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Unilateral Hearing Loss
Unilateral hearing loss (UHL) is a type of hearing impairment Hearing loss is a partial or total inability to Hearing, hear. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to Lang ... where there is normal hearing in one ear and impaired hearing in the other ear. Signs and symptoms Patients with unilateral hearing loss have difficulty: * Hearing conversation on their impaired side * Localizing sound * Understanding speech in the presence of background noise * In interpersonal interaction in social settings * Focusing on individual sound sources in large, open environments * Heavy impairment of the Figure–ground (perception), auditory Figure–ground perception In quiet conditions, speech discrimination is no worse than normal hearing in those with partial deafness; however, in noisy environments speech discrimination is almost always severe. The pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audiology
Audiology (from Latin 'to hear'; and from Ancient Greek, Greek branch of learning , ''wikt:-logia, -logia'') is a branch of science that studies hearing, balance, and related disorders. Audiologists treat those with hearing loss and proactively prevent related damage. By employing various testing strategies (e.g. behavioral hearing tests, otoacoustic emission measurements, and electrophysiologic tests), audiologists aim to determine whether someone has normal sensitivity to sounds. If hearing loss is identified, audiologists determine which portions of hearing (high, middle, or low frequencies) are affected, to what degree (severity of loss), and where the lesion causing the hearing loss is found (outer ear, middle ear, inner ear, auditory nerve and/or central nervous system). If an audiologist determines that a hearing loss or vestibular abnormality is present, they will provide recommendations for interventions or rehabilitation (e.g. hearing aids, cochlear implants, appropria ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress (medicine)
Stress, whether physiological, biological or psychological, is an organism's response to a stressor, such as an environmental condition or change in life circumstances. When stressed by stimuli that alter an organism's environment, multiple systems respond across the body. In humans and most mammals, the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis are the two major systems that respond to stress. Two well-known hormones that humans produce during stressful situations are adrenaline and cortisol. The sympathoadrenal medullary axis (SAM) may activate the fight-or-flight response through the sympathetic nervous system, which dedicates energy to more relevant bodily systems to acute adaptation to stress, while the parasympathetic nervous system returns the body to homeostasis. The second major physiological stress-response center, the HPA axis, regulates the release of cortisol, which influences many bodily functions, such as metabolic, psychologica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Conduction
Bone conduction is the conduction of sound to the inner ear primarily through the bones of the skull, allowing the hearer to perceive audio content even if the ear canal is blocked. Bone conduction transmission occurs constantly as sound waves vibrate bone, specifically the bones in the skull, although it is hard for the average individual to distinguish sound being conveyed through the bone as opposed to the sound being conveyed through the air via the ear canal. Intentional transmission of sound through bone can be used with individuals with normal hearing—as with bone-conduction headphones—or as a treatment option for certain types of hearing impairment. Bones are generally more effective at transmitting lower-frequency sounds compared to higher-frequency sounds. Bone conduction is also called the second auditory pathway and not to be confused with cartilage conduction, which is considered the third auditory pathway. Overview Bone conduction is one reason why a person's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlea
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus (cochlea), modiolus. A core component of the cochlea is the organ of Corti, the sensory organ of hearing, which is distributed along the partition separating the fluid chambers in the coiled tapered tube of the cochlea. Etymology The name 'cochlea' is derived from the Latin word for ''snail shell'', which in turn is from the Greek language, Ancient Greek κοχλίας ''kokhlias'' ("snail, screw"), and from κόχλος ''kokhlos'' ("spiral shell") in reference to its coiled shape; the cochlea is coiled in mammals with the exception of monotremes. Structure The cochlea (: cochleae) is a spiraled, hollow, conical chamber of bone, in which waves propagate from the base (near the middle ear and the oval window) to the apex (the top or center of the spiral). The spiral canal of the cochlea is a section of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headband
A headband or hairband is a clothing accessory worn in the hair or around the forehead, usually to hold hair away from the face or eyes. Headbands generally consist of a loop of elastic material or a horseshoe-shaped piece of flexible plastic or metal. They come in assorted shapes and sizes and are used for both fashion and practical or utilitarian purposes. In the UK, horseshoe-shaped headbands are sometimes called " Alice bands" after the headbands that Alice is often depicted wearing in ''Through the Looking-Glass''. History Greeks and Romans The beginning of headbands was no later than around 475 BC to 330 BC, with the ancient Greeks, who wore hair wreaths. The Greeks and Romans wore these pieces for very special occasions or an important event. Cultures such as the Etruscans and Romans started to decorate their wreaths with jewels made up of gold and silver. While wreaths are certainly a likely beginning of today's headbands, some believe that current day hair ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abutment
An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end that provide vertical and lateral support for the span, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support ends of spans unsupported by abutments. Dam abutments are generally the sides of a valley or gorge, but may be artificial in order to support arch dams such as Kurobe Dam in Japan. The civil engineering term may also refer to the structure supporting one side of an arch, or masonry used to resist the lateral forces of a vault.Pevsner, N. (1970) ''Cornwall''; 2nd ed. Harmondsworth: Penguin; p. 245 The impost or abacus An abacus ( abaci or abacuses), also called a counting frame, is a hand-operated calculating tool which was used from ancient times in the ancient Near East, Europe, China, and Russia, until the adoptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastoid Part Of The Temporal Bone
The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, the mastoid part articulates with two other bones. Etymology The word "mastoid" is derived from the Greek word for "breast", a reference to the shape of this bone. Surfaces Outer surface Its outer surface is rough and gives attachment to the occipitalis and posterior auricular muscles. It is perforated by numerous foramina (holes); for example, the mastoid foramen is situated near the posterior border and transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater. The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital. Mastoid process The mastoid process is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Anchored Hearing Aid
A bone-anchored hearing aid (BAHA) is a type of hearing aid based on bone conduction. It is primarily suited for people who have conductive hearing losses, unilateral hearing loss, single-sided deafness and people with mixed hearing losses who cannot otherwise wear 'in the ear' or 'behind the ear' hearing aids. They are more expensive than conventional hearing aids, and their placement involves invasive surgery which carries a risk of complications, although when complications do occur, they are usually minor. Two of the causes of hearing loss are lack of function in the inner ear (cochlea) and when the sound has problems in reaching the nerve cells of the inner ear. Examples of the first include age-related hearing loss and hearing loss due to noise exposure. A patient born without external ear canals is an example of the latter for which a conventional hearing aid with a mould in the ear canal opening would not be effective. Some with this condition have normal inner ear func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hearing Aid
A hearing aid is a device designed to improve hearing by making sound audible to a person with hearing loss. Hearing aids are classified as medical devices in most countries, and regulated by the respective regulations. Small audio amplifiers such as personal sound amplification products (PSAPs) or other plain sound reinforcing systems cannot be sold as "hearing aids". Early devices, such as ear trumpets or ear horns, were passive amplification cones designed to gather sound energy and direct it into the ear canal. Modern devices are computerised electroacoustic systems that transform environmental sound to make it audible, according to audiometrical and cognitive rules. Modern devices also utilize sophisticated digital signal processing, aiming to improve speech intelligibility and comfort for the user. Such signal processing includes feedback management, wide dynamic range compression, directionality, frequency lowering, and noise reduction. Modern hearing aids requi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CROS Hearing Aid
A contralateral routing of signals (CROS) hearing aid is a type of hearing aid that is used to treat a condition in which the patient has no usable hearing in one ear and minimal hearing loss or normal hearing in the other ear. This is referred to as single sided deafness. Mechanism The CROS hearing aid takes sound from the ear with poorer hearing and transmits to the ear with better hearing. The goal of this device is to give the patient two-sided hearing when true bilateral hearing is not possible. The CROS system is an alternative to traditional unilateral hearing aid fittings in which the patient receives no information from the side with hearing loss. Most systems are now wireless and are either behind the ear or custom built in-the-ear systems. These wireless systems have replaced earlier wired units which were bulky and rather fussy. Few people found them beneficial, and by contrast the wireless are easier to use and to wear. There are also systems incorporated into eyegla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tinnitus
Tinnitus is a condition when a person hears a ringing sound or a different variety of sound when no corresponding external sound is present and other people cannot hear it. Nearly everyone experiences faint "normal tinnitus" in a completely quiet room; but this is of concern only if it is bothersome, interferes with normal hearing, or is associated with other problems. The word ''tinnitus'' comes from the Latin language, Latin ''wikt:en:tinnitus#Latin, tinnire'', "to ring." In some people, it interferes with concentration, and can be associated with anxiety and Depression (mood), depression. Tinnitus is usually associated with hearing loss and decreased comprehension of speech in noisy environments. It is common, affecting about 10–15% of people. Most tolerate it well, and it is a significant (severe) problem in only 1–2% of people. It can trigger a fight-or-flight response, as the brain may perceive it as dangerous and important. Rather than a disease, tinnitus is a sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensorineural Hearing Loss
Sensorineural hearing loss (SNHL) is a type of hearing loss in which the root cause lies in the inner ear, sensory organ (cochlea and associated structures), or the vestibulocochlear nerve (Cranial nerves, cranial nerve VIII). SNHL accounts for about 90% of reported hearing loss. SNHL is usually permanent and can be mild, moderate, severe, profound, or total. Various other descriptors can be used depending on the shape of the audiogram, such as high frequency, low frequency, U-shaped, notched, peaked, or flat. ''Sensory'' hearing loss often occurs as a consequence of damaged or deficient cochlear hair cells. Hair cells may be abnormal at birth or damaged during the lifetime of an individual. There are both external causes of damage, including Ear infection, infection, and Ototoxicity, ototoxic drugs, as well as intrinsic causes, including genetic mutations. A common cause or exacerbating factor in SNHL is prolonged exposure to environmental noise, or noise-induced hearing loss. Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
