Dynamic brain imaging: Event-related optical signal (EROS) measures of the time course and localization of cognitive-related activity

This paper describes the concept of dynamic brain imaging and introduces a new methodology, the event-related optical signal, or EROS. Dynamic brain imaging allows one to study noninvasively the time course of activity in specific brain areas. Brain imaging data can contribute to the analysis of the subcomponents of the human information processing system and of their interactions. Several brain imaging methods provide data that possess spatial and temporal resolution at various degrees and can be used for this purpose. In this paper, we focus on the EROS method, which yields data with millisecond temporal resolution and subcentimeter spatial resolution. We describe the fundamentals of this method and report several examples of the types of data that can be obtained with it. Finally, we discuss the possibility of combining different imaging methods, as well as the advantages and limitations that can be expected in this process.