Ares V

The Ares V is the cargo launching vehicle of the Constellation Program. It will replace the Space Shuttle when it is permanently phased out in 2010. At the beginning, the Ares V will launch the Earth Departure Stage and Altair lunar lander when NASA returns to the Moon, which is currently planned for 2019, but will also serve as the principle launcher for missions beyond the Earth-Moon system, including the program's ultimate goal, a manned mission to Mars after 2030. The unmanned Ares V will compliment the smaller, and man-rated Ares I rocket for the launching of the 3-4 person Orion spacecraft. Both rockets, deemed safer than the current Space Shuttle, will utilizing technologies developed for Project Apollo, the Shuttle, and the Delta IV EELV program.

The Ares V will be able to carry about 188 tonnes to Low Earth orbit, and 71 tonnes to the Moon. Upon completion the Ares V will be the most powerful rocket ever built, lifting more into orbit than even the American Saturn V, the failed Soviet N-1 for the cancelled Soviet Moonshot, and the successful Soviet/Russian Energia booster developed for the Buran Shuttle. The Ares V and the smaller Ares I are named after Ares, the Greek god of war, which is the equivalent to the Roman god Mars.

Ares I

The Ares I is the crew launching vehicle which is presently being developed by NASA as part of Constellation Program. NASA is planning to use Ares I to launch Orion spacecraft, which is being designed by NASA for human spaceflight missions after the Space Shuttle is retired in 2010. Ares I was previously known as the Crew Launch Vehicle or CLV. Ares I will complement the larger, unmanned Ares V, which is the cargo launch vehicle for Constellation. NASA selected the Ares designs for their anticipated overall safety, reliability and cost-effectiveness. Ares I and V are named after the Greek deity Ares, who is identified with the Roman god Mars.

The Constellation Program includes two separate launching vehicles: the Ares I, for the crew; and the Ares V, for cargo. Having two separate launching vehicles will allow for more specialized designs for the different purposes the rockets will fulfill.

The Ares I rocket is specifically being designed to boost the Orion Crew spacecraft. Orion is intended as a crew capsule, similar in design to the Project Apollo capsule, to transport astronauts to the International Space Station, the Moon, and perhaps Mars. The first stage of the Ares I is a more powerful and reusable solid fuel rocket derived from the current Space Shuttle Solid Rocket Booster. This fifth segment will enable the Ares I to produce more thrust and burn longer. Other changes made to the solid rocket booster are the removal of the Space Shuttle External Tank attachment points and the replacement of the solid rocket booster nosecone with a new forward adapter that will interface with the liquid-fueled second stage. The adapter will be equipped with solid-fueled separation motors to facilitate the disconnection of the stages during ascent.

The upper stage is to be propelled by one J-2X rocket engine fueled by liquid hydrogen (LH2) and liquid oxygen (LOX). The J-2X is derived from the J-2 engine used on the Saturn IB and Saturn V rockets. On July 16, 2007, NASA awarded Rocketdyne a sole-source contract for the J-2X engines to be used for ground and flight tests. Although its J-2X engine is derived from an established design, the upper stage itself is wholly new. Originally based on the internal structure of the Shuttle's External Tank, the original design called for separate fuel and oxidizer tanks, separated by an "intertank" structure. Using a concept going back to the Apollo era, the "intertank" structure was dropped to decrease mass, and instead, a common bulkhead would be used between the tanks.

The upper stage of Ares I is to be built at the NASA Michoud Assembly Facility, the current location of the fabrication and construction of the Shuttle's External Tank, and the former construction site of the Saturn V's first stage, the S-IC.

Orion Spacecraft

Orion is a spacecraft design which is under development by NASA. Each Orion spacecraft will carry a crew of four to six astronauts. This new NASA spaceship will be launched by the Ares I, which is a launching booster also under development. Both Orion and Ares I are parts of NASA's Constellation Program, a space project to send human explorers to the Moon by 2020, and then onward to Mars and perhaps other destinations in the Solar System. On August 31, 2006, Lockheed Martin was granted the contract by NASA to design, develop, and build Orion.

