Although Night Vision Goggles (NVGs) support and enhance visual perception in low-light or dark conditions the optical and electro-optical characteristics of NVGs impact visual perception differently than normal light conditions. Consequently, most published studies investigating the impact of NVG use on human performance have been based on psychophysical and perception research approaches [e.g., Macuda et al. (Proceedings of the Society of Photo-optical Instrumentation Engineers (SPIE) 5442:36-44, 2004); Niall et al. (Human Factors 41(3):495-506, 1999)]. However, anecdotal reports have suggested that NVGs affect spatial orientation and way-finding, implying that NVG use also influences human cognitive functions. Few studies have systematically characterized the cognitive nature of using NVGs, particularly on spatial behavior. This paper aims to present an empirical methodology to study NVG use on way-finding and orientation performance, by introducing a spatial cognition research paradigm. The paradigm is a between subjects design composed of two main phases (1) a learning and practice phase; and (2) tests of acquired spatial knowledge. In the learning and practice phase, participants learn the environment through active navigation and way-finding, searching for targets within a life-sized maze with or without NVGs. In the second phase, knowledge of the environment is tested with two spatial memory tests (a judgment of relative direction and map drawing task). It is proposed that such an approach can be used to study both the perceptual and cognitive aspects of using head mounted vision enhancing devices, particularly for search and way-finding tasks. Furthermore, this approach can be utilized in the comparative and acceptance testing of new vision enhancing technologies. The methodology used in this study can also be utilized in developing and assessing training guidelines and strategies that are more compatible with humans' spatial cognition processes. Some practical implications regarding NVG training and possible field research to explore improvements in the design and deployment of vision-enhancing devices are also discussed. In the current study, findings show that participants using NVGs while navigating and way-finding had longer navigation times and more excess turns compared to those not using NVGs. Moreover, a significant decrease in navigation times and navigational steps compared to controls. In the judgement of relative direction task, relative direction pointing to searched objects across rooms and to distractors in the same room was more accurate for those who performed the search without NVGs. In the map drawing task, participants using NVGs were more likely to position more objects incorrectly and receive worst map goodness scores. The results demonstrate that NVGs affect spatial navigation and way-finding performance and the acquisition of spatial knowledge. By objectively characterizing the impact of NVGs on spatial way-finding and orientation, the current results provide empirical evidence beyond that of anecdotal reports. The findings empirically demonstrate the effectiveness of the research paradigm.
Department of Psychology

Gauthier, M. (Michelle), & Parush, A. (2010). A spatial cognition paradigm to assess the impact of Night Vision Goggles on way-finding performance. In Vision and Displays for Military and Security Applications: The Advanced Deployable Day/Night Simulation Project (pp. 111–122). doi:10.1007/978-1-4419-1723-2_9