The ear is an organ of the body that is used for hearing and balance. It is connected to the brain by the auditory nerve and is composed of three divisions, the external ear, the middle ear, and the inner ear. The greater part of which is enclosed within the temporal bone.
The ear is looked upon as a miniature receiver, amplifier and signal-processing system. The structure of the outer ear catching sound waves as they move into the external auditory canal. The sound waves then hit the eardrum and the pressure of the air causes the drum to vibrate back and forth. When the eardrum vibrates its neighbour the malleus then vibrates too. The vibrations are then transmitted from the malleus to the incus and then to the stapes. Together the three bones increase the pressure which in turn pushes the membrane of the oval window in and out. This movement sets up fluid pressure waves in the perilymph of the cochlea. The bulging of the oval window then pushes on the perilymph of the scala vestibuli. From here the pressure waves are transmitted from the scala vestibuli to the scala tympani and then eventually finds its way to the round window. This causes the round window to bulge outward into the middle ear. The scala vestibuli and scala tympani walls are now deformed with the pressure waves and the vestibular membrane is also pushed back and forth creating pressure waves in the endolymph inside the cochlear duct. These waves then causes the membrane to vibrate, which in turn cause the hairs cells of the spiral organ to move against the tectorial membrane. The bending of the stereo cilia produces receptor potentials that in the end lead to the generation of nerve impulses.
The External or Outer Ear - comprises of the auricle or pinna which is the fleshy part of the outer ear. It is cup-shaped and collects and amplifies sound waves which then passes along the ear canal to the ear drum or tympanic membrane. The rim of the auricle is called the helix and the inferior portion is called the lobule. The external auditory canal is a carved tube and contains a few hair and ceruminous glands which are specialized sebaceous or oil glands. These secrete ear wax or cerumen. Both the hairs and the cerumen help prevent dust and foreign objects from entering the ear. A number of people produce large amounts of cerumen, and this sometimes cause the build up to be impacted and can bri...
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...on on the position of the head in space for static equilibrium making it essential for maintaining appropriate posture and balance, where as dynamic they detect linear acceleration and deceleration. There are two kinds of cells in the two maculae, hair cells and supporting cells. The hair cells are the sensory receptors. Laying over the hair cells are columnar supporting cells that probably secrete the thick, gelatinous, glycoprotein layer called the otolithic membrane and over the membrane is a layer of dense calcium carbonate crystals called otoliths. When the head is tilted, the otoliths shift, and the hairs beneath respond to the change in pressure and bending the hair bundles.
Dynamic equilibrium functions in the three semicircular ducts, the saccule and the utricle. The two ventical ducts are the anterior and posterior semicircular ducts. The lateral semicircular duct is horizontal. In the dilated portion of each duct, the ampulla, is a small elevation called the crista. This contains hair cells and supporting cells which are also covered by a mass of gelatinous material which is called cupula. When the head moves the attached semicircular ducts and hair cells move with it.
Hearing allows us to take in noises from the surrounding environment and gives us a sense of where things are in relation to us. All those little folds on the outside of the ear, called the tonotopic organization, make it so sound waves in the air are directed to the ear canal, where they can be further processed. Once in the ear, the sound waves vibrate the ear drum, which tell the ear exactly what frequency it is sensing. The vibration of the ear drum is not quite enough to send a signal to the brain, so it needs to be amplified, which is where the three tiny bones in the ear come into play. The malleus or hammer, incus or anvil, and stapes or stirrup amplify this sound and send it to the cochlea. The cochlea conducts the sound signal through a fluid with a higher inertia than air, so this is why the signal from the ear drum needs to be amplified. It is much harder to move the fluid than it is to move the air. The cochlea basically takes these physical vibrations and turns them into electrical impulses that can be sent to the brain. This is...
Cochlear implants are electronic devices that sends signals directly to the auditory nerve. Cochlear implants consist of external parts which include the microphone, speech processor, and the transmitter. They also consist of internal parts that must be surgically placed under the skin including the receiver and electrical array. In order for the implant to work, the microphone
Sound is localised to the ear by the pinna, travelling down the auditory canal, vibrating the eardrum. The eardrums vibrations are then passed down through the ossicles, three small bones known as the hammer, anvil and stirrup that then transfer the vibrations to the oval window of the cochlea. The cochlea is filled with fluid that when exposed to these vibrations stimulate the sterocilia. This small hair cells "wiggle" along to certain frequencies transferring the vibrations into electrical impulses that are then sent to the brain. If the ear is exposed to noise levels of too high an intensity the sterocilia are overstimulated and many become permanently damaged . (Sliwinska-Kowalska et. All,
The fresh wound didn’t seem like it would be such a problem until I saw the blood trickling out. Sure, when I had cut my self by grabbing a piece of saw palmetto, I felt my skin ripping and quickly retracted my right hand. However, my want for adventure to explore the tree island overcame the small bit of pain I felt. An adrenaline rush helped me overcome all of the annoyances pushing through the dense brim of the island, like palmetto leaves and spider webs, as well as the myriad of other obstacles upon finally penetrating.
The mechanical motions of the ossicles directly vibrate a small membrane that connects to the fluid filled inner ear. From this point, vibration of the connective membrane (oval window) transforms mechanical motion into a pressure wave in fluid. This pressure wave enters and hence passes vibrations into the fluid filled structure called the cochlea. The cochlea contains two membranes and between these two membranes, are specialized neurons or receptors called Hair cells. Once vibrations enter the cochlea, they cause the lower membrane (basilar membrane) to move in respect to the upper membrane (i.e. --the tectorial membrane in which the hair cells are embedded). This movement bends the hair cells to cause receptor potentials in these cells which in turn cause the release of transmitter onto the neurons of the auditory nerve. In this case, the hair cell receptors are very pressure sensitive. The greater the force of the vibrations on the membrane, the more the hair cells bend and hence the greater the receptor potential generated by these hair cells.
