Ear diagram

• Hearing: The eardrum vibrates when sound waves enter the ear canal. Ossicles, three tiny bones (including the stapes, the smallest bone in the body), pass vibrations to the oval window, which is a membrane at the entrance to the inner ear. • Balance: Balance is achieved through a combination of the sensory organ in the inner ear, visual input, and information received from receptors in the body, especially around joints. The information processed in the cerebellum and cerebral cortex of the brain allows the body to cope with changes in speed and the direction of the head. The ear is divided into three parts: • Outer ear: The outer ear includes an ear canal that is is lined with hairs and glands that secrete wax. This part of the ear provides protection and channels sound. The auricle or pinna is the most visible part of the outer ear and what most people are referring to when they use the word “ear.” • Middle ear: Three tiny bones — the malleus, incus, and stapes— within the middle ear transfer sound vibrations from the eardrum to the inner ear. The middle ear is important because it is filled with numerous air spaces, which provide routes for infections to travel. It is also the location of the Eustachian tube, which equalizes the air pressure between the inner and outer surfaces of the tympanic membrane (eardrum). • Inner ear: The inner ear, also called the labyrinth, operates the body’s sense of balance and contains the hearing organ. A bony casing houses a complex sy...

Contents • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Human ear The ear is divided into three anatomical regions: the external ear, the middle ear, and the internal ear (Figure 2). The external ear is the visible portion of the ear, and it collects and directs sound waves to the eardrum. The middle ear is a chamber located within the petrous portion of the temporal bone. Structures within the middle ear amplify sound waves and transmit them to an appropriate portion of the internal ear. The internal ear contains the sensory organs for equilibrium (balance) and hearing. Figure 1. Ear structure Parts of the ear External (Outer) Ear The external (outer) ear consists of the auricle, external auditory canal, and eardrum (Figure 1 and 2). The auricle or pinna is a flap of elastic cartilage shaped like the flared end of a trumpet and covered by skin. The rim of the auricle is the helix; the inferior portion is the lobule. Ligaments and muscles attach the auricle to the head. The external auditory canal is a curved tube about 2.5 cm (1 in.) long that lies in the temporal bone and leads to the eardrum. The tympanic membrane or ear drum is a thin, semitransparent partition between the external auditory canal and middle ear. The tympanic membrane is covered by epidermis and lined by simple cuboidal epithelium. Between the epithelial layers is connective tissue composed of collagen, elastic fibers, and fibroblasts....

Understand the science of hearing and how humans and other mammals perceive sound The human ear, like that of other ce) as the labyrinth. It is a complicated system of fluid-filled passages and cavities located deep within the rock-hard petrous portion of the temporal bone. The inner ear consists of two functional units: the

• Helix: The outermost curvature of the ear, extending from where the ear joins the head at the top to where it meets the lobule. The helix begins the funneling of sound waves into the ear • Fossa, superior crus, inferior crus, and antihelix: These sections make up the middle ridges and depressions of the outer ear. The superior crus is the first ridge that emerges moving in from the helix. The inferior crus is an extension of the superior crus, branching off toward the head. The antihelix is the lowest extension of this ridge. Fossas are the depressions between these ridges. These shapes work together to funnel sound waves collected at the helix toward the middle ear • Concha: The concha is the depressed area at the opening of the middle ear, or the external acoustic meatus. The concha is the final point that directs sound into the ear • Tragus and antitragus: These two cartilage prominences border the concha at the top and bottom • Lobule: The lobule is the bottom-most part of the ear, often called the • External acoustic meatus: This inch-long section is sometimes called the ear canal, and serves as the bridge between the outer and middle ear. It’s a hollow tube that curves slightly downward as it moves into the ear toward the tympanic membrane, or Anatomical Variations While ears may seem simple and functional, they are also very unique. The exact size and shape of the outer ridges of the ear and the lobule are different for everyone. Genetics play a role in the size a...

The human body is like a big machine, and various processes take place inside it. With the help of the various organs and tissues, it carries out some of the most marvelous tasks, that are no less than a miracle! One such organ is the ear that helps us in the process of hearing and balancing. The sound waves entering the ear get converted into electric impulses for the brain to understand and interpret. Let us take a look at the human ear structure with the help of a diagram, and understand its functions a little more closely. • Helix:It is the prominent outer rim of the external ear. • Antihelix: It is the cartilage curve that is situated parallel to the helix. • Crus of the Helix: It is the landmark of the outer ear, situated right above the pointy protrusion known as the tragus. • Auditory Ossicles: The three small bones in the middle ear, called malleus, stapes, and incus, are connected. These bones together are called the auditory ossicles, and their purpose is to let the sound that strikes the eardrum, further into the inner ear. • Oval Window: Oval window is the opening covered by a thin membrane, which connects the middle ear to the inner ear. • External Auditory Canal: External auditory canal or ear canal, is the channel from which the sound enters from the outside ear to the eardrum. • Eardrum/Tympanic Membrane: It is the thin membrane located between the external ear canal and the middle ear. • Cochlea: Cochlea is tiny conical structure situated in the inner ear...

Synonyms: External auditory meatus, External acoustic pore , The ear is a complex part of an even more complex sensory system. It is situated bilaterally on the • • • Key facts about the ear Function Hearing and maintaining balance External ear Parts: auricle, external acoustic meatus, tympanic membrane Function: capture and conduction of sound Middle ear Parts: tympanic cavity, auditory ossicles, muscles of the ossicles Function: transforming a high-amplitude low-force sound wave into a low-amplitude high-force vibration and transmitting it to the internal ear Internal ear Parts: bony labyrinth (vestibule, semicircular canals, cochlea) and membranous labyrinth (utricle, saccule, semicircular ducts, cochlear duct) Function: - Bony labyrinth supports its membranous counterparts - Utricle and saccule provide information about the position of the head - Semicircular ducts provide information about movements of the head - Cochlear duct provides hearing information Clinical relations Auricular hematoma, otitis (externa, media, interna), blockage of the auditory (Eustachian) tube, high tone deafness This mixture of + Show all External ear The external ear, like the middle ear, serves only to conduct sound to the inner ear. It consists of the auricle and external acoustic meatus (or ear canal). Key facts about the external ear Parts Auricle, external acoustic meatus Blood supply Posterior auricular, anterior auricular, minor branches of the occipital, deep auricular, stylomast...