How do hair cells transduce sound?

Recordings of hair cell electrical responses have shown that they transduce sound via sub-micrometer deflections of their hair bundles, which are arrays of interconnected stereocilia containing the mechanoelectrical transducer (MET) channels.

How does the ear hear different frequencies?

As the stapes vibrates, it makes the fluids in the cochlea move in a wave-like manner, stimulating the microscopically small ‘hair cells’. Remarkably, the ‘hair cells’ in the cochlea are tuned to respond to different sounds based on their pitch or frequency of sounds.

How do hair cells transduce an auditory stimulus?

The neurotransmitters diffuse across the narrow space between the hair cell and a cochlear nerve terminal, where they then bind to receptors and thus trigger action potentials in the nerve. In this way, an inner hair cell acts as mechanoreceptor that transduces vibrational into electrical energy.

What structure helps us localize sound?

What structure helps us localize sound? The fluid contained within the membranous labyrinth is called perilymph.

Which part of cochlea determines the pitch of sound?

Inner ear, also called as labyrinth, part of the ear that contains organs of the senses of hearing and equilibrium. The bony labyrinth, a cavity in the temporal bone, is divided into three sections: the vestibule, the semicircular canals, and the cochlea. Cochlea determines the pitch of a sound.

How do auditory hair cells work?

Cochlear hair cells are the sensory cells of the auditory system. These cells possess stereocilia connected to the tectorial membrane. During auditory stimulation, sound waves in the cochlea cause deflection of the hair cell stereocilia, which creates an electrical signal in the hair cell.

How does the function of the cochlear amplifier affect inner hair cell function?

Instead of sound vibration being dampened by the absorption of sound energy by the lamina, the electromotility response of the outer hair cells adds energy, something like negative damping. This phenomenon has been termed the cochlear amplifier. This allows for the exquisite response of the inner hair cells.

What is the mechanism of hearing?

The mechanism of hearing. Sound waves enter the outer ear and travel through the external auditory canal until they reach the tympanic membrane, causing the membrane and the attached chain of auditory ossicles to vibrate.

How does the ear discriminate frequency and amplitude?

Longer sound waves have lower frequency and produce a lower pitch, whereas shorter waves have higher frequency and a higher pitch. The amplitude, or height of the sound wave, determines how much energy it contains and is perceived as loudness (the degree of sound volume).

What is the neural pathway that brings auditory information from the hair cells to the auditory cortex?

Auditory messages are conveyed to the brain via two types of pathway: the primary auditory pathway which exclusively carries messages from the cochlea, and the non-primary pathway (also called the reticular sensory pathway) which carries all types of sensory messages.

What are the 3 cues for sound localization?

Sound source localization is paramount for comfort of life, determining the position of a sound source in 3 dimensions: azimuth, height and distance. It is based on 3 types of cue: 2 binaural (interaural time difference and interaural level difference) and 1 monaural spectral cue (head-related transfer function).

Which receptor is responsible for hearing?

hair cells
The cochlea is filled with two fluids (endolymph and perilymph), inside the cochlea is the sensory receptor — the Organ of Corti — which contains sensory cells with hair-like structures (hair cells) that are the nerve receptors for hearing.

Which part of ear recognizes different frequency of sound?

Auditory hair cells are specialized along the length of the cochlea to respond to specific sound frequencies.

Which part of the ear generates impulses for sound?

The ossicles amplify the sound. They send the sound waves to the inner ear and into the fluid-filled hearing organ (cochlea). Once the sound waves reach the inner ear, they are converted into electrical impulses. The auditory nerve sends these impulses to the brain.

What activates hair cells in the ear?

During auditory stimulation, sound waves in the cochlea cause deflection of the hair cell stereocilia, which creates an electrical signal in the hair cell. Cochlea is a snail-shaped canal in the osseous labyrinth of the inner ear, which contains the sensory organ of hearing—the organ of Corti.

What are the receptor for the auditory pathway?

It houses mechanical receptor cells: 3 rows of outer hair cells and one row of inner hair cells. The base of these cells is embedded within the basilar membrane.

How does bundle branch block affect the heart?

Electrical impulses that cause your heart to beat (contract) start in the heart’s upper right chamber (right atrium) and travel to the lower chambers (ventricles). In bundle branch block, the pathway these impulses follow is delayed or blocked.

What is bundle branch block and how is it treated?

The delay or blockage can occur on the pathway that sends electrical impulses either to the left or the right side of the bottom chambers (ventricles) of your heart. Bundle branch block might not need treatment. When it does, treatment involves managing the underlying health condition, such as heart disease, that caused bundle branch block.

What is the direction of delayed depolarization in a bundle branch block?

The direction of this delayed depolarization vector differs based on the structure that is blocked; the impulse travels anterior toward the right ventricle in RBBB and lateral toward the left ventricle in LBBB. Depending on the anatomical location of the defect which leads to a bundle branch block, the blocks are further classified into:

What causes alternating bundle-branch block in the distal His-Purkinje system?

This pattern of long-short cycles in the distal His-Purkinje system results in alternating bundle-branch block.