Modelling the effects of semantic ambiguity in word recognition

Jennifer M. Rodd, M. Gareth Gaskell, William D. Marslen‐Wilson

Cognitive Science · 2004 · 220 citations · 24 references

Concepts

TL;DR

Most English words are ambiguous, having multiple meanings that vary by context. The study examines how different kinds of semantic ambiguity affect connectionist models of word recognition. The model implements competition among distributed semantic representations to resolve ambiguity. The model accurately retrieves meanings of ambiguous words, reproduces lexical‑decision effects, shows a disadvantage for words with unrelated multiple meanings due to interference, a benefit for words with related senses linked to attractor‑basin structure, and supports the view that word meanings are stable states in a high‑dimensional semantic space shaped by sense variation. Published in Journal of Memory and Language, 2002.

Abstract

Abstract Most words in English are ambiguous between different interpretations; words can mean different things in different contexts. We investigate the implications of different types of semantic ambiguity for connectionist models of word recognition. We present a model in which there is competition to activate distributed semantic representations. The model performs well on the task of retrieving the different meanings of ambiguous words, and is able to simulate data reported by Rodd, Gaskell, and Marslen‐Wilson [J. Mem. Lang. 46 (2002) 245] on how semantic ambiguity affects lexical decision performance. In particular, the network shows a disadvantage forwords with multiple unrelated meanings (e.g., bark) that coexists with a benefit for words with multiple related word senses (e.g., twist). The ambiguity disadvantage arises because of interference between the different meanings, while the sense benefit arises because of differences in the structure of the attractor basins formed during learning. Words with few senses develop deep, narrow attractor basins, while words with many senses develop shallow, broad basins. We conclude that the mental representations of word meanings can be modelled as stable states within a high‐dimensional semantic space, and that variations in the meanings of words shape the landscape of this space.

References

24