The updating process is crucial to the development of a situation model. Th
e process may be either an online or a delayed process. These 2 opposite as
sumptions led us to investigate the time course and quality of the updating
process. We assumed that the updating process is sensitive to readers' pri
or knowledge and to the task that participants have to perform. We compared
the data obtained with 2 tasks that both assessed the integration of the s
ame information: a probe task inserted during the comprehension of the text
and an inference judgment task presented after the text comprehension. Our
results demonstrated that all readers can update their situation model onl
ine, but the delayed integration of new incoming information requires a hig
h level of prior knowledge of the situation described. Moreover, the online
updating is enhanced when participants complete a task that strengthens th
e model that initially is built. The implications for this new view of the
updating process are discussed within current theories of text comprehensio
n.