Theta Activity During Navigation in Virtual Environments

Human navigation has gone through many different stages, from guidance by stars to guidance by technology. Theories for performance differences range from differences between individuals, to experience with the environment. Researchers turn to virtual environments during experimentation which are easy to manipulate and easier to measure during navigation. However, fidelity is an issue with regard to transfer of learning to a real world environment. We examined differences in theta activity during navigation in low and high fidelity virtual environments. The researchers recruited thirty-two students between the ages of 18-40 from the university subject pool for voluntary participation. We measured EEG activity from three sites, Fz, Pz, Cz, way-finding strategy (Lawton's Way Finding Questionnaire), the number or trials required to learn a novel route and perceived workload on the NASA-TLX. Participants completed four mazes of differing fidelity and length. As predicted, males had higher survey scores on Lawton's Way-Finding Questionnaire and required fewer trials to reach criterion than females. Also observed were significant increases in theta activity during the high relative to the low fidelity maze. These findings support previous research demonstrating increased theta activity during navigation. Limited support was found for the hypothesis that participants would report higher subjective workload for the high relative to the low fidelity maze. NASA-TLX ratings indicated that perceived workload was highest in the high fidelity long maze relative to both short and long low fidelity mazes. No significant differences were observed for the number of trials to reach criterion as a function of either maze fidelity or length. Participants did not require any additional trials following the learning phase before being able to complete each of the routes without error. Together the current results suggest that the fidelity of a virtual environment is a significant contributor to the concurrence between perceived workload and neurological activity in real and virtual navigation tasks.