Implicature Processing

In natural language, what speakers communicate is often far richer than what they overtly express. Implicatures are a paradigm case of meaning emerging beyond what is strictly said: they are inferences through which language users enrich the literal meaning of utterances (e.g., “Some guests were satisfied”) and derive additional meaning (“Some, but not all guests were satisfied”). This dissertation addresses several key issues regarding implicature processing: the production-comprehension asymmetry emerging in acquisition, the role of socio-cognitive factors, the role of language proficiency, and the effort involved in the derivation. These issues are explored from a theoretical and empirical perspective. First, to account for the production-comprehension asymmetry, a theoretical model of implicature acquisition is developed. The second part of the dissertation reports on four experimental studies: one with children, one with second-language speakers, one with adults from the general population, and one with autistic adults. The latter two test implicature processing using pupillometry, a psychophysiological measure of effort allocation. Overall, implicatures emerge as a form of non-automatic pragmatic enrichment. The empirical findings reveal that implicatures are associated with a cognitive cost, which is influenced by autistic traits. Moreover, the tendency to overaccept literal meaning is modulated by language proficiency, but not by individuals’ socio-cognitive profiles. The dissertation contributes to the ongoing debate regarding the nature of implicature, a phenomenon that, being at the interface between language, reasoning, and metacognition, represents a unique window into the human cognitive system.