From Amodal to Grounded to Hybrid Accounts of Knowledge: New Evidence from the Investigation of the Modality-Switch Effect

My dissertation sets out to contribute to the ongoing theoretical debate on the format of conceptual representation from both a theoretic (Part 1) and an experimental point of view (Part 2). From a theoretic point of view, it is attempted to show that the amodal and grounded views do not bear incompatible claims. On the contrary, grounded cognitition has complemented traditional approaches taking into account the modalities, the body, and the environment’s influence on cognitive mechanisms. From an experimental point of view, this dissertation is committed to testing predictions coming from grounded accounts of knowledge. Specifically, it is aimed at verifying the assumption that modality-specific representations underlie concepts and conceptual processing through the investigation of the Modality-Switch Effect, a cost for performance in terms of speed and accuracy occurring when two different sensory modality properties for concepts alternate compared to when the same sensory modality property is presented. Four experiments were conducted. Experiments 1 & 2 (Study 1) allowed the author to demonstrate that the Modality-Switch Effect is an automatic robust effect arising during both reading and speech processing. Experiments 3 & 4 (Study 2) assessed the impact of the mode of presentation of stimuli (i.e., visual: through the monitor, aural: through a pair of headphones) on the conceptual Modality-Switch Effect. It is shown that the mode of presentation effect weakens the conceptual Modality-Switch Effect in both a property verification and a lexical decision priming paradigms. In sum, the extensive analysis of amodal and grounded views taken together with the innovative findings reported in this dissertation led the author to suggest that hybrid approaches, that combine aspects of both views, should be preferred over the amodal-only and grounded-only accounts.