Speech Errors

Speech Errors
Most of us make similar errors from time to time. Although some errors are not common, all speakers seem to make them occasionally. Some people are prone to speech errors than others. The scientific analysis of speech errors is called “slips of the tongue”. Researchers use speech errors to examine the role of linguistic units in the production of speech.
Although speech errors cover a wide range of semantic content, there seems to be only a small number of basic types. Those types of errors occur with a number of linguistic units. In some cases, a single phoneme is added, deleted or moved, but sometimes it may be sequence of phonemes, morphemic affixes and roofs, whole words or even phrases. As a general rule, errors tend to occur at only one linguistic level per utterance. That is, when a person clearly says the wrong word, the sentence is syntactically and phonologically intact.
Speech errors appear with four generalizations. First., elements that interact with one another tend to come from similar linguistic environments. For example, sentence (1) “You are pig and fat (or tig and fab ).(big and fat)” and sentence (2) “Don’t interfere with my nife lite. (night life)” We notice that the phonetic segments in the beginn ing of a word tend to be exchanged with initial segments. The same is true for middle and final segments. Moreover, exchanges of segments are more common when the segments that precede them are similar. The exchange of |f| and |t| in sentence (2) follows this principle.
Second, elements that interact with one another tend to be similar to one another. In particular, consonants are invariably exchanged or shifted with other consonants but not with vowels, such as in sentence (1). Errors involving similar sounds often have little relation to meaning but relate to phonetic similarity, such as in this sentence “Sesame Street
crackers” (sesame seed crackers). (Fromkin, 1973)
Third, when slips produce novel linguistic items, they are usually consistent with the phonological rules of the language. For example, an error like “slickery” (for slick and slippery) occurs, while other phonologically similar forms, such as “slickppery” and “ slipkery” do not occur.
Finally, there are consistent stress patterns in speech errors. Segments that are exchanged for one another both receive major stress in the word or phrase in which reside, or both receive minor stress.
Therefore, speech errors are hardly random. Actually they occur in highly regular patterns. However, why will they occur? Anecdotal evidence indicates that speech errors are more common when we are nervous or under stress, as when performers appear on live television and radio shows. Errors are more likely to occur when we are tired, anxious or drunk. According to the theory of Freud, “slips of the tongue” is important, because like dreams, they help to reveal the unconscious mind. Errors occur because we have more than a single plan for production and that one such plan competes with and dominates the other. Although a Freudian type of explanation may apply to some speech errors, more recent thinking has focused on the psycholinguistic process underlying speech errors. That is, the insight can be gained in understanding language mechanism from the study of speech errors.
Generally we produce speech through a series of separate stages, each devoted to a single level of linguistic analysis. Errors occur at one level, but not others, during the production process.
References:
(1) Psycholinguistics, Thomas Scovel , 上海外语教育出版社
(2) Psychology of language, Third edition, David W. Carroll, 外语教学与研究出版社。