Topographic study of human event-related potentials using a task requiring mental rotation.

Event-related potentials (ERPs) were recorded during a mental rotation task that required subjects to determine whether two stimuli presented in turn had the same shape regardless of any difference in orientation. This task consisted of two conditions: the control condition, when the two stimuli presented were identical, requiring only recognition, and the experimental condition that required recognition following mental rotation. We hypothesized that differences between ERPs recorded during the control and experimental conditions were neurophysiologically correlated with mental rotation. In the experimental condition, a marked negative component arose about 430 ms after the second stimulus. The statistically significant difference between the negative components of the two conditions was maximal over the right frontocentral region, suggesting that mental rotation processing is a right hemisphere dominant function.