What do we know about cognitive and motivational effects of small group tutorials in problem-based learning?

Students collaborating in small groups is a characteristic of problem-based learning (PBL) that is receiving increased consideration in the literature. In this paper findings from studies in this area are synthesized and discussed. A distinction is made between studies focusing on cognitive effects of group learning and studies focusing on motivational effects of group learning. Studies concentrating on the cognitive effects of small-group PBL seem to demonstrate that activation of prior knowledge, recall of information, causal reasoning or theory building, cognitive conflicts leading to conceptual change and collaborative learning construction take place in the tutorial group. Studies focusing on the motivational effects of PBL demonstrate that group discussion positively influences students' intrinsic interest in the subject matter under discussion. The studies also demonstrate that a haphazard discussion in the tutorial group or a discussion that just scratches the surface, probably caused by students being less motivated, inhibits student learning. Several studies are reported providing suggestions on how to optimize group work in PBL. Although the studies demonstrate that group learning in PBL may have positive effects, much more research is needed to obtain more evidence and deeper insight in the cognitive and emotional effects of small group learning in PBL.