We instinctively know whether something is natural, or a synthetic mimic. But the key factors responsible for this perception have yet to be identified: this is the primary objective of this inter-disciplinary project. The perception of naturalness is dominated, in most cases, by visual appearance and touch. Basic visual sensory information, such as colour and gloss, and other visual triggers, such as shape and size (all mediated by photoreceptors in the retina) is often sufficient to differentiate between natural and synthetic materials. Touching the material serves to reinforce the initial visual perception: here tactile information from cutaneous pressure sensitive and thermal sensory transducers, as well as kinesthetic data, provides the requisite sensory input. This project aims to understand how these sensory data streams are processed by the relevant neural networks and how they contribute to the cognitive processes associated with the perception of naturalness. This understanding will take account of the effect of contextual information on this perception (i.e. the interplay between the individual senses and the relationship between the material and its environment).