ch 6

Auditory System

The sensory system responsible for detecting sound and translating it into neural signals for the brain.

Georg von Békésy

Awarded the Nobel Prize for discovering the mechanics of the basilar membrane in the cochlea.

Cochlea

A spiral structure in the inner ear responsible for converting sound vibrations into neural activity.

Hearing Loss

A condition defined as a decrease in sensitivity to sound.

Conduction Deafness

Hearing impairment due to problems getting sound to the inner ear.

Sensorineural Deafness

Hearing loss caused by damage to the hair cells or auditory nerve.

Central Deafness

Deafness resulting from damage to the brain areas that process sound.

Inner Hair Cells (IHCs)

Sensory cells in the cochlea that transmit sound information to the brain.

Outer Hair Cells (OHCs)

Cells that amplify sound vibrations and fine-tune auditory perception in the cochlea.

Frequency (Hz)

The number of cycles per second of a sound wave, perceived as pitch.

Amplitude (dB)

The intensity of a sound, measured in decibels, perceived as loudness.

Basilar Membrane

A membrane in the cochlea that responds to sound frequencies and is crucial for hearing.

Ossicles

The three tiny bones in the middle ear (malleus, incus, stapes) that transmit sound vibrations.

Tympanic Membrane

Also known as the eardrum, it vibrates in response to sound waves.

Tonotopic Organization

The spatial arrangement of where sounds of different frequency are processed in the auditory system.

Tuning Curve

A graph that illustrates the responsiveness of a particular auditory neuron to different frequencies.

Stereocilia

Microscopic hair-like structures on hair cells that bend in response to sound vibrations.

Organ of Corti

The sensory organ within the cochlea containing hair cells that transduce sound into neural signals.

Vestibular System

The sensory system responsible for balance and spatial orientation.

Pinnae

The outer parts of the ears that capture and direct sound waves into the ear canal.

Activation of Auditory Nerve Fibers

The process by which hair cells in the cochlea send signals to the brain about sound.

Pitch

The perception of how high or low a sound is, often related to the frequency of the sound.

Taste Buds

Sensory organs on the tongue that detect taste stimuli.

Olfaction

The sense of smell, involving the detection of airborne chemicals.

Vomeronasal System

A secondary olfactory system involved in detecting pheromones in many vertebrates.

Transduction

The process by which sensory signals are converted into neural signals.

Heschl's Gyrus

The primary auditory cortex where sound processing begins.

Cochlear Implants

Devices that provide a sensation of sound to a person who is profoundly deaf or severely hard of hearing.

Temporal Coding Theory

The theory that sound frequency is represented by the rate of action potentials in auditory neurons.

Place Coding Theory

The theory that different frequencies are perceived based on the location of activity along the cochlea.

Motion Sickness

A condition characterized by nausea and disorientation caused by conflicting sensory messages.

Interaural Intensity Differences (IIDs)

Differences in loudness between the two ears, used to locate sound sources.

Interaural Temporal Differences (ITDs)

Differences in the timing of sound arrival between the two ears, aiding in sound localization.

Taste Sensitivity Distribution

The variation in sensitivity to different tastes across different regions of the tongue.

Amusia

A condition where individuals have difficulty with pitch perception or musical ability.

Anosmia

A condition characterized by the loss of the sense of smell.

Glomerulus

A spherical structure in the olfactory bulb receiving input from olfactory receptor neurons.

Flavor

The combination of taste and smell sensations derived from food.

Sound Shadow

The phenomenon whereby one ear receives a sound at a lower intensity due to the head obstructing the other ear.

Umami

The savory taste associated with amino acids, detected by specific receptors in taste buds.

GBPs (G-protein coupled receptors)

Receptors that transduce various sensory signals, including taste and smell, via second messenger systems.

Tastes

The basic sensations detected via the taste buds: sweet, sour, salty, bitter, and umami.