Abstract
The rapid development of social network services (SNSs) has created new challenges and opportunities for online discussion activities. Because synchronous and asynchronous discussions have pros and cons, the present research team developed seamless online learning integrated discussion (SOLID), which integrates synchronous and asynchronous discussions within the online discussion environment. In this environment, students' cognitive processing patterns and changes in patterns throughout the discussion contributed to our understanding of their strengths and limitations. Thus, we adopted project-based discussion activities as teaching activities, and we explored students' cognitive processing in an integrated discussion environment through lag and progressive sequential analysis. The results revealed that this environment elevated the diversity of student cognitive process throughout the online discussion. Moreover, the complete set of cognitive processing patterns could be divided into four periods, including the initial period, growth period, regulated period, and stable period. This study also discussed the features and limitations of cognitive processing in each period.