Brain activity and presence: a preliminary study in different immersive conditions using transcranial Doppler monitoring

Abstract

Transcranial Doppler (TCD) sonography is a brain activity measurement technique that monitors the hemodynamic characteristics of the major cerebral arteries in normal and pathological conditions. As it is not invasive, it can be easily used in combination with virtual environments (VE). In the present study, TCD has been used to analyze brain activity variations in different presence conditions during the exposure to a VE. Forty-two subjects have taken part in the experience grouped in two different visualization conditions: a CAVE-like and a single screen projection configuration. In each session, two different navigation conditions were used: a free navigation (controlled by the subject) and an automatic navigation (controlled by the system). Results show that these immersion and navigation modifications in the VE generate changes in brain activity that can be detected using TCD techniques. Several factors, one of them being presence, could be having an influence on this behavior.