ABSTRACT
Learning the past tense of English verbs has become a landmark task for testing the adequacy of cognitive modeling. We review a set of intriguing psychological phenomena that any modeling of past-tense acquisition has to account for. Traditional grammatical theories fail to explain phenomena of irregular verbs, while connectionist models, which require no symbols and explicit rules, fail on regular verbs. We present a general-purpose symbolic pattern associator (SPA for short) which learns a set of sufficient and necessary symbolic rules for both distinguishing and predicting regular and irregular verbs. Our all-rule theory is similar in spirit to Pinker’s (1991, 1993) modular hypothesis, and is able to account for most psychological phenomena in past-tense acquisition. Even on the task of irregular past-tense generalization, the SPA is judged to be slightly more plausible than the connectionist model by adult native English speakers. Our results support the view that language acquisition and processing should be better modeled by symbolic, rather than connectionist, systems.