Orion spacecraft will be launched from Launch Complex 39 at Kennedy Space Center, the same launch complex that currently launches the space shuttle. While shuttle operations continue from launch pad 39A, 39B is being readied for Ares launches. NASA will use Orion spacecraft for its human spaceflight missions after the last shuttle orbiter is retired in 2010. The first crewed Orion flight is anticipated in 2015. Subsequent flights will visit the International Space Station. If commercial orbital transportation services are unavailable, Orion will handle logistic flights to the Station. After that, Orion is to become a key component of human missions to the Moon and Mars.

On January 14, 2004, President George W. Bush announced the Orion spacecraft, known then as the Crew Exploration Vehicle, as part of the Vision for Space Exploration. The proposal to create the Orion spacecraft was partly a reaction to the Space Shuttle Columbia accident, the subsequent findings and report by the Columbia Accident Investigation Board (CAIB), and the White House's review of the American space program. The Orion spacecraft effectively replaced the conceptual Orbital Space Plane (OSP), which itself was proposed after the failure of the Lockheed Martin X-33 program to produce a replacement for the space shuttle.

The Crew and Service Module stack of the Orion spacecraft is composed of two main parts: a conical Crew Module, and a cylindrical Service Module that holds the spacecraft's propulsion system and expendable supplies. Both are based substantially on the Apollo Command and Service Modules (Apollo CSM) flown between 1967 and 1975, but include advances derived from the space shuttle program. "Going with known technology and known solutions lowers the risk," according to Neil Woodward, director of the integration office in the Exploration Systems Mission Directorate.

Orion Spacecraft

Constellation Program

The Constellation Program is a human spaceflight program planned by NASA. The stated goals of the program are gaining significant experience in operating away from Earth's environment, developing technologies needed for opening the space frontier and conducting fundamental science. Constellation was developed through the Exploration Systems Architecture Study, which determined how NASA would pursue the goals laid out in the Vision for Space Exploration and the NASA Authorization Act of 2005.

As part of the Constellation program, NASA plans to develop spacecraft and booster vehicles to replace the Space Shuttle and send astronauts to the Moon and possibly to Mars as well. Currently, NASA is in the process of designing two boosters, the Ares I and Ares V. Ares I will have the sole function of launching mission crews into orbit. Ares V will be designed to launch other hardware for use on missions and will have a heavier lift capacity than the Ares I booster. In addition to these two boosters, NASA is designing a set of other spacecraft for use during Constellation. These will include the Orion crew capsule, the Earth Departure Stage and the Altair lunar lander. Concerned by price increases on the program, U.S. President Obama has ordered a review of the project that will report by August 2009.

A full-scale mockup of NASA's Orion crew module is being tested in water under simulated and real landing weather conditions. Beginning March 23, a Navy-built, 18,000-pound Orion mockup will be placed in a test pool at the Naval Surface Warfare Center's Carderock Division in West Bethesda, Md. Ocean testing will begin April 6 off the coast of NASA's Kennedy Space Center in Florida.

The goal of the operation, dubbed the Post-landing Orion Recovery Test, or PORT, is to determine what kind of motions the astronaut crew can expect after landing, as well as conditions outside for the recovery team. The experience will help NASA design landing recovery operations including equipment, ship and crew necessities.

The Carderock facility provides a controlled environment for crew recovery personnel to familiarize themselves with the Orion capsule before the team tests procedures in the uncontrolled waters of the Atlantic Ocean.

For the ocean testing, the team will use a space shuttle solid rocket booster recovery ship to take the mockup out to sea, going further into rougher conditions each day. A media opportunity to view testing visible from shore will be scheduled for April 7 at Kennedy.

During the Orion mockup's transportation from Maryland to Florida, it will make stops for public viewing. Designated opportunities are March 30 in front of the Smithsonian National Air and Space Museum in Washington and April 3 at the Kennedy Space Center Visitor's Complex in Florida.

NASA's Constellation Program, which includes the Orion crew vehicle and the Ares I rocket that will launch it, is America's next-generation human spaceflight system that will carry astronauts to the International Space Station, back to the moon and to destinations beyond.

The Constellation Program's Operations and Test Integration Office at NASA's Johnson Space Center in Houston is leading the PORT effort. Development of Orion and associated Constellation Program elements is a joint effort involving every NASA center and partners across the country. Results of these tests will influence Orion vehicle design at Johnson and recovery hardware designs under evaluation at Kennedy.

NASA`s Constellation Program

New Fuel Source

Nuclear waste could be the new fuel source. There is a tantalizing amount of energy in all that nuclear waste that was slated to sit in Yucca Mountain for eons. Now that it won't be sitting there, some think it should be used. All of the electricity used by a typical American in a year can be generated by just three inches of one of the 14-foot rods of uranium dioxide used to power nuclear reactors. Yet when that rod, which has the diameter of a Bic pen, is "spent" and set aside as nuclear waste, less than 10% of the energy in the rod has been turned into electricity.

"Waste is just too gross of a term for it," says Sherrell Greene, director of Nuclear Technology at Oak Ridge National Laboratory. "I'm trying to get to the 90% of the fuel in that rod."

It's a difficult thing to do, but these days there's much more incentive to try. This spring the Obama administration effectively ended the long-tortured idea of storing the nation's spent nuclear fuel deep under Yucca Mountain in south-central Nevada. At the same time, the nation seems to be inching toward adding new nuclear reactors, creating more waste that we don't know what to do with. (When Yucca Mountain was conceived, it was assumed that the nuclear reactors in the United States would be shut down as they aged and not replaced.)

There is already a method used by countries like France and Japan to reprocess spent nuclear fuel. It has a long list of nasty problems associated with it, however. It's very expensive--the cost of uranium would have to jump by a factor of six to match the price of reprocessed fuel. Though reprocessing nuclear fuel shrinks the amount of waste, it doesn't eliminate it. And, worst of all, it results in the creation of plutonium, which could be used to make nuclear weapons.

For all of these reasons, the U.S., which invented the process as part of its nuclear weapons program in the 1940s and 1950s then pushed it as a recycling method up until the early 1970s, never built a reprocessing plant and has strongly discouraged other nations from doing so.

But the politics of reprocessing have been heating up. Pro-nuclear energy Sens. John McCain, R-Ariz., and Lamar Alexander, R-Tenn., pushed Energy Secretary Steven Chu on the issue in the spring. McCain and others suggest one big reason new nuclear reactors are not being built is the uncertainty around where the spent fuel is going to go.

In June, the House Science and Technology Committee held a hearing asking experts for suggestions about how reprocessing should be approached. Mark Peters, of Argonne National Laboratory, said that because the U.S. never invested in a big, current-generation reprocessing plant, the country has the opportunity to instead design and build a safer system.

The hope is that researchers can develop a method that extracts the usable portion of the spent fuel without isolating the plutonium. Left behind would be very poisonous nuclear waste, but waste that would degrade in tens of years instead of tens of thousands of years, making the need for very long-term storage less acute.

(When nuclear waste includes extremely radioactive elements, it is said to be "self-protecting"--the gamma rays that it emits would cook a person so fast that it's all but impossible to do something nefarious with it. Plutonium on its own, while very dangerous if inhaled, emits comparatively weak alpha radiation, which can be easily shielded.)

At Oak Ridge, Greene's team last year demonstrated a method by which it removed the uranium and the plutonium together. The team processed just 45 pounds of material, and Greene admits that they are far from proving it can be done on an industrial scale. "But it is now an established fact that we know a new set of processes to produce a new fuel without having to produce plutonium," he says. "It may very well be that it doesn't end up being the best method, but if there is one set of processes to do it, there are others. I'm confident we can find a way to do this."

