Neuro Quiz 4 🧠4️⃣

we got this

the structures past the tympanic membrane are called the…

middle ear

what is the scientific term for the ear canal?

external auditory meatus

name ALL structures present in the middle ear

the ossicles, tympanic membrane, tympanic cavity

name ALL structures present in the inner ear

semicircular canals, cochlea, vestibule

name ALL structures in the outer ear

external auditory meatus, pinna, concha

main purpose of external auditory meatus

protects tympanic membrane

The tympanic membrane is ________ (concave or convex?)

concave

The tympanic membrane is attached to the _______ bone

malleus

what is the main purpose of the Eustachian tube?

connects middle ear and nasopharynx, equalizes air pressure

The vestibule plays a role in sensing ____   ______, maintaining _________, and detecting ____ acceleration.

head position, equilibrium, linear

Semicircular canals are ____ _____ canals that detect ______ acceleration of the head and help maintain _______.

fluid filled, rotational, balance

The cochlea is a small, shell-shaped part of the ____   _____ that is approximately ___ mm long in humans, forming a somewhat _____-shaped spiral with ____ turns

inner ear, 35, cone, 3/4th

what is the main purpose of the scala media?

house the organ of Corti, separate the other two membranes

The three parts of the cochlea are the ….

scala vestibuli, scala media, and scala tympani.

the Basilar membrane separates the…

scala tympani and scala media

Reissner’s membrane separates the ….

scala vestibuli and scala media

The oval window is a small membrane-covered opening that connects the…..

middle ear to cochlea

The round window is a small, flexible membrane at the….

end of the cochlea

The round window allows ____ inside the _____ to move

fluid, cochlea

The basilar membrane in the cochlea is organized _______, meaning different regions respond to different sound frequencies.

tonotopically

In the basilar membrane, high frequencies resonate at the___ of the cochlea, while low frequencies resonate at the ___.

base, apex

Movement of the basilar membrane stimulates ______ _________

hair cells

Outer Hair Cells (OHCs) are arranged in ____ rows

three

what is stereocilia and why is it important

tiny hairs that detect sound vibrations and help convert them into signals for the brain

Inner Hair Cells (IHCs) are arranged in ___ row

one

Nerve cells in the cochlea join to form the ______ _____, sending sound to the _____

cochlear Nerve, brain

there are ____ neurons of the central auditory pathway

5

CAP First order neuron?

spinal ganglion

CAP Second order neuron?

Cochlear nuclei

CAP Third order neuron?

Superior olivary complex (first site where binaural [both ears] information is processed)

CAP Fourth order neuron?

Inferior colliculus (midbrain structure where some fibers cross to the opposite side) 

CAP Fifth order neuron?

 Medial geniculate nucleus (thalamus, relays auditory information to the cortex)

what is this image depicting?

Central Auditory Pathway neurons

What structure is indicated by the letter A?

5th, Medial geniculate nucleus

What structure is indicated by the letter B?

4th,Inferior colliculus

What structure is indicated by the letter C?

3rd, Superior olivary complex

What structure is indicated by the letter D?

2nd, Cochlear nuclei

What structure is indicated by the letter E?

1st, spinal ganglion

What are the two reasons for bilateral input in the CAP?

1. the presence of accessory nuclei related to ascending pathways

2. the bilateral representation of impulses from both ears

what feedback system provides a mechanism for regulating selective attention?

auditory modulation

Unilateral lesion to auditory cortex or its pathways causes….?

little to no hearing loss, but will have impaired ability to tell direction and distance of sounds.

Nerve deafness happens when…

the cochlea’s receptor cells or the cochlear nerve become damaged

Nerve Damage hearing loss effects

might cause hearing loss that can affect both ears, depending on how severe the damage is.

Unilateral leison to the hair cells, their ganglion, cochlear nerve, or cochlear nuclei causes…

hearing loss in that same ear. Does not usually cause serious hearing loss.

what are the two main functions of the vestibular system?

1. Keep the head & body balanced

2. Keep the eyes steady while the body is making small movements

Excessive vestibular stimulation causes…

vertigo

the vestibulospinal pathway’s main function is….

equilibrium

Equilibrium depends on…

visual, proprioceptive, and vestibular senses

which otolith organ is almost in the horizontal plane

Utricle

which otolith organ is almost in the vertical (sagittal) plane

Saccule

Inside each of the utricle and saccule is a small thickened area called the ______

macula

The macula helps detect _____ _______

linear acceleration

The cranial nerve associated with the vestibular system is Cranial Nerve ____ , also called the _____________ nerve.

VIII (8), Vestibulocochlear

Lateral vestibulospinal tract controls …….

posture and balance

Medial vestibulospinal tract controls controls….

cervical spinal cord, position/muscles of the head

Retina contains 2 types of photoreceptors, called….

rods and cones

The first-order neurons in the retina are the ________ ____, and the second-order neurons are the _______ ______ whose axons form the optic nerve.

bipolar cells, ganglion cells

Visual Pathway First Stop

Optic nerves

Visual Pathway Second Stop

optic chiasm

Visual Pathway Third Stop

optic tracts

Visual Pathway Fourth Stop

lateral geniculate nucleus (LGN)

Visual Pathway Fifth Stop

optic radiations

Visual Pathway Final Destination

occipital lobe

Binocular field = seen by …

both eyes while focusing on an object

Monocular field = seen by…

lateral portion of the visual field

anopsia means

loss of any field of vision

Monocular blindness = blindness in…

one eye due to damage before the decussation

Bitemporal hemianopsia = blindness in…

temporal fields of both eyes due to damage to the optic chiasm

Contralateral homonymous hemianopsia = blindness in….

visual field opposite the side of lesion due to damage
to the fibers before the LGN

Quadrantanopsia = blindness in…

one fourth of visual field in both eyes due to damage to optic radiations in one hemisphere