Widgets: A new set of parametrically defined 3D objects for use in haptic and visual categorization tasks

Introduction. - Most research to date on human categorization ability has concentrated on the visual and auditory domains. However, a limited - but non-negligible - range of studies has also examined the categorization of familiar or unfamiliar (i.e., novel) objects in the haptic (i.e., tactile-kinesthetic) modality.Objective. - In this paper, we describe how we developed a new set of parametrically defined objects, called widgets, that can be used as 3D (or 2D) materials for haptic (or visual) categorization purposes.Method. - Widgets are unfamiliar complex 3D shapes with an ovoid body and four types of elements attached to it (eyes, tail, crest, and legs). The stimulus set comprises 24 objects divided into four categories of six exemplars each (the files used for 3D printing are provided as Supplementary Material).Results. - We also assessed and demonstrated the validity of our stimulus set by conducting two separate studies of haptic and visual categorization, involving participants of different ages: young adults (Study 1), and children and adolescents (Study 2). Results showed that humans can categorize our 3D complex shapes on the basis of both haptically and visually perceived similarities in shape attributes.Conclusion. - Widgets are very useful new experimental stimuli for categorization studies using 3D printing technology. (C) 2020 Elsevier Masson SAS. All rights reserved.