Levels of processing in speech production.

Abstract

When subjects repeated short alphabetic sequences at experimenter-controlled rates while retaining consonant trigrams, subsequent recall was unrelated to speech rate if single letters or a long sequence was repeated, but recall was inversely related to speech rate for sequences three or five letters in length. The latter effect was predicted by a model in which sequences were organized as single response units in a central phonetic processor but independently executed by means of mechanisms not requiring the services of the central processor. Quantitative predictions were generated from this model by estimating organization time for the sequences and assuming that the probability of forgetting would be equal to the organization time/execution time ratio. All obtained recall probabilities were as predicted for sequences three of five letters in length with both experimenter- and subject-controlled speech rates. Repetition of a nine-letter sequence from the end of the alphabet produced forgetting patterns clearly out of accord with any organization time/execution time ratio, but a similar sequence from the beginning of the alphabet produced evidence of being a marginal case with unstable organization.

Memory representation of alphabetic position and interval information.

“…The terminal bend occurred at W (23rd letter) for both conditions, indicating a smaller range of serial search toward the end of the alphabet than at the beginning. This result is remarkably similar to one obtained by Aldridge (1981), where the results suggested that the longest spoken, alphabetic sequence that could be organized into a single utterance was limited by the capacity of STM. Evidence suggested that the maximum stable sequence from the beginning of the alphabet would be A through H but the maximum sequence from the end of the alphabet would be shorter, approximately V through Z.…”

Adapting to processing demands in discourse production: The case of handwriting.

“…A second reason is that the studies of speech production that have considered attention demands have argued mainly from hesitations and slips of the tongue observed in spontaneous speaking (see Bock, 1982; Clark & Clark, 1977; Dechart & Raupach, 1980; Fodor, Bever, & Garrett, 1974; Foss & Hakes, 1978; Gee & Grosjean, 1983; Goldman-Eisler, 1968; Levin, Silverman, & Ford, 1967). Examination of interference in concurrent task situations has been relatively rare (for exceptions, see Aldridge, 1981; Ford & Holmes, 1978), as have studies of response to stress for speed versus accuracy (see MacKay, 1982). And few, if any, speech production studies have looked at the combined effects of such factors manipulated simultaneously.…”