...cines. They may also help you cope with it by teaching you how to cooperate with noise around you. When doctors check your ears that may find OME, it’s thin and watery. If fluid is still present after six weeks the treatment may include having more observations and having to take tests. For us to tell what foods and scents delight us, we use our sense of smell. Your sense of smell helps us to determine what we like to have to eat and wear on different types of occasions. Your sense of smell can also be used for other things like smelling nature around you and smelling the different kind of foods there are around the world. Smell has a chemoreceptor that respond to chemicals in an aqueous solution. Smell receptors are excited by the airborne chemicals that dissolve in fluids coating nasal membranes. The organ of smell is a yellow patch of pseudostratified epithelium.
What would you expect to be the mindset of a misfit kid who isn’t really that popular who is playing baseball with the other kids because he wants to fit in with them instead of being himself? There is such a boy in a first person short story that was written by a worldly-renowned author. In “Eye Ball,” Spiegelman uses characterization to develop the theme of be yourself and don’t try to fit in with others at the expense of showing your true self.
These tasks are accomplished through the mechnoreceptors of the three semicircular canals, the utricle and the saccule (3). Like the neighboring auditory system, each canal has hair cells that detect minute changes in fluid displacement, but unlike the auditory system, the utricle and the saccule send information to the brain regarding linear acceleration and head tilt. Shaking your head ënoí employs one of these canals. Likewise, there is a canal that detects head movement in the ëyesí position, and there is yet another semicircular canal that detects motion from moving your head from shoulder to shoulder (4).
In order to better understand vertigo, it is first necessary to look into where equilibrium and movement are maintained within the body. Equilibrium in our bodies is coordinated primarily by the brain, specifically at the brainstem, located in the neck area. The environment provides the information necessary for the equilibrium center to determine which position to place the body in. There are three main places in which information is received: the eyes provide visual information, the ears provide vestibular and auditory information, and the articulations provide proprioceptive information. In general, the eyes help position the body according to different horizontal angles in relation to the ground. The ears allow the body to acknowledge any type of movement, such as acceleration or deceleration, by registering various sounds (1). Movement is also processed in parts of the brain, as well as in the ears. The frontal lobes of the brain initiate and coordinate the planning of movements. The basal ganglia, in the ears, add control and fluidity to movements, and the cerebellum processes information from and to the rest of the body.
They are found in large numbers which increases the surface area for absorption(3)(4). Microvilli can also be found on the surface of egg cells and white blood cells. A specialised type of microvilli called stereocilia is found in the nose and ears. The stereocilia in the ear are responsible for hearing by detecting sound vibrations(3)(4). Cilia can be both motile and non-motile. In the respiratory system, cilia are responsible for moving/beating the mucus, which contains trapped microorganisms and dust, away from the trachea and up the respiratory tract towards the mouth(2)(3)(7). Non-motile cilia also known as primary cilia can be found on the surface of all cells. Primary cilia have a 9+0 microtubules arrangement and have various functions in mammalian cells, they are most importantly found in the sensory organs where they can sense and respond to chemical stimuli from the external
Then, when I was three years old, I had surgery to get a cochlear implant at the University of Minnesota. A cochlear implant is a small device which bypasses the damaged parts of the ear and directly stimulates the auditory nerve. Signals generated by the implant are sent by the auditory nerve to the brain, which recognizes t...
...for the sense of balance; however, some major organs involved with this system are the semicircular canals (there are three of these), the saccule, and the utricle; all of these are located in the inner section of the ear, below the temporal bone. Some of the main functions of this system as a whole are to create movement, posture, balance, and reflexes. Reflexes are very important because when the head is moved or in movement, it can be helpful in maintaining the vision of an item that is being looked at without causing damage or issues in vision or the eyes. Movement and posture is also one of the biggest functions that the vestibular system provides because without this system and the organs that help provide it, it would be impossible to move and maintain posture even though there are other systems such as the muscular and skeletal system that provide movement.
spiraling clockwise in the northern hemisphere. The opposite happens where air is warmed by the sun or by the Earth's surface temperature. The resulting rising air is above a "low." Near the surface, air flows into the "low" to replace the rising air, spiraling counter-clockwise (Atmosphere 26). Highs and lows react to each other causing a variety of conditions. Driving up or down a mountain leads to a reduction or increase of air pressure in the outer part of the ear, creating a pressure difference across the eardrum, which separates the outer ear from the middle ear. The difference distorts the eardrum, so that sounds are muffled (What is Air Pressure 9). However, this can be taken care of by swallowing air and opening the Eustachian tube between the middle ear and the nasal cavity, which in turn is joined to the mouth.
Hearing is known to be an automatic function of the body. According to the dictionary, hearing is, “the faculty or sense by which sound is perceived; the act of perceiving sound,” (“hearing…”). Hearing is a physical and involuntary act; therefore, unless one is born with a specific form of deafness, everyone has the natural ability to hear sounds. Sounds constantly surround us in our everyday environments, and because we are so accustomed to hearing certain sounds we sometimes don’t acknowledge them at all (or “listen” to them). The dictionary definition of listening is, “to give attention with the ear; attend closely for the purpose of hearing,” (“listening…”).