Hearing, Language, and Lateralization (Psych 2113 Exam 2)

Pinna / Auricle (Outer Ear)

The visible, cartilage-based outer part of the ear that projects from the head (Its primary function is to collect, amplify, and funnel sound waves into the auditory canal)

Tympanic Membrane (Outer Ear)

A thin, conical membrane separating the outer ear from the middle ear (It is crucial for audition, converting acoustic energy into mechanical vibrations for transmission to the ossicles)

Ossicles (Middle Ear)

The three tiny bones in the middle ear, the malleus (hammer), incus (anvil), and stapes (stirrup) (It mechanically transmits and amplifies sound-induced vibrations from the eardrum to the cochlea)

Malleus (Middle Ear)

Is the largest of the three small ossicles in the middle ear (Crucial for hearing by transmitting sound vibrations from the tympanic membrane (eardrum) to the incus. It acts as a lever to amplify sound and, due to its connection to the ear drum, is essential for auditory.)

Incus (Middle Ear)

A tiny bone in the middle ear that transmits sound vibrations from the malleus to the stapes (It is essential for hearing, acting as a key component of the ossicular chain that amplifies sound waves and transfers them to the inner ear)

Stapes (Middle Ear)

The smallest bone in the human body, located in the middle ear between the incus and the oval window (It transmits sound vibrations from the incus to the oval window of the inner ear, essential for transforming sound waves into neural signals for hearing)

Oval Window (Inner Ear)

It is located at the base of the cochlea, forming the interface between the middle ear's ossicles (specifically the stapes footplate) and the inner ear (When sound waves hit the eardrum, the ossicles vibrate, and the stapes pushes against it, forcing fluid inside the cochlea to move)

Round Window (Inner Ear)

A membrane-covered opening in the cochlea of the inner ear (It vibrates in the opposite phase to the oval window, permitting fluid motion inside the cochlea, which is critical for hearing)

Cochlea (Inner Ear)

A snail-shaped, fluid-filled structure in the inner ear (It is the primary site for auditory transduction, where sound waves are converted into electrical signals)

Basilar Membrane

It acts as the base, or floor, for the hair cells within the organ of Corti (It serves as the primary mechanism for sensory transduction in hearing, converting mechanical energy from sound waves into electrical signals)

Thalamus

The critical subcortical relay station and information bottleneck for auditory data travelling from the inferior colliculus in the midbrain to the primary auditory cortex

Pitch

The perceived highness or lowness of a sound (linked to frequency)

Loudness

The perceived intensity or volume (linked to amplitude)

Timbre

The distinct "flavor" or quality that distinguishes sounds

McGurk Effect

A perceptual phenomenon demonstrating that visual speech (lip movements) can conflict with and alter auditory speech perception, creating a third, illusory sound

Synesthesia

A neurological and perceptual condition where the stimulation of one sensory or cognitive pathway (e.g., hearing music) automatically and involuntarily triggers experiences in a second, unrelated pathway (e.g., seeing colors)

Location of Auditory Cortex

The part of the temporal lobe (specifically within the lateral sulcus on the Heschl’s gyrus) responsible for processing sound, pitch, and volume

Broca’s Area

Responsible for speech production and articulation

Wernicke’s Area

Responsible for understanding language and comprehension

Non-Fluent Aphasia

Characterized by slow, broken, or effortful speech, but generally, comprehension remains intact

Fluent Aphasia

Characterized as nonsensical "word salad" speech, where the person cannot understand or produce meaningful language

Laterality

The preference for or superior functioning of one side of the body or brain over the other

Left Hemisphere

Dominates language, logic, and sequential processing

Right Hemisphere

Specializes in spatial awareness, intuition, and emotion recognition

Wada Test

A neurological exam used to diagnose and treat epilepsy

Corpus Callosotomy

A surgical procedure that severs the bundle of nerve fibers connecting the left and right brain hemispheres (primarily to treat severe, drug-resistant epilepsy by stopping seizure signals from spreading between sides)

Hemispatial Neglect

A neuropsychological condition where damage to one brain hemisphere (commonly the right parietal lobe) causes a patient to lose awareness of, and fail to attend to, the opposite side of their environment and body