Ch. 9: Hearing and Language

Chapter 9 of Garret 6e Brain and Behavior

Adequate Stimulus

The energy form for which a receptor is specialized.

Agraphia

The inability to write due to brain damage.

Alexia

The inability to read due to brain damage.

Angular Gyrus

A gyrus at the border of the parietal and occipital lobes containing pathways that connect the visual area with auditory, visual, and somatosensory association areas.

Aphasia

Language impairment caused by damage to the brain.

Auditory Object

A sound that we recognize as having an identity that is distinct from other sounds.

Basilar Membrane

The membrane in the cochlea that separates the cochlear canal from the tympanic canal.

Broca’s Aphasia

Language impairment caused by damage to Broca’s area and surrounding cortical and subcortical areas.

Cochlea

The snail-shaped structure where the ear’s sound-analyzing structures are located.

Cochlear Canal

The middle canal in the cochlea, which contains the organ of Corti.

Cocktail Party Effect

The ability to sort out meaningful auditory messages from a complex background of sounds.

Coincidence Detectors

Neurons that fire most when they receive input from both ears at the same time.

Complex Sound

A sound composed of more than one pure tone.

Dyslexia

An impairment of reading, which can be developmental or acquired through brain damage.

Eustachian Tube

The connection between the middle ear and the oral cavity, equalizing air pressure differences.

Frequency

The number of cycles or waves of alternating compression and decompression of sound in a second.

Frequency-Place Theory

The hypothesis that frequency discrimination is based on neuron activity and the place of greatest activity on the basilar membrane.

Frequency Theory

Hypotheses that state the frequency of a sound is represented in the firing rate of auditory neurons.

Grammar

The consistent set of rules of a particular language.

Head-Related Transfer Function (HRTF)

Spectral frequency alterations to a sound as it passes through the head, aiding sound localization.

Inner Hair Cells

About 3,500 hair cells on the basilar membrane that produce most of the auditory signal.

Intensity

The physical energy in sound; the sound’s amplitude.

Interaural Level Difference

A binaural cue to sound location based on the sound shadow created by the head.

Interaural Timing Difference (ITD)

A binaural cue to sound location due to the time sound takes to travel between ears.

Language

A structured system of communication with a common set of rules.

Language Acquisition Device

A hypothesized part of the brain dedicated to language learning.

Loudness

Our experience of sound intensity.

Organ of Corti

The sound-analyzing structure on the basilar membrane of the cochlea.

Ossicles

Tiny bones in the middle ear that transfer vibration from the tympanic membrane to the cochlea.

Outer Hair Cells

Three rows of cells in the cochlea that amplify sound output and sharpen frequency tuning.

Perception

The interpretation of sensory information.

Phonological Hypothesis

The idea that dyslexia's fundamental problem is impaired phoneme processing.

Pinna

The ear flap on each side of the head.

Pitch

The experience of the frequency of a sound.

Place Theory

The theory that frequency is identified by the location of maximal vibration on the basilar membrane.

Planum Temporale

The area in each temporal lobe where Wernicke’s area is located.

Prosody

The use of intonation, emphasis, and rhythm in speech.

Pure Tone

A sound consisting of a single frequency.

Receptor

A cell that responds to a particular form of energy.

Sensation

The acquisition of sensory information.

Tectorial Membrane

A shelf-like membrane overlying the hair cells in the cochlea.

Telephone Theory

A theory stating that auditory neurons transmit actual sound frequencies to the cortex.

Tonotopically Organized

Neurons from adjacent receptor locations project to adjacent cells in the auditory cortex.

Tympanic Membrane

The eardrum; its vibration transmits sound energy to the ossicles.

Volley Theory

A hypothesis that states groups of neurons follow the sound frequency when it exceeds a neuron's firing rate.

Wernicke’s Aphasia

Language impairment resulting from damage to Wernicke’s area.