Brain and Body Interfaces: Designing for Meaningful Interaction Abstract The brain and body provide a wealth of information about the physiological, cognitive and emotional state of the user. There is increased opportunity to use these data in computerised systems as forms of input control. As entry level physiological sensors become more wide- spread, physiological interfaces are liable to become more pervasive in our society (e.g., through mobile phones). While these signals offer new and exciting mechanisms for the control of interactive systems, the issue of whether these physiological interfaces are ap- propriate for application and offer the user a meaning- ful level of interaction remains relatively unexplored. This workshop sets out to bring together researchers working in the field of psychophysiological interaction to discuss the issue of how to design physiological interac- tions that are meaningful for users. Keywords Physiological computing, BCI, biocybernetic adaption, ambulatory monitoring, meaningful interaction ACM Classification Keywords H.5.2 User Interfaces: Input devices and strategies B.4.2 Input/Output Devices: Channels and controllers. Copyright is held by the author/owner(s). CHI 2011, May 7���12, 2011, Vancouver, BC, Canada. ACM 978-1-4503-0268-5/11/05. Stephen H. Fairclough Liverpool John Moores University Liverpool, UK s.fairclough@ljmu.ac.uk Kiel Gilleade Liverpool John Moores University Liverpool, UK gilleade@gmail.com Lennart E. Nacke University of Saskatchewan Saskatchewan, Canada lennart.nacke@acm.org Regan L. Mandryk University of Saskatchewan Saskatchewan, Canada regan@cs.usask.ca CHI 2011 ��� Workshop May 7���12, 2011 ��� Vancouver, BC, Canada 65

General Terms Design, Experimentation, Legal Aspects Introduction Physiological interfaces are currently undergoing a boom in popularity as sensor technology is becoming cheaper and more convenient to use (i.e., wearable). Therefore, brain and body interactive systems are being experimented with in a wide range of different applica- tion domains, from health and fitness to entertainment and self-experimentation [4,6]. Physiological interac- tion has traditionally been used as medical tool, for example as an alternative form of input control for dis- abled persons or a form of psychological state man- agement (i.e., biofeedback therapies). Of late physio- logical interfaces have focused on exploring what ben- efits these types of interactions offer healthy people. For example: in task performance [1] and enter- tainment [2,6]. Physiological interactive systems (or computers) are still in their explorative phase, as prior limitations in sensing technologies have limited the de- ployment of physiological computers to controlled envi- ronments [5]. However, since sensors become less of an issue, it is easier to explore what type of user ex- periences can be facilitated with physiological signals. Categories of Physiological Computers There is a broad range of different types of physiologi- cal computing systems. In Figure 1, an attempt to cap- ture the different categories of how we understand physiological computing systems has been made. The first category refers to conventional input devices, for example, a mouse and keyboard, and body tracking. The second category refers to muscle interfaces such as cursor control via gaze movement in eye tracking sys- tems. Most of these interfaces use electromyography (EMG) to capture the electrical activity in a specific muscle, which is then translated into a system com- mand. Figure 1. Categories of Physiological Computer Systems The third category refers to brain-computer interfaces (BCI) where brain activity is used to drive a computer system. These three categories of system refer to overt and intentional control at the computer interface. The other two categories adopt a ���wiretapping��� approach where physiology is monitored covertly in the absence of intentional control on the part of the user, some- times for evaluating user experience facets such as emotion. The fourth category, biocybernetic adaptation, refers to those systems that passively monitor psycho- physiological changes in the user related to cognition, emotion and motivation to inform real-time software adaptations. The final category, ambulatory monitoring, refers to the continuous collection of physiological data via wearable sensors. Physiological data is inherently multidimensional, reflecting physical activity and health as well as psychological variables. Ambulatory monitor- ing based systems incorporate telemedicine applica- tions and software designed for self-tracking and per- CHI 2011 ��� Workshop May 7���12, 2011 ��� Vancouver, BC, Canada 66