Semiosis of visual stimuli in interactive user interfaces of medical applications

The problem of achieving completeness and unity of objective, subjective, and virtual reality is considered in relation to the applied tasks of designing interactive user interfaces. Within the framework of constructing an immersive environment using modern information technologies, the problem of forming an ontology of perception is investigated. The key role of a sign in information interaction is highlighted, taking into account the individual characteristics of its perception by users of virtual reality. In an immersive environment, virtual signs can be embodied both as observable objects with varying degrees of realism and directly in the form of signs, both graphic and text, that have a specific location in space. The proposed approach allows for setting an algorithm for visual impact on a person by dynamically forming a sequence of signs. The formed sequences create a queue of visual stimuli that adjust the tempo-rhythm of the user's interaction with the computer system. The signs observed by the user can be classified as iconic signs corresponding to conventional symbols or pictograms, index signs acting as pointers to other objects and marking space for orientation purposes, and symbolic signs signaling or warning about changes in an object, event, or phenomenon. The article considers test examples of user behavior in a virtual reality environment. The proposed approach is implemented in a software system for psychological diagnostics and rehabilitation. A special feature of the system is the control of patient involvement based on the analysis of the dynamics of head movements, facial movements, and gaze trajectory using artificial neural networks. In case of distraction or loss of interest, the computer system adapts the user interface by adding visual stimuli according to specified pragmatic rules. The application of the obtained results has enabled the adaptation of the user interface and created the possibility for a personalized approach to the provision of medical services.