Argonne National Laboratory has developed a method called pyroprocessing that uses molten salt to separate the materials instead of a water-based approach, like the methods used abroad and at Oak Ridge. Some so-called Generation IV nuclear reactors being researched eliminate the need for reprocessing or include pyroprocessing. And some suggest using nuclear fission to help transform nuclear waste into fuel. (See "Reinventing Nuclear Power.")

Many, though, are adamantly opposed to reprocessing. They argue that though some methods, new and old, do reduce the volume of waste, they actually complicate waste disposal by creating different types of radioactive waste. They also remain extraordinarily expensive. And while methods like the one being explored at Oak Ridge do protect the plutonium slightly, it's not nearly enough to eliminate the threat of proliferation.

"It's an oxymoron to talk about proliferation-resistant reprocessing," says Frank von Hippel, a physicist and professor of public and international affairs at Princeton University's Woodrow Wilson School. "Nobody has a good idea at the moment."

Another critic: John Holdren, Obama's science adviser, who argued against nuclear reprocessing in a 2003 paper.

In the meantime, nuclear waste in the U.S. is being stored at nuclear plants. The spent rods are cooled in pools of water for at least a year and then transferred to thick casks of steel and concrete.

No one seems to think this method is ideal, but both proponents and opponents of reprocessing agree that the method is acceptable for the next few decades. Which may give us time to either come up with better reactors or better reprocessing technologies.

"The vision in this country is that as long as we have nukes, we have an assumption that there will always be nuclear waste so we should learn to deal with it," says Oak Ridge's Greene. "Well, maybe there are other nuclear fuel cycles and reactors and processes that can minimize creation of problem."

(Source: www.forbes.com )

Hypophysis

The hypophysis, also called pituitary gland, is an endocrine gland about the size of a pea. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in the sella turcica ( a small, bony cavity) covered by a dural fold (diaphragma sellae). The hypophysis produces hormones that regulate homeostasis, and stimulate other endocrine glands. It is functionally connected to the hypothalamus by the median eminence.

The hypophysis is situated at the base of the brain and is connected to the hypothalamus by the pituitary stalk. hypothalamic releasing factors stimulate the release of pituitary hormones. It consists of two lobes: 1) the adenohypophysis, or the anterior pituitary; 2) the neurohypophysis, or the posterior pituitary. Both of its lobes are under the control of the hypothalamus.

The adenohypophysis secretes important endocrine hormones, such as adrenocorticotropic hormone , Thyroid-stimulating hormone, PRL, GH, endorphins, FSH, and LH. These hormones are released from the anterior pituitary under the influence of the hypothalamus. Hypothalamic hormones are secreted to the anterior lobe by way of a special capillary system, called the hypothalamic-hypophyseal portal system.

The neurohypophysis stores and releases oxytocin, most of which is released from the paraventricular nucleus in the hypothalamus, and vasopressin and AVP, arginine vasopressin, the majority of which is released from the supraoptic nucleus in the hypothalamus.

The hypophysis hormones help control some of the following body processes: growth, blood pressure, breast milk production, sex organs, thyroid gland, metabolism, etc.

Fornix (Brain)

The fornix is an arch-shaped bundle of axons in the cerebrum. It is located below the corpus callosum and separated from it in front by the the septum pallucidum. It transmits signals from the hippocampus to the mammillary bodies and septal nuclei. The fornix begins in the hippocampus on each side of the brain. The left and right sides are each called the crux of the fornix. The bundle of axons come together in the midline of the brain and form the body of the fornix. The body of the fornix travels backward to divide again near the anterior commissure.

Mammillary Bodies

The mammillary bodies are a pair of spherical masses of gray matter at the base of the brain, located between the hypophysis and oculomotor nerve that receives and relays olfactory impulses. Being part of the limbic system, the mammillary bodies are situated at the ends of the anterior arches of the fornix, and are composed of two groups of nuclei, the medial mammillary nuclei and the lateral mammillary nuclei. The mammillary bodies function as a relay for impulses coming from the amygdalae and hippocampi, via the mamillo-thalamic tract to the thalamus. This circuit, from amygdalae to mamillary bodies, and then on to the thalamus, is part of the larger Papez circuit.

