Fundamental frequency	The lowest rate the vocal folds vibrate to produce a complex speech sound.
Hertz	An acoustic measure of the frequency of a complex speech sound in cycles per second that is usually the fundamental frequency. The first harmonic of a complex speech sound is usually one musical octave above the fundamental frequency or double the Hertz of the fundamental frequency. The second harmonic is usually one octave above the first harmonic or double the Hertz of the first harmonic. The third harmonic is double the Hertz of the second harmonic, etc.
Intonation	Manipulation of pitch over time
Lexical tones	Brief pitch contours associated with articulation of words in tone languages that are critical for word meaning.
Operculum	Region of the brain that surrounds the Sylvian fissure and overlies the insula.
Pitch	A psychoacoustic construct of how high or low a speech sound is perceived by a listener relative to a musical scale. Pitch is produced by vibrations of the vocal folds to produce a sound that has a fundamental frequency and various harmonics that are octave multiples.
Semitones	Converts Hertz to an acoustically logarithmic scale in which musical octaves (harmonics) are equally represented as a 12-semitone change in perceived pitch.