This investigation examined processing load during aspects of sentence comp
rehension in non-brain-damaged subjects. Our goals were to begin the proces
s of quantifying the loads associated with on-line and off-line aspects of
sentence processing and to evaluate the utility of visuomotor tracking as a
n index of the resource demand associated with elements of sentence compreh
ension. Subjects were required to track an unpredictable visual target with
their forefinger while listening to sentences and answering Yes-No compreh
ension questions. In general, tracking performance declined during the off-
line task of responding to questions compared to the on-line task of listen
ing to sentences and questions. Performance was also poorer during the begi
nning and end of the sentence compared to the middle of the sentence. Resul
ts are discussed in relation to resource theories of normal and aphasic sen
tence comprehension.