Basilar Hair Cells: A Case Study

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.

I) Describe what would happen if there was a thrombosis (clot) in the middle cerebral artery?

Cochlear implants are a small, complex electronic device that can provide a sense of sound to a person who is deaf or severely hard of hearing. The implant consists of two parts; a small receiver, surgically implanted just under the skin above the ear and a larger transmitter that is attached externally. Cochlear implants do not simply amplify sounds like a hearing aid, they bypass the damaged portions of the ear and directly stimulate the auditory nerve. Although these implants can restore a sense of hearing, the sound received from one is very different from normal

Conductive hearing loss is from one or more deformity with the outer, inner, or middle ear which impacts sound from transferring to the nerves 5. Conductive hearing loss is often corrected with surgery, drugs, or hearing aids. Sensorineural hearing loss affects the cochlea, which transfers the sounds vibrations to the nerves 5. Although hearing aids are typically used for conductive hearing loss, a profoundly deaf sensorineural patient needs to complete a 6-month trial with them before they are considered ineffective and referred on for further testing for cochlear implant candidacy 5. Sensorineural hearing loss is primarily due to a malfunctioning cochlea so doctors run a hearing test to see how many decibels can be picked up by the cochlea. For pediatric patients to qualify for implants they need to be considered profoundly deaf in both ears. The tone threshold for mild hearing loss is between 21 and 40 dBHL (decibels Hearing Level) and profound hearing loss is greater than 90 dBHL 5. Typically, a pediatric patient looking for cochlear implants will go through a battery of speech-recognition testing while simultaneously undergoing the audiological

Pure tone audiometry suggested the presence of otosclerosis in the right ear. SRT (50dB for the right ear and 30dB for the left ear) corresponds with the pure tone thresholds. WR scores for the right ear were 96% (85dB) and 100% (70dB) for the left ear, which are consistent with the CHL in the right ear and WNL in the left ear. Typanometry confirmed that finding by revealing a reduced compliance, which indicated less mobility of the tympanic membrane due to increased stiffness. These findings corresponded with the presence of Carhart’s notch at 2000Hz from the audiogram. The absence of OAEs in the right ear also confirmed the conductive component of hearing loss in the right ear due to otosclerosis. The audiology evaluation affirmed that the patient has a decrease in hearing for natural and speech sounds in the right

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

Cochlear implants are biomedical devices that help individuals with severe hearing impairments with auditory sensation. In order to process sound cochlear implants include external and internal components. A microphone, which is part of the external component gathers sound (Petersona, Pisonia, & Miyamoto, 2010). These sound waves from the environment are transferred into electrical signals (Petersen, Gjedde, Wallentin, & Vuust, 2013). The electrical signals are then organized through a series of filters. After this step is completed, the signals are conveyed across the skin to a receiver within the internal components. In the implanted device, further conversion occurs and the signals are delivered to an array of electrodes within the cochlea. Each signal is directed to a specific electrode, this method utilizes tonotopic representation and coding of frequency. Lastly, the electrodes stimulate the auditory nerve (Petersona et al., 2010). These are the main processes involved in the application of cochlear implants. This paper explores some of the current research related to the application of cochlear implants including: language abilities, plasticity and areas for further research.

Of the treatment conditions (#2, 4, 5, 6) #2 (10 mM OB drip 30 minutes) and #5 (5 mM OB Whatman paper 60 minutes) are well suited to an animal model of auditory

Our outer ear is made up of the three tiny bones, the cochlea filled with fluid, and our tiny hair receptors that pick up sounds. Once a person is going deaf or is deaf, that means that hair cells are damaged and they can no longer send sound information to our hearing nerves. The implant “does not amplify sound. It bypasses the missing or damaged hair cells altogether, and delivers more sound information directly to the hearing nerve. The cochlear implant has two parts: 1) the implant, which is surgically placed into the Mastoid bone, and 2) the outer device of a headpiece and processor,” (Bhansali. 2001. Paragraph 7, Lines

Here are some important and basic things to know about cochlear implants, hearing aids, and assistive hearing devices. A cochlear implant is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing in both ears. The implant generates signals that it sends to the auditory nerve, which then passes it onto the brain where they are recognized as sounds. A cochlear implant does not cure deafness or hearing impairment, but it’s a prosthetic substitute which directly stimulates the cochlea. A cochlea is the sense organ that translates sound into nerve impulses to be sent to the brain. Each person has two cochlea, one for each ear. The cochlea is a fluid-filled, snail shaped

In the case of Ms.’s N, she was found to have hearing loss in both ears at the 45-decibel range. According to our book, “A range of 41-55-decibels hearing loss would encompass a moderate hearing loss, hears conventional speech but only at close distances, understanding speech is more difficult with background noises”. (Pg. 291). Therefore, it is important to consider that the extent of her hearing loss is moderate and not severe or profound, nor does it state whether she suffers from vertigo which would change the outcome of her diagnosis. At this point it would help her if she acquired a hearing aid that contains special “noise-reduction circuits” that would aid in reducing the background noise distractions and that includes a telecoil feature. This would decrease the degree of her hearing interfering with her ability to function in her current position. Although there are

Cochlear implants were designed for patients who are profoundly or severely deaf and do not benefit from hearing aids. In addition, individuals with damaged hair cells in their cochlea benefit immensely from cochlear

Now I have the newer version of Hearing aids which are the ones that I can simply insert like earphones but much smaller. However, If I knew from the beginning that the volume of making sounds louder could be adjusted on the Hearing aids I have now, I would’ve got them adjusted long ago and will be able to wear them without feeling like everything sound much more low in volume when taking of the hearing aids because hearing aids are not suppose to do that. I’m currently trying to get back to wearing my Hearing aids for my benefit as I now learn that being being different is

As the textbook describes, hearing loss and impairments are described in terms of loudness (decibels) and pitch (frequency or hertz). Because there is a correlation between general knowledge and the degree of hearing loss, it is imperative that the teacher understand the amount of hearing loss for a student diagnosed with a hearing impairment. The hearing loss may range from slight to profound, depending on the decibel level needed for the individual to hear sounds at different frequencies. Hearing loss can also characterized by where the problem exist in the anatomical system. If the location of the problem is within the outer or middle ear it is a conductive loss. If the problems exist in the inner ear and auditory

This technology gave more power for hearing aids used by the severely hearing impaired (p. C292).