CochlearCochleaOssiclesReceptorNeuronsTransductionTympanicOrganOscillationsVibrationsAfferentMiddle earStapesFrequencyCurrentsMechanotransductionMembraneHearingStereociliaOuter hair cellsSensory cellsOrgansSignalsAbstractStimulateMammalsDetectZebrafishCanalRegenerateChronic earStimulusRegenerationDeafnessSynapsesFunctionalVestibular systemBrainVertebratesPostureSoundStimuliStriaFunctionChannelsBodies
Cochlear9
- They derive their name from the tufts of stereocilia called hair bundles that protrude from the apical surface of the cell into the fluid-filled cochlear duct. (wikipedia.org)
- Mammalian cochlear hair cells are of two anatomically and functionally distinct types, known as outer, and inner hair cells. (wikipedia.org)
- Sensorineural (nerve) deafness is loss of auditory function because of loss of cochlear hair cells or auditory nerve neurons. (vin.com)
- Approximately half of congenital SNHL is hereditary and is the result of genetic mutations causing improper development of cochlear hair cells. (intechopen.com)
- In preclinical and clinical studies, progenitor cell therapy (cord blood and mesenchymal stem cells) has shown promise in reversing the underlying pathology of SNHL, the loss of cochlear sensory hair cells. (intechopen.com)
- His clinical practice based at the Stanford Ear Institute and Lucile Packard Children's Hospital focuses on otologic diseases including congenital hearing loss and cochlear implantation, and chronic ear diseases in the pediatric population. (stanford.edu)
- In the new study, which involved researchers from URMC and the Massachusetts Ear and Eye Infirmary, which is part of Harvard Medical School, the team tested the theory that signaling from the EGF family of receptors could play a role in cochlear regeneration in mammals. (regenerativemedicine.net)
- The researchers focused on a specific receptor called ERBB2 which is found in cochlear support cells. (regenerativemedicine.net)
- The researchers found that activating the ERBB2 pathway triggered a cascading series of cellular events by which cochlear support cells began to proliferate and start the process of activating other neighboring stem cells to become new sensory hair cells. (regenerativemedicine.net)
Cochlea19
- Abstract: The exquisite sensitivity and frequency discrimination of mammalian hearing derive from forces generated by outer hair cells (OHCs) within the auditory portion of the inner ear, the cochlea. (usc.edu)
- These forces amplify the sound-induced vibrations within the tissues of the cochlea to enhance quiet sounds and sharpen frequency tuning. (usc.edu)
- Our group has pioneered the technique of using optical coherence tomography to measure sound-induced vibrations within the mammalian cochlea without opening the bone that surrounds it, thus minimizing artifacts. (usc.edu)
- In mammals, the auditory hair cells are located within the spiral organ of Corti on the thin basilar membrane in the cochlea of the inner ear. (wikipedia.org)
- The human cochlea contains on the order of 3,500 inner hair cells and 12,000 outer hair cells at birth. (wikipedia.org)
- The outer hair cells mechanically amplify low-level sound that enters the cochlea. (wikipedia.org)
- citation needed] The inner hair cells transform the sound vibrations in the fluids of the cochlea into electrical signals that are then relayed via the auditory nerve to the auditory brainstem and to the auditory cortex. (wikipedia.org)
- these oscillations are amplified and transmitted through the three ossicles to a membranous opening (the oval window) into the cochlea. (vin.com)
- Conductive deafness is blockage of sound transmission through the outer and/or middle ear without damage to the cochlea. (vin.com)
- Primary deafness results from destruction of hair cells in the cochlea without antecedent events. (vin.com)
- With sensorineural hearing loss (SNHL), the damaged hair cells of the organ of Corti within the cochlea interfere with typical hearing and, as a result, cause impaired language development. (intechopen.com)
- The bony and membranous labyrinth forms the two auditory structures which include the cochlea and the semicircular canals. (acadlly.com)
- The oval windows magnify the vibrations, passing them into the inner ear (cochlea) where the perilymph and endolymph vibrate. (acadlly.com)
- It can be caused by damage to the tympanic membrane, eustachian tube or sensory cells in the cochlea. (acadlly.com)
- The latter contains three canals filled with a liquid: the first conducing the liquid to the tip of the Cochlea, the second taking it back, and the third containing the organ of hearing whose bottom is covered by hair cells. (mpai.community)
- 2. Cochlea in vertebrates detects sound - receptors are tiny hair cells functioning as mechanoreceptors. (msudenver.edu)
- The cochlea is the bony region of the inner ear filled with fluid (perilymph) starting at the oval window as the scala vestibuli and continuing as the scala tympani which pushes against the round window. (msudenver.edu)
- In a new study scientists have been able to regrow the sensory hair cells found in the cochlea -- a part of the inner ear -- that converts sound vibrations into electrical signals and can be permanently lost due to age or noise damage. (regenerativemedicine.net)
