Development of Tests to Evaluate the Sensory Abilities of Children with Autism Spectrum Disorder using Touch and Force Sensors M. Riederer, C. Schoenauer, H. Kaufmann Institute of Software Technology and Interactive Systems Vienna University of Technology, Vienna, Austria {riederer, schoenauer, kaufmann}@ims.tuwien.ac.at E. Soechting, C. Lamm Department of Basic Psychological Research University of Vienna, Vienna, Austria {a8102373, claus.lamm}@unet.univie.ac.at Fig. 1. The newly developed instruments in action: measuring proprioceptive functions in children a) Grading of Force Test, b) Display of data on mobile device, c) Grading of Movement Test Abstract—An emerging line of research that attempts to reveal underlying mechanisms of Autism Spectrum Disorder (ASD) studies differences in sensory processing in individuals with ASD. In this paper, we introduce new methods to measure proprioceptive functions of children with ASD. The instruments use a low-cost Arduino board and shield to acquire data from force and touch sensors. Data are transferred to mobile devices and analyzed with cross-platform application development tools. The instruments were pilot tested with typically developing children to test for functionality and usability of the instruments. They will be used in a larger study with children with ASD. Keywords–autism spectrum disorder; proprioception; pervasive computing; mobile healthcare; wireless sensors I. INTRODUCTION Autism Spectrum Disorder (ASD) is a pervasive developmental disorder with an average prevalence of less than one percent [1]. It is characterized by impairments in social, communication and behavioral skills. Many countries prioritize autism research in order to better understand the causes and mechanisms of this disorder and to develop more specific and causal treatments compared to the dominating symptomatic approach of behavior modification. One line of research explores the sensory processing and sensorimotor differences in individuals with ASD [2, 3]. Differences in sensory processing and multisensory integration have been widely reported. Most of these studies used indirect measures such as parent questionnaires (e.g., the Sensory Profile [4]) for data collection. Novel test instruments that allow for direct measurement are warranted to substantiate these reports by “hard” objective data. Outcomes of this project could be translated into clinical applications (e.g., early detection of sensory processing disorders, focus of early intervention on underlying mechanisms). One sensory system that has not been studied thoroughly is the proprioceptive sense. The proprioceptive sense carries information from receptors in muscles and joints. The primary source of proprioception is active muscle contraction. Proprioceptive information is used for regulation of tone and postural control, action model formation, motor planning and control, and behavioral organization [5].„Given the importance of proprioception for even the most basic motor behaviors, directly examining proprioceptive processing in individuals with ASD is crucial for understanding the underlying causes of the social, communicative, and motor impairments.“ [6] Our contributions to the field are:  Design of tests and test instruments for objective assessment of proprioceptive functions.  Implementation of a mobile low-cost system integrating these tests with sensors and mobile devices (see Fig. 1).  Evaluation of the system's functionality und usability with typically developing subjects. II. MEDICAL BACKGROUND AND RELATED WORK Numerous studies have provided evidence that individuals with ASD process and use proprioceptive information differently (see [6], for an overview). Haswell et al. [7], found that children with ASD rely more on proprioceptive information to learn motor tasks. Only one study [6] investigated the type of sensory processing deficit that may impair effective use of proprioceptive information in autism. The findings of this study suggested that no primary proprioceptive deficits caused the motor impairment but maybe deficits at later processing states. This study used mostly passive tasks to measure proprioception. A new paradigm for examining proprioceptive processing at different processing stages that uses active muscle contraction may refine our understanding of the role of proprioception in autism.