Lexico-semantics

This chapter presents a theoretical review of how humans represent and process word meaning (lexico-semantics). We start with a review of current theoretical approaches. The review is necessarily brief and incomplete but attempts to provide a cross-disciplinary perspective on word meaning informed by cognitive and developmental psychology, cognitive neuroscience, linguistics and computational sciences. We then move to a discussion of what we believe are core theoretical issues that ought to be addressed by any theory of lexical semantics. These key issues are: (1) whether and how we should distinguish between concepts and word meanings; (2) the format of lexico-semantic representations and (3) whether lexico-semantics should be considered as fundamentally context-independent or as context-dependent. We focus in particular on the issue of context-invariance vs. context dependency as we see this is as a core contemporary challenge that needs to be comprehensively addressed in order for the field to move forward. We define context as the conditions under which meaning is learnt and processed. At a minimum this includes the cognitive context (e.g. the prior knowledge of the individual, the learning history), the task context (e.g. language encountered before and after the word itself, what the individual is doing with the linguistic stimuli) and the physical context (e.g. co-occurring non-linguistic information such as perceived faces, gestures, environmental stimuli and so on). While there is a long-standing tradition that considers word meaning as dynamic, influenced by both linguistic and non-linguistic context and a large body of evidence showing context- effects on processing word meanings, very few attempts have been made at providing a systematic overview of what, when and how context matters in lexico-semantic processing