- In mice, the cochlea expresses EGF receptors throughout the animal's life, but they apparently never drive regeneration of hair cells," said White. (regenerativemedicine.net)
Ossicles5
- The ear has three compartments: (1) the outer ear, including the pina and the ear canal down to the tympanic membrane, (2) the air-filled middle ear, including the three ossicles (malleus, incus, and stapes) and the connection to the pharynx (the auditory canal), and (3) the fluid-filled inner ear or cochlea, which contains the organ of Corti and the initial portion of the auditory nerve. (vin.com)
- This is a small air-filled chamber in the skull, which is made up of three tiny soft bones (ear ossicles) and Eustachian tube. (acadlly.com)
- The ossicles form a bridge linking the outer and inner ear through a membrane covered opening called round window. (acadlly.com)
- The wave causes the tympanic membrane to vibrate and the vibrations are passed on to the ear ossicles which amplify them. (acadlly.com)
- C) The ear ossicles are abnormally thickened. (easynotecards.com)
Receptor6
- Instead, the influx of positive ions from the endolymph in the scala media depolarizes the cell, resulting in a receptor potential. (wikipedia.org)
- In mammalian outer hair cells, the varying receptor potential is converted to active vibrations of the cell body. (wikipedia.org)
- The inner ear functions as the sensorineural receptor organ of the auditory system, converting an acoustic waveform into an electrochemical stimulus that can be transmitted to the CNS. (medscape.com)
- gem homozygous receptor mutant HCs display normal cell viability, afferent synaptogenesis, and peripheral innervation, yet exhibit strongly reduced extracellular potentials (∼50% of wild-type potentials). (jneurosci.org)
- These currents may be involved in shaping the receptor potential, implying crucial importance for the properties of afferent auditory signals. (jneurosci.org)
- Perhaps during mammalian evolution, there have been changes in the expression of intracellular regulators of EGF receptor family signaling. (regenerativemedicine.net)
Neurons5
- The hair cells in the vestibular system contact VG (vestibular ganglion) neurons, which then send sensory information along nerve cells called mossy fibers to the vestibular region of the cerebellum ( Dow, 1936 ). (elifesciences.org)
- Neurons from the hair cells (black) within the five organs of the vestibular system (left) form different types of synapses - dimorphic, calyx or bouton - with vestibular ganglion (VG) neurons (red). (elifesciences.org)
- These cells are the sole output neurons from the cerebellar cortex and they have a crucial role in motor learning. (elifesciences.org)
- However, this is not the full story because the vestibular region of the cerebellum also contains a high proportion of excitatory neurons called unipolar brush cells (UBCs). (elifesciences.org)
- You have to regenerate sensory hair cells and these cells have to function properly and connect with the necessary network of neurons. (regenerativemedicine.net)
Transduction2
- While performing this sensory transduction process, the inner ear analyzes a sound stimulus in terms of its frequency, intensity, and temporal properties, and it transmits this information to the CNS for further processing and interpretation. (medscape.com)
- The focus of this article is applied physiology of the inner ear, emphasizing the processes involved in transduction and the homeostatic mechanisms necessary for maintaining the inner ear in a functional state. (medscape.com)
Tympanic1
- Snakes lack both an outer ear and a tympanic middle ear, which in most tetrapods provide impedance matching between the air and inner ear fluids and hence improve pressure hearing in air. (biologists.com)
Organ4
- Hair cells are the sensory receptors of both the auditory system and the vestibular system in the ears of all vertebrates, and in the lateral line organ of fishes. (wikipedia.org)
- Sympathetic ganglia comprises the thousands of afferent and efferent nerve cell bodies that run along either side of the spinal cord, connecting major organ systems, such as the renal system, to the spinal cord and brain. (nih.gov)
- Accordingly, in ecdysozoan and vertebrate model organisms, orthologs of Pax2/5/8 are among others involved in the formation of the midbrain/hindbrain boundary, the auditory/geosensory organ systems, and the excretory system. (biomedcentral.com)
- A coordinated tempo-spatial expression of transcription factors is required for cell type specification and the differentiation of the three germ layers into distinct organ systems during bilaterian ontogeny [ 1 ]. (biomedcentral.com)
Oscillations1
- Sound waves reach the outer ear, are guided through a canal, and they hit a thin membrane called Drum whose oscillations are propagated to three tiny bones, Called the Hammer, the Anvil, and the Stirrup, they amplify the oscillations. (mpai.community)
Vibrations1
- Snakes would therefore be expected to have very poor pressure hearing and generally be insensitive to airborne sound, whereas the connection of the middle ear bone to the jaw bones in snakes should confer acute sensitivity to substrate vibrations. (biologists.com)
