Neuropsychology and Past TenseVerb Inflection

Introduction
For the past couple of decades, the study of verb past tense has become a proving ground for two competing accounts of verb representation. Differences between these two theories are revealed in the manner in which they explain the processing of regular versus irregular verbs. In English, there are two broad classes of verbs distinguished by their inflectional morphology. Regular verbs, constituting the majority of verbs, form their past tense by adding the regular affixes /d/, /ed/, or /t/, depending on the stem. For example, “fix/fixed”, “rain/rained”, and “help/helped”. Therefore, a regular past tense verb is composed of its stem and the affix, such as “open-“ and “-ed” in “opened”. Such verbs are phonologically predictable since they all form their past tense in a standard way. On the other hand, the past tense of irregular verbs is inconsistent, and cannot be predicted by the stem. For example “hit/hit”, “run/ran”, “drive/drove”. ...