Tuber Cinereum

The tuber cinereum is a hollow eminence of gray matter located between the optic chiasma in front and the mammilary bodies. It forms part of the floor of the third ventricle. Laterally the tuber cinereum is continuous with the anterior perforated substances and anteriorly with a thin lamina, the lamina terminalis. From the under surface of the tuber cinereum a hollow conical process, the infundibulum, projects downward and forward and is attached to the posterior lobe of the hypophysis. The infundibulum, which is a hollow conical process, projects from the tuber cinereum. The infundibulum extends forward and down where it is attached to the posterior lobe of the pituitary gland.

Corpus Callosum

The corpus callosum is a broad, thick bundle of axons which runs sideways connecting the two cerebral hemispheres. It is a white matter structure beneath the cerebral cortex. The corpus callosum is composed of 250 million contralateral axonal projections. The posterior portion of the corpus callosum is called the splenium; the anterior is called the genu; between the two is the body. The rostrum is the portion of the corpus callosum that projects posteriorly following from the anteriormost genu.

Basilar Sulcus

The basilar sulcus is a median fissure on the ventral surface of the pons varolii in which lies the basilar artery. The basilar sulcus is bounded on either side by an eminence caused by the descent of the cerebrospinal fibers through the substance of the pons.

Cingulate Sulcus

The cingulate sulcus is a fissure on the medial wall of the cerebral hemisphere. It bounds the upper surface of the cingulate gyrus and borders the paracentral lobule posteriorly. The anterior portion of the cingulate sulcus is called the pars subfrontalis. The posterior portion which curves up to the superomedial margin of the hemisphere and borders the paracentral lobule posteriorly, the pars marginalis.

Cingulate Sulcus

Cingulate Gyrus

Cingulate gyrus is located in the medial part of the cerebrum, limited above by the cingulate sulcus, partially wrapping around the corpus callosum. It is a long curved gyrus of the medial surface of the cortical hemisphere, bending over the corpus callosum from which it is separated by the deep sulcus of the corpus callosum. The cortical part of the cingulate gyrus is referred to as cingulate cortex.

As it gets inputs from the anterior nucleus of the thalamus and the neocortex, as well as from somatosensory areas of the cerebral cortex, the cingulate gyrus functions as an integral part of the limbic system, which is involved with emotion formation and processing, learning, and memory.

Cerebellum

The cerebellum is an organ of the central nervous system. It is situated just below the posterior part of the cerebrum. The cerebellum plays a key role in coordination and motor control. There are many neural pathways linking the cerebellum with the cerebral motor cortex, that sends information to the muscles causing them to move and the spinocerebellar tract, providing feedback on the position of the body in space.

Lesions in the cerebellum result in disorders in fine movement, equilibrium, posture, and motor learning. Since the 18th century, physiologists have indicated that patients with cerebellar damage show problems with motor coordination and movement. Research into cerebellar function during the early to mid 19th century was done via lesion and ablation studies in animals. Research physiologists noted that such lesions led to animals with strange movements, awkward gait, and muscular weakness. These observations and studies led to the conclusion that the cerebellum was a motor control structure. Nevertheless, modern research shows that the cerebellum has a broader role in a number of key cognitive functions, including attention and the processing of language, music, and other sensory temporal stimuli.

The human cerebellum changes with age. These changes may be different from those of other parts of the brain, e.g., the gene expression pattern in the human cerebellum shows less age-related alteration than in the human cerebral cortex.A stereological study has found that human cerebellar white matter is reduced by 26% with age.

Spinal Cord

The spinal cord is a long, nearly cylindrical bundle of nervous tissue which is part of the Central Nervous System and continuous with the medulla oblongata. The spinal cord is composed of myelinated axons which extend from the cerebral cortex, forming its external white matter, and neurons bodies that are clustered together in the center in an H-like pattern of grey matter. Encapsulated in the vertebral column, the spinal cord has two functions: it transmits nervous signals between the brain and the rest of the body and independently controls numerous reflexes and central pattern generators.

