The psychological reality of hidden lexical entries. Evidence from Hebrew

In this paper I discuss hidden lexical entries: forms that are assumed to be represented in the mental lexicon even though they do not exist in the actual vocabulary, in order to account for derivational gaps. This mechanism is often criticized to be an ad-hoc, unfalsifiable theoretical tool and to lack psychological reality. I argue that in view of the commonly assumed interface between the mental lexicon and the conceptual system, hidden lexical entries are not unfalsifiable. To demonstrate this argument, I present an experiment designed to detect the hidden existence of gaps in the transitive-unaccusative alternation.