Conceptual and Grammatical Fields: Speech Errors Revisited

This paper reports a study of the effects of semantic and grammatical interference basing on the analysis of about 300 Russian speech errors (slips of the tongue) of two kinds: contextual semantic substitutions (when a word semantically related to a distractor word from the current sentence is substituted for the target word) and contextual substitutions of a grammatical feature such as case, number, gender and person, resulting from the interference of a grammatical feature of an "interloper" (a distractor word form from the current sentence, either preceding or following the target word). Contextual semantic substitutions demonstrate the effect of lexical retrieval failure due to the semantic interference of another word from the current utterance, e.g.: U nas taburetka na kuxne -> U nas taburetka na stule We have a stool in the kitchen -> We have a stool in the chair [The word stule 'chair' is selected instead of the target noun kuxne 'kitchen' due to the semantic interference of the word taburetka 'stool'.] The semantic interference effect is assumed to result from competition among lexical nodes during lexical retrieval. The distractor word spreads activation to semantically related lexical nodes, which begin to compete with the target lexeme node. If a node semantically related to the distractor word is more highly activated, it may be selected instead of the target word. Not surprisingly, phonological similarity seems to augment the semantic interference effect. Once the lexical node is selected, there is another process responsible for the selection of the word's grammatical features. Contextual substitutions of a grammatical feature indicate that grammatical features, like lexical nodes, can also compete for selection, e.g.: Ja ne javljajus? specialistom po igr-e na klarnet-e I not am specialist in playing-SG.F.DAT clarinet-SG.M.LOC -> Ja ne javljajus? specialistom po igr-e na klarnet-u I not am specialist in playing-SG.F.DAT clarinet-SG.M.DAT I am not a specialist in playing the clarinet [The dative case form of the noun klarnet 'clarinet' is substituted for the target locative case form due to the interference of the dative case feature of the noun igre 'playing'.] The grammatical encoding mechanism has to decide which grammatical form of the target word to select. Due to the intrusion of a distractor word form, which activates an irrelevant grammatical feature, the process of grammatical encoding can derail, and the irrelevant feature can overwrite the target feature. In Russian (a highly inflected language), such derailment will usually surface as a wrong inflection suffixed to the lexical stem of the target word. This account contradicts the view that the selection of grammatical features is an automatic consequence of lexical selection. To summarize, speech error data demonstrate pervasive within-speaker interference of both word meanings and grammatical features throughout the sentence production process, indicating that the process is generally competitive. A way to account for the interference effects is to suggest that alongside its conceptual field, a word form activates a field of its grammatical features, spreading activation to other words within the current sentence.