The phonetic basis of a phonological pattern

Prenasalized voiced consonants demonstrate an unusual phonologization pattern: in some languages, they have phonologized their depressor effects (the reliable lowering of pitch on a following vowel) — that is, they always coincide with low-tone syllables, while in other languages they have not. The potential origins of this pattern are hard to determine without data on the intrinsic phonetic effects of prenasalized segments on F0. This study reports data on consonant-F0 interaction in Chichewa, a language with prenasalized segments in both high tone and low tone segments, in order to measure these effects in an environment where depressor effects have not been phonologized. The data suggests that the intrinsic phonetic effects of prenasalized consonants fall somewhere between the effects of plain stops and those of plain nasals, positioning these prenasalized segments to pattern either as depressors or as non-depressors, depending on language-specific conditions.