Secondary auditory cortex (planum temporale) lying behind Heschl’s gyrus at the rear of the left temporal lobe; regulates language comprehension. Also posterior speech zone.

Receptor surface in the cochlea that transduces sound waves into neural activity.

Measure of the relative physical intensity of sounds.

Asymmetrical structures within Heschl’s gyrus in the temporal lobes; receive input from the ventral region of the medial geniculate nucleus.

Speech production region on the left frontal lobe dorsal surface.

Major thalamic region concerned with audition.

Melodic tone of the speaking voice.

Inner ear structure containing the auditory receptor cells.

Inability to speak or comprehend language despite the presence of normal comprehension and intact vocal mechanisms. Broca’s aphasia is the inability to speak fluently despite the presence of normal comprehension and intact vocal mechanisms. Wernicke’s aphasia is the inability to understand or to produce meaningful language even though word production remains intact.

Spontaneous or evoked sound waves produced within the ear by the cochlea and escape from the ear.

Stimulus intensity; in audition, roughly equivalent to loudness, graphed by the increasing height of a sound wave.

Specialized neurons in the cochlea tipped by cilia; when stimulated by waves in the cochlear fluid, the cilia bend and generate graded potentials in inner hair cells, the auditory receptor cells.

Number of cycles a wave completes in a given time.

Electronic device implanted surgically into the inner ear to transduce sound waves to neural activity and allow a deaf person to hear.

Tone deafness—inability to distinguish between musical notes.

Multifunctional cortical tissue located within the lateral fissure; contains language- and taste perception–related regions and neural structures underlying social cognition.

Bone of the middle ear; includes malleus (hammer), incus (anvil), and stapes (stirrup).

Localization of function primarily on one side of the brain.

Identifying and locating an object by bouncing sound waves off it.

In audition, structural organization for processing of sound waves from lower to higher frequencies.

Anterior left hemisphere speech area that functions with the motor cortex to produce movements needed for speaking.

Measure of sound wave frequency (repetition rate); 1 hertz equals 1 cycle per second.

Mechanical displacement of molecules caused by changing pressure that possesses the physical properties of frequency, amplitude, and complexity. Also compression wave.