Phonology - Analysis of Phonemes

Analysis of Phonemes

An important part of traditional, pre-generative, schools of phonology is studying which sounds can be grouped into distinctive units within a language; these units are known as phonemes. For example, in English, the "p" sound in pot is aspirated (pronounced ), while that in spot is not aspirated (pronounced ). However, English speakers intuitively treat both sounds as variations (allophones) of the same phonological category, that is, of the phoneme /p/. (Traditionally, it would be argued that if a word-initial aspirated were interchanged with the unaspirated in spot, native speakers of English would still hear the same words; that is, the two sounds are perceived as "the same" /p/.) In some other languages, however, these two sounds are perceived as different, and they are consequently assigned to different phonemes in those languages. For example, in Thai, Hindi, and Quechua, there are minimal pairs of words for which aspiration is the only contrasting feature (two words with different meanings that are identical except that one has an aspirated sound where the other has an unaspirated one).

Part of the phonological study of a language therefore involves looking at data (phonetic transcriptions of the speech of native speakers) and trying to deduce what the underlying phonemes are and what the sound inventory of the language is. The presence or absence of minimal pairs, as mentioned above, is a frequently used criterion for deciding whether two sounds should be assigned to the same phoneme. However other considerations often need to be taken into account as well.

The particular sounds which are phonemic in a language can change over time. At one time, and were allophones in English, but these later changed into separate phonemes. This is one of the main factors of historical change of languages as described in historical linguistics.

The findings and insights of speech perception and articulation research complicates the traditional and somewhat intuitive idea of interchangeable allophones being perceived as the same phoneme. First, interchanged allophones of the same phoneme can result in unrecognizable words. Second, actual speech, even at a word level, is highly co-articulated, so it is problematic to expect to be able to splice words into simple segments without affecting speech perception.

Different linguists therefore take different approaches to the problem of assigning sounds to phonemes. For example, they differ in the extent to which they require allophones to be phonetically similar. There are also differing ideas as to whether this grouping of sounds is purely a tool for linguistic analysis, or reflects an actual process in the way the human brain processes a language.

Since the early 1960s, theoretical linguists have moved away from the traditional concept of a phoneme, preferring to consider basic units at a more abstract level, as a component of morphemes; these units can be called morphophonemes, and analysis using this approach is called morphophonology.