Lexical configuration and lexical engagement: when adults learn new words

Abstract

People know thousands of words in their native language, and each of these words must be learned at some time in the person's lifetime. A large number of these words will be learned when the person is an adult, reflecting the fact that the mental lexicon is continuously changing. We explore how new words get added to the mental lexicon, and provide empirical support for a theoretical distinction between what we call lexical configuration and lexical engagement. Lexical configuration is the set of factual knowledge associated with a word (e.g., the word's sound, spelling, meaning, or syntactic role). Almost all previous research on word learning has focused on this aspect. However, it is also critical to understand the process by which a word becomes capable of lexical engagement--the ways in which a lexical entry dynamically interacts with other lexical entries, and with sublexical representations. For example, lexical entries compete with each other during word recognition (inhibition within the lexical level), and they also support the activation of their constituents (top-down lexical-phonemic facilitation, and lexically-based perceptual learning). We systematically vary the learning conditions for new words, and use separate measures of lexical configuration and engagement. Several surprising dissociations in behavior demonstrate the importance of the theoretical distinction between configuration and engagement.

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Experiment 1: Phoneme monitoring reaction times and accuracy

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Experiment 1: Three alternative forced choice recognition accuracy

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Experiment 1: Threshold task, average noise level and average accuracy for recognizing items in noise

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Experiment 1: Perceptual learning task, averaging labeling as “sh”, for groups who would have enlarged the “sh” category (solid line) or the “s” category (dashed line)

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Experiment 2: Pictures that were assigned to the 12 new words

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Experiment 2: Response times and accuracy for selecting pictures

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Experiment 2: Threshold task, average noise level and average accuracy for recognizing items in noise

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Experiment 2: Perceptual learning task, averaging labeling as “sh”, for groups who would have enlarged the “sh” category (solid line) or the “s” category (dashed line)

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Experiment 3: Perceptual learning task, averaging labeling as “sh”, for groups who would have enlarged the “sh” category (solid line) or the “s” category (dashed line)

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Experiment 4: Threshold task, average noise level and average accuracy for recognizing items in noise

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Experiment 4: Perceptual learning task, averaging labeling as “sh”, for groups who would have enlarged the “sh” category (solid line) or the “s” category (dashed line)

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Experiment 5: Perceptual learning task, averaging labeling as “sh”, for groups who would have enlarged the “sh” category (solid line) or the “s” category (dashed line)

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Experiment 5: Threshold task, average noise level and average accuracy for recognizing items in noise

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Between experiment comparison of threshold task performance