The spinal cord is 45 cm long in men and 43 cm long in women, is enlarged in the cervical and lumbar regions. The spinal cord white matter envelops the grey matter, which has an H-like appearance. The spinal cord is divided into 31 segments as 31 pairs of spinal nerves (right and left pairs) branch out of each segment. Each nerve has a ventral (anterior), and a dorsal (posterior) root; the latter can be distinguished by the presence of an oval swelling, the spinal ganglion, which contains numerous nerve cells. 6–8 motor nerve rootlets spring from right and left ventro lateral sulci in an orderly manner. Nerve rootlets get together to form nerve roots. Likewise sensory nerve rootlets form off right and left dorsal lateral sulci and form sensory nerve roots. The ventral (motor) and dorsal (sensory) roots combine to form spinal nerves(mixed; motor and sensory), one on each side of the spinal cord.

The spinal cord is divided into cervical, thoracic, lumbar and sacral regions, corresponding with the attachments of the different groups of nerves. There are 8 pairs of cervical spinal nerves, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal.

Somatosensory System

The somatosensory system is a sensory system which comprises the receptors and processing center in the cerebral cortex. It produces the sensory modalities such as touch, temperature, proprioception (body position), and nociception (pain). The sensory receptors cover the skin and epithelia, skeletal muscles, bones and joints, internal organs, and the cardiovascular system.

The processing center of the somatosensory system is situated just posterior to the central sulcus in the lateral postcentral gyrus of the parietal lobe of the cerebral cortex. The somatosensory system is involved in processing tactile information (sense of touch) and it receives the somatic sensory data from the ventrobasal nucleus of the thalamus.

Superior Temporal Gyrus

The superior temporal gyrus is situated in the upper part of the temporal lobe and is one of three gyri which the temporal lobe contains. The superior temporal gyrus is bounded above by the lateral sulcus; below, by the superior temporal sulcus, which is not always present or visible; and by an imaginary line drawn from the preoccipital notch to the lateral sulcus posteriorly.

The superior temporal gyrus contains the Wernicke's area (speech comprehension center) in its posterior part. The primary auditory cortex is also located in the superior temporal gyrus. This gyrus is associated with developmental mechanisms of brain lateralization and the pathogenesis of language-related schizophrenic symptoms. The predominantly right-sided volumetric abnormalities found in the superior temporal gyrus may reflect a particularly early neurodevelopmental disruption in patients with early-onset schizophrenia.

Language Centers in the Brain

The language centers in the brain are represented by Broca's area and Wernicke's area. These areas function as speech processing and production centers. The language centers are located in most people in the left cerebral hemisphere: the Broca's area in the inferior frontal gyrus of the frontal lobe, and the Wernicke's area in the superior temporal gyrus of the temporal lobe.

Although they are situated in different lobes of the cerebral cortex, the two language centers are closely interconnected via axons which runs from the temporal to the frontal lobe and vice versa. The Broca's area is a speech production center with motor functions; the Wernicke's area is a language comprehension center, which is next to the primary auditory cortex.

Language Centers

Encephalon

The encephalon is the part of the central nervous system which is inclosed in the cranium and is continuous with the spinal cord. The encephalon is composed of the cerebral cortex, basal ganglia, hippocampus, thalamus, hypothalamus, cerebral peduncles, cerebelum, and brainstem (midbrain, pons, medulla). The encephalon is wrapped up by the meninges, which is the system of membranes, enveloping the central nervous system.

Pars Opercularis

The pars opercularis is situated in the inferior frontal gyrus of the frontal lobe, lying between the inferior precentral sulcus, the ascending ramus of the lateral sulcus, and the lateral sulcus. Thus, it occupies the posterior part of the inferior frontal gyrus. It is called opercularis because it covers part of the insula. The pars opercularis and the pars triangularis make up Broca's area. It has been postulated that abnormal blood flow in the Pars opercularis is an indicator for autism.

