What is the most basic frequency measure perceived as pitch in speech?

The most basic frequency measure perceived as pitch in speech is fundamental frequency (Fo). This frequency refers to the lowest frequency of a periodic waveform and is crucial in determining the pitch of a person's voice. In speech, the fundamental frequency usually correlates with how high or low a voice sounds to listeners.

Fundamental frequency is primarily controlled by the rate of vocal fold vibration during phonation; a faster vibration results in a higher pitch, whereas a slower vibration produces a lower pitch. This is why Fo is often directly associated with the perceived pitch of speech sounds.

Understanding fundamental frequency is essential for various aspects of speech science, including voice disorders, intonation patterns in speech, and the emotional tone conveyed through voice. It serves as a foundational concept for further exploring other frequency-related measures in speech, such as formant frequencies, which are important for distinguishing vowel sounds but are not directly responsible for pitch perception.