Neural correlates of spatial term use.

The current research used event-related brain potentials (ERPs) to assess the processes underlying online apprehension of the spatial term above. Constituent steps defined within G. D. Logan and D. D. Sadler's (1996) computational theory of apprehension were associated with distinct modulations of ERPs. Specifically, finding the relevant objects was associated with an amplitude modulation of P3; competition in assigning directions to space was associated with modulation of a frontal slow wave; and computing and comparing the spatial relation was associated with modulation of a parietal slow wave. These modulations were differentially influenced by the type of reference frame used to define the spatial term and by the participant's response. The current study supports this decompositional approach to apprehension and provides a means of assessing each step independently.