The accurate classification of psychophysiological data is an important determinant of the quality when interacting with a physiological computing system. Previous research has focused on classification accuracy of psychophysiological data in purely mathematical terms but little is known about how accuracy metrics relate to users' perceptions of accuracy during real-time interaction. A group of 14 participants watched a series of movie trailers and were asked to subjectively indicate their level of interest in a binary high/low fashion. Psychophysiological data (EEG, ECG and SCL) were used to create a binary classification of interest via a Support Vector Machine (SVM) algorithm. After a period of training, participants received real-time feedback from the classification algorithm and perceptions of accuracy were assessed. The purpose of the study was to compare mathematical classification accuracy with the perceived accuracy of the system as experienced by the users. Results indicated that perceived accuracy was subject to a number of psychological biases resulting from expectations, entrainment and development of trust. The F1 score was generally a significant predictor of perceived accuracy.

The prospect of connecting the brain and body to a technological device can elicit a broad range of responses from potential users. Early adopters are thrilled by the possibility of a device that can interface directly to the human nervous system. For the vast majority, interest is tempered by caution, as nascent varieties of physiological computing systems raise as many questions as answers about how we will interact with computers in the future.

This article presents a psychophysiological construct of interest as a knowledge emotion and illustrates the importance of interest detection in a cultural heritage context. The objective of this work is to measure and classify psychophysiological reactivity in response to cultural heritage material presented as visual and audio. We present a data processing and classification framework for the classification of interest. Two studies are reported, adopting a subject-dependent approach to classify psychophysiological signals using mobile physiological sensors and the support vector machine learning algorithm. The results show that it is possible to reliably infer a state of interest from cultural heritage material using psychophysiological feature data and a machine learning approach, informing future work for the development of a real-time physiological computing system for use within an adaptive cultural heritage experience designed to adapt the provision of information to sustain the interest of the visitor.

The biocybernetic loop describes the data processing protocol at the heart of all physiological computing systems. The loop also encompasses the goals of the system design with respect to the anticipated impact of the adaptation on user behaviour. There are numerous challenges facing the designer of a biocybernetic loop in terms of measurement, data processing and adaptive design. These challenges are multidisciplinary in nature spanning psychology and computer science. This paper is concerned with the design process of the biocybernetic loop. A number of criteria for an effective loop are described followed by a six-stage design cycle. The challenges faced by the designer at each stage of the design process are exemplified with reference to a case study where EEG data were used to adapt a computer game.