Vocal Hiccup

Physiology

1. A rapid inhalation under closed vocal chords. Without exhaling, the vocal chords are released just enough for them to vibrate under that inhalation, thus creating the sound. The phonation can also be thought of as an extreme reverse vocal fry.
2. (hiccup): an involuntary spasm of the diaphragm and respiratory organs, with a sudden closure of the glottis and a characteristic sound like that of a cough.Garcia, Ramos J, and Solorio A Cobian. “On the glottal activity of experimental hiccup.” -Dictionary
3. It is a fake hiccup or short stylistic intake of air. -Wikipedia on “Vocal Hiccup”
4. The act of tensing your stomach and gasping for air at the same time.  -Answers.com

Music

The vocal technique is most notably credited to Michael Jackson, and it is referred to by the pop culture community as his “signature.” It is a creative phonation similar to reverse vocal fry. It’s purpose is to add a percussive element between phrases of a song, as well as an emotional intensity.

One Critic of Music describes it this way: “[Michael Jackson’s] vocal ‘hiccups’ (somewhat like gulping for air or gasping) and breathless stutters were legendary. His grunts were achieved with good technique, and added to an already impressive vocal delivery.