Afferent1
- We addressed the function of BK Ca by recording sound-induced responses of afferent auditory nerve (AN) fibers from mice with a targeted deletion of the pore-forming α-subunit of BK Ca ( BKα −/− ) and comparing these with voltage responses of current-clamped IHCs. (jneurosci.org)
Middle ear5
- The middle ear. (acadlly.com)
- It separates the external ear from the middle ear. (acadlly.com)
- Therefore, it transmits sound waves from the outer ear to the middle ear. (acadlly.com)
- This is a narrow tube in the middle ear connecting it to the pharynx. (acadlly.com)
- This usually opens when yawning, it allows air to enter or leave the middle ear so that the air pressure on both side of the eardrum is equal. (acadlly.com)
Stapes1
- Stapes pushes against the oval window which communicates with the Inner ear . (msudenver.edu)
Frequency3
- Hair cells that have high-frequency resonance are located at the basal end while hair cells that have significantly lower frequency resonance are found at the apical end of the epithelium. (wikipedia.org)
- 17) A person able to hear only high-frequency sounds would probably have which of the following structural problems in the ear? (easynotecards.com)
- By processing the information that the two sensors (ears) have pre-processed, the brain can create a good internal representation of a 3D audio field in the frequency range of 16 Hz to 16 kHz (approximately). (mpai.community)
Currents1
- Less is known about their role in mammalian inner hair cells (IHCs), mechanosensory cells with unusually large BK Ca currents. (jneurosci.org)
Mechanotransduction1
- Through mechanotransduction, hair cells detect movement in their environment. (wikipedia.org)
Membrane3
- The quickness of the hair cell response may also be due to the fact that it can increase the amount of neurotransmitter release in response to a change of as little as 100 μV in membrane potential. (wikipedia.org)
- The first method, found only in non-mammals, uses electrical resonance in the basolateral membrane of the hair cell. (wikipedia.org)
- The basic principles of this local control are illustrated in the images below and are outlined as follows: First, an anatomic barrier exists between perilymph and endolymph, and it consists of Reissner membrane, the stria vascularis, and the reticular lamina formed by tight junctions between the apices of hair cells and the adjacent supporting cells (see the image above). (medscape.com)
Hearing8
- Damage to these hair cells results in decreased hearing sensitivity, and because the inner ear hair cells cannot regenerate, this damage is permanent. (wikipedia.org)
- While hearing sensitivity of mammals is similar to that of other classes of vertebrates, without functioning outer hair cells, the sensitivity decreases by approximately 50 dB. (wikipedia.org)
- Outer hair cells extend the hearing range to about 200 kHz in some marine mammals. (wikipedia.org)
- Hearing loss is the most common sensory deficit in humans, and may also be so in companion animals where it affects all mammalian species. (vin.com)
- We will present a summary of the effect of hearing loss on auditory development, existing preclinical and clinical data on progenitor cell therapy, and its potential role in the (re)habilitation of non-genetic SNHL. (intechopen.com)
- The ear is for hearing as well as for maintaining balance. (acadlly.com)
- The two major functions of the ear is hearing and balancing. (acadlly.com)
- Our research is focused on finding a way to switch the pathway temporarily, in order to promote both regeneration of hair cells and their integration with nerve cells, both of which are critical for hearing. (regenerativemedicine.net)
Stereocilia2
- The stereocilia number from fifty to a hundred in each cell while being tightly packed together and decrease in size the further away they are located from the kinocilium. (wikipedia.org)
- The deflection of the hair-cell stereocilia opens mechanically gated ion channels that allow any small, positively charged ions (primarily potassium and calcium) to enter the cell. (wikipedia.org)
Outer hair cells1
- Outer hair cells are found only in mammals. (wikipedia.org)
Sensory cells3
- Pax2/5/8 is expressed in regions where sensory cells develop subsequently during ontogenesis. (biomedcentral.com)
- Pax2/5/8 -expressing cells are present in regions where the future sensory cells such as the polyplacophoran esthetes are situated and hence Pax2/5/8 expression probably predates sensory cell development during ontogeny. (biomedcentral.com)
- It comprises four pairs of sensory cells that are located dorsolaterally and ventrolaterally in the episphere of the trochophore. (biomedcentral.com)
Organs1
- Research conducted in the lab of Patricia White, Ph.D., in 2012 identified a family of receptors -- called epidermal growth factor (EGF) -- responsible for activating support cells in the auditory organs of birds. (regenerativemedicine.net)
Signals1
- UBCs essentially create an intermediate step in the circuitry, where signals sent between mossy fibers and granule cells can be modified. (elifesciences.org)
