Taking some lungfuls of icy sea air over the weekend made me think about speech sounds and what West African specialities there are among them. Plain vanilla speech sounds tend to be produced with a pulmonic egressive air stream, that is, with air being exhaled from the lungs. Some speech sounds are formed by forming an obstacle somewhere in the mouth that is then released, first increasing the air pressure behind the closure, then releasing it, pushing the air outwards. Try it with a [b]. Your lips form an obstruction, air pressure builds behind your them, and when it is released, air leaves your mouth. But a much rarer class of speech sounds, so-called implosives, bears this name because supposedly, the glottis is lowered and causes negative air pressure, before the air is subsequently released outwards, causing some air to be initially sucked inwards. Hence the word implosive.
You can listen to an implosive in Owerri Igbo here. Now try it youself: say [b] again, but this time lower your glottis. Implosive consonants are written with a rightward little hook on the letter – you’ve seen them in some Fula words in previous posts in this blog, for instance in the one on bards, which featured the word lawɓe ‘woodworkers’. [ɓ] is the implosive counterpart of [b]. Voiced implosives are quite common; voiceless ones (formed without the vocal cords vibrating) are extremely rare. Seereer languages, spoken in Senegal, are among the languages that have both voiced and voiceless implosives, but only one variety of the language, Seereer Siin, has words that are only distinguished through having a voiced vs. a voiceless implosive. Have a look:
What makes these sounds even more intriguing is that in many languages they aren’t actually produced by negative air pressure forming behind an obstruction at all. Rather, what distinguishes them from explosive stops is that there is no positive air pressure involved, just absence of air pressure – silence. So strictly speaking, ‘implosive’ is a misnomer for this type of sound. There’s much more to be said about implosives in Seereer, but I leave you to discover it by yourself!
You can find an overview of phonetic research on implovises in Seereer and an acoustic phonetic study of implosives in Seereer Siin here: