Dagbani language
Olawsky (1996) claims there is no vowel harmony in the Dagbani language. After Olawsky (1996), was Dakubu (1997), the first scholar to discover the possibility of vowel harmony in the language. Olawsky (1999), however, also later came to realise the possibility of vowel harmony in the language and studied it in-depth. Hudu (2010 & 2016) also later carried a thorough investigation of the phenomenon.
Dakubu (1997) discusses vowel harmony concerning the distribution of the triggers and targets in the syllable types. She did not pay much attention to the syllable domains, as in the root-to-suffix nor suffix-to-root harmony triggers. For instance, she explains how [-ATR] and [+ATR] vowels harmonise in CV and CVCCV and CVCVCV. She observes that depending on the suffix, several themes (the various syllables) fall under different harmony patterns; she states that the phenomenon in Dagbani is not different from that of Dagaare, Gurune, and Moore languages, see (Dakubu 1997:85). Dakubu interestingly states that [a] belongs to both sets of [ATR] in the language. Thus, [a] occurs with both [+ATR] and [-ATR] vowels (cf Dakubu 1997:84). Instances of the impact of vowel harmony have been captured in chapter seven. For example, root to suffix harmony helps explain the feature in RP quality, people, and couple in chapter seven.
Olawsky (1999) observes that the roots and suffixes play a vital role in vowel harmony in Dagbani. It is the case that ”the vowel of a suffix is generally realised according to the feature value for [ATR] in the root” Olawsky (1999:249). He presents the following as the various vowels
contained in the roots of words and the set of vowels in the suffix that follow them
[ATR] root vowel Harmoney