between different people. Articulations=== Also of note is that the articulation of the human hand is more complex and delicate than that of comparable organs in any other animals. Without this extra articulation, we would not be able to operate a wide variety of tools and devices. The hand can also form a fist, for example in combat, or as a gesture. Muscles and tendons. The movements of the human hand are accomplished by two sets of each of these tissues. They can be subdivided into two groups: the extrinsic and intrinsic muscle groups. The extrinsic muscle groups are the long flexors and extensors. They are called extrinsic because the muscle belly is located on the forearm. The intrinsic muscle groups are the thenar and hypothenar muscles (thenar referring to the thumb, hypothenar to the small finger), the interosseus muscles (between the metacarpal bones, four dorsally and three volarly) and the lumbrical muscles. These muscles arise from the deep flexor (and are special because they have no bony origin) and insert on the dorsal extensor hood mechanism. The fingers have two long flexors, located on the underside of the forearm. They insert by tendons to the phalanges of the fingers. The deep flexor attaches to the distal phalanx, and the superficial flexor attaches to the middle phalanx. The flexors allow for the actual bending of the fingers. The thumb has one long flexor and a short flexor in the thenar muscle group. The human thumb also has other muscles in the thenar group (opponens- and abductor muscle), moving the thumb in opposition, making grasping possible. The extensors are located on the back of the forearm and are connected in a more complex way than the flexors to the dorsum of the fingers. The tendons unite with the interosseous and lumbrical muscles to form the extensorhood mechanism. The primary function of the extensors is to straighten out the digits. The thumb has two extensors in the forearm; the tendons of these form the anatomical snuff box. Also, the index finger and the little finger have an extra extensor, used for instance for pointing. The extensors are situated within 6 separate compartments. The 1st compartment contains abductor pollicis longus and extensor pollicis brevis. The 2nd compartment contains extensors carpi radialis longus and brevis. The 3rd compartment contains extensor pollicis longus. The extensor digitorum indicis and extensor digititorum communis are within the 4th compartment. Extensor digiti minimi is in the fifth, and extensor carpi ulnaris is in the 6th. Variation. Some people have more than the usual number of fingers or toes, a condition called polydactyly. Others may have more than the typical number of metacarpal bones, a condition often caused by genetic disorders like Catel-Manzke syndrome. The average length of an adult male hand is 189 mm, while the average length of an adult female hand is 172 mm. The average hand breadth for adult males and females is 84 and 74 mm respectively. A desk'" is a furniture form and a class of table often used in a work or office setting for reading or writing on or using a computer. Desks often have one or more drawers to store office supplies and papers. Unlike a regular table, usually only one side of a desk is suitable to sit on (though there are some unusual exceptions, such as a partners desk). Not all desks have the form of a table. For instance, an Armoire desk is a desk built within a large wardrobe-like cabinet, and a portable desk is light enough to be placed on a person's lap. Early desks. Desk-style furniture appears not to have been used in classical antiquity or in other ancient centers of civilization in the Middle East or Far East, but there is no specific proof. Medieval illustrations show the first pieces of furniture which seem to have been designed and constructed for reading and writing. Before the invention of the movable type printing press in the 15th century, any reader was potentially a writer or publisher or both, since any book or other document had to be copied by hand. The desks were designed with slots and hooks for bookmarks and for writing implements. Since manuscript volumes were sometimes large, and heavy, desks of the period usually had massive structures. Desks of the Renaissance and later eras had relatively slimmer structures, and more and more drawers as woodworking became more precise and cabinet-making became a distinct trade. It is often possible to find out if a table or other piece of furniture of those times was designed to be used as a desk by looking for a drawer with three small separations (one each for the ink pot, the blotter and the powder tray) and room for the pens. The desk forms we are familiar with in this beginning of the millennium were born mostly in the 17th and 18th centuries. The ergonomic desk of the last decades is the newest addition to a long list of desk forms, but in a way it is only a refinement of the mechanically complex drawing table or drafting table of the end of the 18th century. Industrial era. Refinements to those first desk forms were considerable through the 19th century, as steam-driven machinery made cheap wood-based paper possible in the last periods of the first phase of the industrial revolution. This produced a boom in the number of, or some might say the birth of, the white-collar worker. As these office workers grew in number, desks were mass-produced for them in large quantities, using newer, steam-driven woodworking machinery. This was the first sharp division in desk manufacturing. From then on, limited quantities of finely crafted desks have been constructed by master cabinetmakers for the homes and offices of the rich while the vast majority of desks were assembled rapidly by unskilled labor, from components turned out in batches by machine tools. Thus, age alone does not guarantee that an antique desk is a masterpiece, since this shift took place more than a hundred years ago. More paper and more correspondence drove the need for more complex desks and more specialized desks, such as the rolltop desk which was a mass produced, slatted variant of the classical cylinder desk. It provided a relatively fast and cheap way to lock up the ever increasing flow of paper without having to file everything by the end of the day. Paper documents started leaving the desk as a "home," with the general introduction of filing cabinets. Correspondence and other documents were now too numerous to get enough attention to be rolled up or folded again, then summarized and tagged before being pigeonholed in a small compartment over or under the work surface of the desk. The famous Wooton desk and others were the last manifestations of the "pigeonhole" style. The newer desks could be transformed into many different shapes and angles and were ideal for artists. Steel desks. A smaller boom in office work and desk production occurred at the end of the 19th century and the beginning of the 20th with the introduction of smaller and cheaper electrical presses and efficient carbon papers coupled with the general acceptance of the typewriter. Steel desks were introduced to take heavier loads of paper and withstand the pounding meted out on the typewriters. The L-shaped desk became popular, with the "leg" being used as an annex for the typewriter. Another big boom occurred after the Second World War with the spread of photocopying. Paperwork drove even higher the number of desk workers, whose work surface diminished in size as office rents rose, and the paper itself was moved more and more directly to filing cabinets or sent to records management centers, or transformed into microfilm, or both. Modular desks seating several co-workers close by became common. Even executive or management desks became mass-produced, built of cheap plywood or fiberboard covered with wood veneer, as the number of persons managing the white collar workers became even greater. Student desks. A "'student desk'" can be any desk form meant for use by a student. Usually the term designates a small pedestal desk or writing table constructed for use by a teenager or a pre-teen in his or her room at home. More often than not it is a pedestal desk, with only one of the two pedestals and about two thirds of the desk surface. Such desks are sometimes called left pedestal desks or right pedestal desks depending on the position of the single pedestal. The height of the desk is usually a bit lower than is the case for normal adult desks. In some cases, the desk is connected from the seat to the table. The table is also used for sitting before classes. The desks are usually mass-produced in steel or wood and sold on the consumer market. In addition there is a wide variety of plans available for woodworking enthusiasts. There are many novel forms of student desks made to maximize the relatively restricted area available in a child's room. One of the most common is the bunk bed desk, also known as a loft bed. Impact of computers. Until the late 1980s desks remained a place for paperwork and business negotiation. At the end of this decade though the personal computer was taking hold in large and medium sized businesses. New office suites included a "knee hole" credenza which was a place for a terminal or personal computer and keyboard tray. Soon new office designs also included "U-shape" suites which added a bridge worksurface between the back credenza and front desk. During the North American recession of the early 1990s, many manager and executive workers had to do word processing and other functions previously completed by typing pools and secretaries. This necessitated a more central placement of the computer on these "U-shape" suite desk systems. With computers abounding, "computer paper" became an office staple. The beginning of this paper boom gave birth to the dream of the "paperless office", in which all information would appear on computer monitors. However, the ease of printing personal documents and the lack of comfort with reading text on computer monitors led to a great deal of document printing. The need for paperwork space vied with the rising desk space taken up by computer monitors, CPUs, printers, scanners, and other peripherals. As well, the need for more space led some desk companies to attach some items to the modesty panel at the back of the desk, such as multi-outlets and cabling. Through the "tech boom" of the 1990s, office worker numbers skyrocketed along with the cost of office space rent. The cubicle desk became widely accepted in North America as an economical way of putting more desk workers in the same space without actually shrinking the size of their working surfaces. The cubicle walls have become new place for workers to affix papers and other items once left on the horizontal desktop surface. Even computer monitor frames themselves are used to attach reminder notes and business cards. Early in the 2000s, private office workers found that their side and back computer-placing furniture made it hard to show the contents of a computer screen to guests or co-workers. Manufacturers have responded to this issue by creating "Forward Facing" desks where computer monitors are placed on the front of the "U-shape" workstation. This forward computer monitor placement promotes a clearer sight-line to greet colleagues, increases computer screen privacy and allows for common viewing of information displayed on a screen. References. Articles and books on real and virtual desks and things in between: