Regulator of inner ear progenitor fate and outer hair cell function

The ear is an extraordinary human organ that many people take for granted until it doesn’t function. It is the only device that allows the human to hear sounds in their environment. The ear is made up of many parts that distinguish various sounds through different means. The ear anatomy and physiology along with how sound waves are transmitted into meaningful sounds will help one understand how hearing loss occurs.

(2005) neurofibromatosis type II is a rare condition with an incidence of 1 in 25,000 persons and a penetrance of nearly 100% by age sixty. NFII is an autosomal dominant heritable neoplasia syndrome as defined by Asthagiri et al. (2012). The hallmark of this disorder is the development of bilateral acoustic neuromas, also known as cochleovestibular schwannomas (CVSs), on the auditory nerve. According to previous research, bilateral CVSs are present in 90-95% of NFII patients (Evans, et al., 1992). These non-cancerous tumors are a result of an NFII gene mutation specifically affecting a protein called merlin, also known as schwannomin. This protein acts as a suppressor, keeping cells from growing too rapidly. When the mutation occurs in the gene, it leads to a production of non-functioning merlin protein that cannot regulate growth and division of cells leading to acoustic neuromas. Although it is known how these neuromas form, the way that these neuromas cause hearing loss is not yet fully understood. Asthagiri et al. (2012) stated that “the most frequently cited hypothesis is that the enlarging CVS causes hearing loss through direct compression and stretching of the cochlear nerve.” Neurofibromatosis type II is characterized by bilateral acoustic neuromas, and the surgery to remove these neuromas generally results in severe damage to the auditory nerve causing deafness (Jackson, Mark, Helms, and Behr,

To do this, the researchers exposed a second group of adult quail to the same hearing-damaging sound as the first and then injected them with radiolabeled thymidine. This allowed researchers to use autoradiography that produce low levels of background issues as well as being able to see 10 to 20 grains over red blood cells. The control birds were still given the injections, however, they were not exposed to the sound. The experimental group experienced the same pattern of damage as the birds in the previous experiment and thymidine was seen over hair cells and support cells in the damaged area. There was no thymidine observed outside of the damaged area. The transition zone of the basilar membrane, where tall and short hair cells are integrated, it seemed that the short cells were more often labeled than the tall cells. Tall cells do not lack the afferent auditory-nerve fiber innervation that is seen in short cells making them a more useful candidate for labeling. The researchers failed to identify location and mechanism of the activation of the precursor cells but remained hopeful that there may exist a way to restore inner ear sensory losses that are caused from injury of hair

Attachment theory examines the mannerisms of the infant and caregiver, how they relate to each other, and how they reinforce each others’ behaviors. Touching, tickling, holding, picking up, vocalizing, looking, and both proto-imperative and proto-declarative pointing are all part of those behaviors. A safe haven is generally the physical location about the caregiver where the infant feels safe while a safe harbor is the area around the caregiver where the infant feels comfortable to explore their world. Through the Strange Situation test, Ainsworth and Mains determined four categories or styles of attachment, which have been both praised and criticized through the years but remain generally consistent, even when performed in multiple cultures:

First I will explain how hearing loss works, So it may be no surprise that loud sounds can damage hearing, but what actually happens is that the pain is caused by damage to the nerves in your ear. For example, if you hear something really loud close to your ear the nerves get hit by a huge wave of sound that can damage your hearing. Furthermore, there is the question

Most existing research and models of auditory neuropathy has utilised gerbils. At present no robust model of auditory neuropathy in guinea pigs exists; previous guinea pig models have been used but these were not robust and were susceptible to confounding.

As an undergraduate, I performed research on deafness, investigating hearing regeneration and unique auditory phenotypes. Based on my work, I was selected to be a Post-Baccalaureate Fellow at the National Institute on Deafness and Other Communication Disorders within the National Institutes of Health. This is a two-year program (07/14-07/16). I lead three projects focused on novel clinical therapies to prevent hearing loss from ototoxic drugs—drugs that cause hearing loss in hundreds of thousands of patients. There exists the need for therapies that protect the inner ear from ototoxic drugs without altering their therapeutic effects, and the focus of my research has been to help develop novel therapies.

Cochlear implants, the surgical device which the media has frequently offered as the miracle cure for deafness, has been utilized as a treatment for hearing loss since the early 1960s (Paludnevicience & Harris, 2011, p.100). In patients with a hearing loss due to damage of hair cells in the inner ear, cochlear prostheses are able to provide some degree of hearing restoration by bypassing these structures and transmitting sounds directly to the auditory nerve (Paludneviciene & Harris, 2011, p. 100). With its start in the mid twentieth century, the technological resources available to the creators of cochlear implants limited their ability to provide patients a natural hearing experience. Though they initially provided only limited gains to deaf

Hearing loss is a drastic change in your everyday life no matter which type it is that you

While sensorineural deafness can be the result of tiny hair cells being damaged, this can also occur when the auditory nerve is damaged (Better Hearing Institute, n.d.). Sensorineural deafness changes the ability of hearing faint sound and reduce the intensity of sound, creating difficulties for the person suffers from it to understand others (hearcom, n.d.). The causes of sensorineural deafness may vary, the exposure to loud noises, aging, medicines, illnesses, head trauma, or malformation in the structure of the inner ear are all potential causes (Better Hearing Institute, n.d.). Genetic also play as a role in the cause of sensorineural deafness. While sensorineural hearing loss is irreversible, researchers have found a way to help the patients to be able to hear better. Through a cochlear implant, an electronic device that replaces the function of the damaged inner ear and provide sound signal to the brain, people who suffer from sensorineural hearing loss would be able to hear (cochlear,

Noise induced hearing loss affects the hair cells of the cochlea and typically develops over years of exposure to noise (Kirchner et al., 2009). Although noise induced hearing loss typically develops over years, noise trauma occurs after one incidence of excessive noise exposure, such as an explosive blast or fireworks. Due to the nature of noise exposure, a noise induced hearing loss typically occurs bilaterally; however, in certain environments, asymmetrical hearing losses can occur as the result of noise exposure (Bess & Humes, 2009; Kirchner et al., 2012). Currently, there is no treatment for noise induced hearing loss. Nevertheless, hearing loss can easily be prevented by limiting noise levels and time of exposure (Fligor, 2011). Approximately 10 million Americans are currently suffering from noise induced hearing loss and an additional 30 to 50 million Americans are exposed to excessive noise levels each day (Fligor, 2011). In recent decades, noise induced hearing loss has become one of the leading occupational hazards in

If you don't protect you hearing your cells will disintegrate and they do not grow back nor heal.

Melanin is also said to be linked with hearing. Melanocytes are present in the inner ear, the eye, and in the membrane that covers the brain and spinal cord. It has been demonstrated that melanin deposits in these areas are proportional to the amount of melanin found in the skin . These areas of the body, similar to the skin, are exposed to high-energy free radicals that can damage the surrounding cells, and thus causing a lower threshold for hearing.

The simple answer is yes, for you and for those around you. Hearing loss may cause you to miss words or conversations, and other sounds such as a phone ringing, a doorbell, or a car horn. Missing out on conversations and other sounds can lower a person’s quality of life in many ways. Hearing loss can affect our enjoyment of life, particularly in our relationships with friends, loved ones, and even at our job.

Our ears – including our outer, middle, and inner, are our body’s organ for hearing. The real purpose of our outer ear isn’t to hold our hair back or keep our sunglasses on, but to capture sound vibrations like a cup and direct them through the skull where they are converted into action potentials in a “sensory dendrite” that is connected to the “auditory nerve” (Farabee, 2001). The brain combines the input of our two ears to determine the direction and distance of sounds.