PSYCH 230 Chapter 11 The Auditory Brain and Sound Localization

Acoustic Shadow

the area on the side of the head opposite from the source of a sound in which the loudness of a sound is less because of blocked sound waves

Architectural acoustics

the study of how physical spaces such as concert halls affect how sounds are reflected in a room

Auditory core region

an area of the auditory cortex, consisting of the primary auditory cortex, the rostral core, and the rostrotemporal core

Auditory cotrex

the areas in the temporal cortex that process auditory stimuli

Auditory scene analysis

the process of identifying specific sounds-producing objects from a complex set of sounds from different objects at varying and overlapping frequencies

Azimuth

the left-right or side-to-side aspect of sound localtization

Belt

a region of the auditory cortex that wraps around the auditory core regions

Biosonar

a process whereby animals emit sounds and then use comparisons of the emitted sounds and their returning echoes to sense the world around them

Cochlear nucleus

a structure int he brain stem that receives input from the inner hair cells

Cone of confusion

a region of positions in space in which sounds create the same interaural time and interaural level differences

distance

how far sound is from the listener and whether it is in front of or behind the listener

elevation

the up-down dimension of sound localization

harmonic coherence

when frequencies present in the environment resemble the possible pattern of a fundamental frequency and higher harmonics

Inferior colliculus

a structure in the midbrain that receives input from the superior olive

Interaural level difference

the difference in loudness and frequency distribution between the two ears

interaural time difference

the time interval between when a sound enters one ear and when it enters the other ear

medial geniculate nucleus

a structure int he thalamus that receives auditory input from the inferior colliculus and sends output to the auditory cortex

Parabelt

a region of the auditory cortex, in addition to the belt area, that wraps around the auditory core regions

Primary auditory cortex

the first area in the auditory cortex, which receives input from the medial geniculate nucleus

rate of approach

the measure of whether a predator is approaching a target or receding from it

reverberation time

the difference between the onset of direct sounds and the first onset of indirect sound

Rostral core

an area int he auditory core region of the auditory cortex

Rostrotemporal core

an area, in addition to the rostral core, in the auditory core region of the auditory cortex

Spatial segregation

the process whereby sounds that are coming from the same location are grouped together, whereas sounds that are coming from different locations are not grouped together

Spectral segregation

the process whereby sounds that overlap in harmonic structure are grouped together, whereas sounds that do not overlap in harmonic structure are not grouped together

Spectral shape cue

the change in a sound’s frequency envelope created by the pinnae; it can be used to provide information about the elevation of a sound source

Superior olive

a structure int he brain stem thatt receives input from the inner hair cells and from the cochlear nucleus

target range

the distance of a predator from its potential target, determined by timing an echo’s return

temporal segregation

the process where by sounds that are linked in time are group together, whereas sounds that are not correlated with one another are not grouped together

Tonotopic organization

the organization of neurons within a region in the brain according to the different frequencies to which they respond

trapezoid body

a structure in the brain stem that plays a role in determining the direction of sounds