Week 5: Sensation - Hearing and Vision

What is the process by which sound energy is converted into neural signals in the brain?

Hearing involves the transduction of sound energy into neural signals.

What physical dimensions of sound waves correspond to loudness, pitch, and timbre?

Amplitude corresponds to loudness, frequency corresponds to pitch, and complexity corresponds to timbre.

What are the three main parts of the human ear?

The outer ear, middle ear, and inner ear.

What structure in the middle ear vibrates in response to sound waves?

The tympanic membrane (eardrum).

What are the names of the three ossicles in the middle ear?

Malleus, incus, and stapes.

What does the stapes transmit vibrations to in the inner ear?

The oval window of the cochlea.

What is the function of the cochlea?

It is a fluid-filled, spiral-shaped structure that contains the basilar membrane and is involved in hearing.

What are hair cells and where are they located?

Hair cells are auditory receptor cells located in the Organ of Corti on the basilar membrane.

What is the role of stereocilia in hair cells?

Mechanical movement of stereocilia opens ion channels, leading to the transduction of mechanical energy into electrical signals.

How are auditory signals transmitted from the cochlea to the brain?

Signals are sent via spiral ganglion cells to the auditory nerve, then to the brainstem, thalamus, and finally to the primary auditory cortex.

What is place coding of frequency in hearing?

It refers to the organization of the basilar membrane where high frequencies cause maximum displacement near the base and low frequencies near the apex.

What is the primary auditory cortex responsible for?

It maintains tonotopic organization, where nearby cells respond to nearby frequencies.

What is the purpose of cochlear implants?

They stimulate spiral ganglion cells to generate action potentials, bypassing damaged hair cells.

What is the process by which light energy is converted into neural signals?

Vision involves the transduction of light energy into neural signals.

What part of the electromagnetic spectrum can humans see?

Humans see a small part of the electromagnetic spectrum.

What structures focus light onto the retina?

The cornea and lens.

What types of photoreceptors are found in the retina?

Rods (for low light and black and white vision) and cones (for color vision and higher acuity).

What are the three types of cones in the human eye?

L (long wavelength, red), M (medium wavelength, green), and S (short wavelength, blue).

What is the retinotopic arrangement in the retina?

Adjacent points in the visual field are processed by adjacent neurons in the retina.

What is the main visual pathway responsible for conscious visual experience?

The Retinogeniculate Pathway.

What does the Lateral Geniculate Nucleus (LGN) do?

It processes different types of visual information and has multiple layers (magnocellular, parvocellular, koniocellular).

What is the function of the Retinohypothalamic Pathway?

It synchronizes circadian rhythms by sending light information to the suprachiasmatic nucleus (SCN) of the hypothalamus.

What is the Bionic Eye and its purpose?

A retinal implant that generates light flashes corresponding to the visual scene, useful for blindness caused by damaged photoreceptors.