title: Shapes, scents and sounds: quantifying the full multi-sensory basis of conceptual knowledge.
abstract: Contemporary neuroscience theories assume that concepts are formed through experience in multiple sensory-motor modalities. Quantifying the contribution of each modality to different object categories is critical to understanding the structure of the conceptual system and to explaining category-specific knowledge deficits. Verbal feature listing is typically used to elicit this information but has a number of drawbacks: sensory knowledge often cannot easily be translated into verbal features and many features are experienced in multiple modalities. Here, we employed a more direct approach in which subjects rated their knowledge of objects in each sensory-motor modality separately. Compared with these ratings, feature listing over-estimated the importance of visual form and functional knowledge and under-estimated the contributions of other sensory channels. An item's sensory rating proved to be a better predictor of lexical-semantic processing speed than the number of features it possessed, suggesting that ratings better capture the overall quantity of sensory information associated with a concept. Finally, the richer, multi-modal rating data not only replicated the sensory-functional distinction between animals and non-living things but also revealed novel distinctions between different types of artefact. Hierarchical cluster analyses indicated that mechanical devices (e.g., vehicles) were distinct from other non-living objects because they had strong sound and motion characteristics, making them more similar to animals in this respect. Taken together, the ratings align with neuroscience evidence in suggesting that a number of distinct sensory processing channels make important contributions to object knowledge. Multi-modal ratings for 160 objects are provided as supplementary materials.
authors.affiliation: Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, Zochonis Building, University of Manchester, Oxford Road, Manchester M13 9PL, UK. paul.hoffman@manchester.ac.uk
authors.forename: Paul
authors.initials: P
authors.lastname: Hoffman
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Lambon Ralph
mesh_terms: D016000:Cluster Analysis; D003210:Concept Formation / Q000502:physiology*; D005260:Female; D006801:Humans; D019359:Knowledge; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010898:Pitch Perception; D011930:Reaction Time; D012044:Regression Analysis; D012660:Semantics; D012903:Smell / Q000502:physiology*; D013016:Sound; D014825:Vocabulary; D055815:Young Adult