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 the production of words is still intact.
Intensity of a stimulus; in audition, roughly equivalent to loudness, graphed by increasing the height of a sound wave.
supplementary speech area
Speech-production region on the dorsal surface of the left frontal lobe.
Bones of the middle ear: malleus (hammer), incus (anvil), and stapes (stirrup).
Inner-ear structure that contains the auditory receptor cells.
Number of cycles that a wave completes in a given amount of time.
Measure of frequency (repetition rate) of a sound wave; 1 hertz is equal to 1 cycle per second.
Electronic device implanted surgically into the inner ear to transduce sound waves into neural activity and allow a deaf person to hear.
Ability to identify and locate an object by bouncing sound waves off the object.
Process whereby functions become localized primarily on one side of the brain.
medial geniculate nucleus
Major thalamic region concerned with audition.
primary auditory cortex (area A1)
Asymmetrical structures, found within Heschl's gyrus in the temporal lobes, that receive input from the ventral region of the medial geniculate nucleus.
Property of audition in which sound waves are processed in a systematic fashion from lower to higher frequencies.
Unit for measuring the relative physical intensity of sounds.
Sensory neurons in the cochlea tipped by cilia; when stimulated by waves in the cochlear fluid, outer hair cells generate graded potentials in inner hair cells, which act as the auditory receptor cells.
Receptor surface in the cochlea that transduces sound waves into neural activity.
Tone deafness - an inability to distinguish between musical notes.
Anterior speech area in the left hemisphere that functions with the motor cortex to produce the movements needed for speaking.
Melodical tone of the spoken voice.
Located within the lateral fissure, multifunctional cortical tissue that contains regions related to language, to the perception of taste, and to the neural structures underlying social cognition.
Secondary auditory cortex (planum temporale) lying behind Heschl's gyrus at the rear of the left temporal lobe that regulates language comprehension; also called posterior speech zone.
Undulating displacement of molecules caused by changing pressure.