The Neurocognitive Role of "Absence" in Multimodal Simulator Protocols

While much has been written about the importance of the experience of presence in simulation protocols, the role of "absence" deserves more close attention. The role of subjective experience and neurophysiologic processes involved in fluctuating states of consciousness is a key issue in developing assessment and treatment tools using virtual /immersive methodologies. This paper proposes that when engaging in an interactive task, there are fluctuations of consciousness that determine both motivational engagement and measured performance. Rather than expecting a continuous experience, both in terms of perceptual and motor output flow, factors such as circadian fluctuations, fatigue and actual intrusion of sleep into waking consciousness are relevant to be aware of in assessments and treatments using virtual methodologies. This is particularly relevant in treatment populations with neurological and psychiatric disorders, where such disturbances are more common. Research in this field performed by our group at University Health Network Sleep Research Unit, University of Toronto has originated from the study of processes occurring during unconscious sleep states, and evolved into connecting these to differential simulation performance measurements in conjunction with disturbances in sleep and wakefulness. A series of experiments examining these phenomena in relation to a standardized driving simulation protocol we have developed are described