Abstract1
- Abstract: The embodied mammalian brain evolved to adapt to an only partially known and knowable world. (rctn.org)
Stimulate2
- The impulses then stimulate the auditory nerves of the acoustic branch to the brain for interpretation. (acadlly.com)
- A third experiment involved testing two drugs, originally developed to stimulate stem cell activity in the eyes and pancreas, that are known activate ERBB2 signaling. (regenerativemedicine.net)
Mammals1
- Mammals have two ears on each side of the head. (acadlly.com)
Detect2
- This circuitry starts with the vestibular system: a sensory system in the inner ear that relies on hair cells to detect movements, and to provide our sense of balance and spatial awareness. (elifesciences.org)
- systems can detect water movement due to hair cells called neuromasts arranged in a line along the sides of the body. (msudenver.edu)
Zebrafish2
- However, other organisms, such as the frequently studied zebrafish, and birds have hair cells that can regenerate. (wikipedia.org)
- Via positional cloning, we show that mutations in a zebrafish LTCC encoding gene, cav1.3a , underlie the auditory-vestibular defects of gemini ( gem ) circler mutants. (jneurosci.org)
Canal2
- The pinna collects sounds, detects their direction and directs them into the canal called external auditory meatus (ear tube). (acadlly.com)
- Also, wax blocking the ear canal, infection of the ear or sudden very loud or constant noise causes deafness. (acadlly.com)
Regenerate1
- However, scientists have long observed that other animals -- namely birds, frogs, and fish -- have been shown to have the ability to regenerate lost sensory hair cells. (regenerativemedicine.net)
Chronic ear1
- A) The tympanum is damaged because of chronic ear infections. (easynotecards.com)
Stimulus1
- Derivatives of the EEG technique include evoked potential s (EP), which involves averaging the EEG activity time-locked to the presentation of a stimulus of some sort (visual, somatosensory , or auditory). (explained.today)
Regeneration2
- In parallel, his research program focuses on inner ear hair cell development and regeneration. (stanford.edu)
- Furthermore, it appears that this process not only could impact the regeneration of sensory hair cells, but also support their integration with nerve cells. (regenerativemedicine.net)
Deafness1
- The major disease of the ear is deafness. (acadlly.com)
Synapses2
- UBCs form synapses with granule cells (grey), which in turn make contact with Purkinje cells (dark blue), which convey motor responses to the rest of the body. (elifesciences.org)
- A single mossy fiber can activate hundreds of granule cells which, in turn, form synapses with the dendrites of Purkinje cells. (elifesciences.org)
Functional1
- Progenitor cell therapy may also allow functional reorganization of the auditory pathways including primary auditory cortex (Heschl's gyrus). (intechopen.com)
Vestibular system1
- Damage to hair cells can cause damage to the vestibular system and therefore cause difficulties in balancing. (wikipedia.org)
Brain3
- Impulses are set up and transmitted through the vestibular branch of the auditory nerves to the brain for interpretation. (acadlly.com)
- 1) When the mammalian brain compares the actual temperature of the body to the preferred temperature of the body, which general component is being used? (easynotecards.com)
- The wave of the liquid causes the hair cells to move and their bending activates a neural response in the auditory nerve fibbers of the eighth cranial nerve to the brain. (mpai.community)
Vertebrates1
- This so-called somatic electromotility amplifies sound in all land vertebrates. (wikipedia.org)
Posture1
- How does the inner ear communicate with the cerebellar cortex to maintain balance and posture? (elifesciences.org)
Sound2
- It allows the passage of sound waves from the pinna to the ear drum. (acadlly.com)
- The pinna detects and collects sound waves in the air and concentrates them and passes them on through the external auditory meatus. (acadlly.com)
Stimuli2
- The hair bundles are arranged as stiff columns that move at their base in response to stimuli applied to the tips. (wikipedia.org)
- It is thought that this tonic release is what allows the hair cells to respond so quickly in response to mechanical stimuli. (wikipedia.org)
Stria2
- Part of the mechanism by which the stria for maintains these ionic levels involves pigment cells B melanocytes. (vin.com)
- These enzymes are located within the marginal cells of the stria and the underlying spiral ligament. (medscape.com)
Function1
- Their function is assisted by a Na + /Cl - /K + cotransporter located in the marginal cells. (medscape.com)
Channels2
- It is affected by the closing mechanism of the mechanical sensory ion channels at the tips of the hair bundles. (wikipedia.org)
- L-type Ca 2+ channels (LTCCs) drive the bulk of voltage-gated Ca 2+ entry in vertebrate inner ear hair cells (HCs) and are essential for mammalian auditory processing. (jneurosci.org)
Bodies1
- The amplification may be powered by the movement of their hair bundles, or by an electrically driven motility of their cell bodies. (wikipedia.org)