In network models, the learning of static combinations of the same linguistic units (syllables, morphemes) leads to the formation of distributed neuronal assemblies (DNAs) for these elements of a “lexicon”. In contrast, the learning of flexible combinations between words from specific lexical-semantic categories sets up indirect links by way of circuits we call combinatorial neuronal assemblies (CNAs), which may realize aspects of a “grammar”. DNAs and CNAs motivate the proposal of distinct neurobiological mechanisms for combining meaningful elements into strings, one for whole form storage of static complex-lexical elements and fixed constructions, with distinct brain signatures. Consistent with this model, we found different neurophysiological signatures for violations of static-lexical and flexible-grammatical predictions, These signatures may be useful for addressing questions in linguistics and brain science.
A fundamental distinction in linguistic theory is made between stored lexical entries and rules or s chemes that flexibly combine these elements. Recent proposals extend the range of lexical entries to the level above the word, also allowing con structions of several words to become unitary constructions (UCs) in the lexicon. Correspondingly, flexible combinatorial schemes (CSs) also operate at the level below the word; morphological rules similar to the rules of syntax govern the composition of m orphemes into complex words. Whether a given compl ex linguistic form is seen as a stored element or as a composed, assembled one is typically decided on the basis of semantic and combinatorial criteria. Recent research has indicated that biolinguistic crit eria can speak to this issu e, possibly leading to a clarification of the lexical / combinatorial status of an expression based on neurophysiological data recorded directly from the human brain.This project used neurophysiology to track the brain basis of lexical storage vs. flexible combination.It also investigated complex forms, whose status as either stored or cominatorially-assembled is still under debate.