Electrical stimulation or damage to the pars opercularis interferes with language production. There is considerable variability in the shape and location of the pars opercularis across brains and between cerebral hemispheres, and there is no significant difference or correlation between left and right hemisphere grey matter volumes. There is also no significant difference between sex and side of asymmetry of the pars opercularis.

Pars Triangularis

Pars triangularis is a small region in the left inferior frontal gyrus of the frontal lobe. The pars triangularis is bounded above by the inferior frontal sulcus, and below by the anterior horizontal ramus, with the anterior ascending ramus forming its caudal boundary. The pars triangularis along with the rest of the inferior frontal gyrus and the pars opercularis make up Broca's area, which is involved in language production. It has been found leftward asymmetries, that is to say larger pars triangularis region in the left hemisphere than the same region in the right hemisphere of the pars triangularis, especially in right-handed individuals and rightward asymmetries in left-handed subjects.

Pars Triangularis

Inferior Frontal Gyrus

The inferior frontal gyrus is a gyrus situated in the frontal lobe of the cerebrum. It lies between the middle frontal gyrus and the precentral frontal gyrus. The inferior frontal gyrus limited by the inferior frontal sulcus and the inferior border the lateral sulcus, and the inferior precentral sulcus. The Broca´s area, the speech pruduction center, is located in the inferior frontal gyrus.

The inferior frontal gyrus is subdivided into the following macroanatomical structures: 1) Pars opercularis (cortex posterior to the ascending ramus of the lateral fissure); 2) Pars triangularis (cortex between the ascending ramus and the horizontal ramus of the lateral fissure); Pars orbitalis (cortex inferior and anterior to the horizontal ramus of the lateral fissure).

Wernicke´s Area

The Wernicke's area is situated in the posterior section of the superior temporal gyrus, in the temporal lobe of the left cerebral hemisphere. It encircles the primary auditory cortex on the Sylvian fissure. The Wernicke´s area is neuroanatomically described as the posterior part of Brodmann area 22. Wernicke's area is connected to Broca's area via the arcuate fasciculus, a neural pathway, and to the visual cortex via the angular gyrus. Wernicke’s area is involved with speech comprehension.

Wernicke's area was named after Carl Wernicke, a German neurologist and psychiatrist. He hypothesized a link between the left posterior section of the superior temporal gyrus and the reflexive mimicking of words and their syllables that associated the sensory and motor images of spoken words. Damage to the Wernicke´s area results in speech understanding impairment, or Wernicke´s Aphasia.

The recognition of a word takes place in the Wernicke´s area, using neurons in the posterior and middle portion of the superior temporal gyrus. Comprehension of a word is a complex process of analyzing the acoustic, phonological, lexical, and syntactic level of a word. Wernicke's area puts meaning onto words, and pairs words with meanings.

Broca´s Area

Broca's area is a region of the cerebral cortex that is responsible for speech production. The Broca's area was named after the French Physician Paul Pierre Broca, who discovered that this area of the cerebrum is specilized in speech production. The deficit in language production as a result of damage to this region is called Broca’s aphasia. Broca’s area is now typically defined in terms of the pars opercularis and pars triangularis of the inferior frontal gyrus, represented in Brodmann’s cytoarchitectonic map as areas 44 and 45. Studies of chronic aphasia led to the realization of the essential role of Broca’s area in various speech and language functions.

Broca’s area in the left hemisphere and its homologue in the right hemisphere receive more afferent connections from prefrontal cortex, the superior temporal gyrus, and the superior temporal sulcus. It is connected to the Wernicke’s area of the brain by the arcuate fasciculus, which is a pathway made of neurons. Broca´s area is made up of two primary parts: the Pars triangularis and the Pars opercularis. The Pars triangularis is situated in the anterior portion of Broca's area, while the Pars opercularis is located in the posterior region of Broca's area.