Callosal efficiency is related to sustained attention

The purpose of this study was to determine whether there is a relationship between the efficiency of interhemispheric communication (IHC) and the ability to sustain attention. Children were tested on a vigilance task in which the amount of time between target presentations (interstimulus intervals; ISI) was varied. IHC was assessed by comparing within-field and between-field matches on a tachistoscopic task. Subjects who showed better IHC had faster RTs on the long ISI trials of the vigilance task, suggesting callosal involvement in the ability to sustain attention over a long period of time in the absence of sensory input.