Students who tended to have higher cognitive engagement with the material also tended to feel that others' comments were more thoughtful and helpful rather than those who weren't. 

Student performance and cognitive engagement

Within the realm of task cohesion, cognitive engagement can be thought of as the amount of effort and/or quality of the communications and contributions toward helping one another in their work/assignments.

New York University

To have a high task cohesion is when the interactions with members of the online learning community is of high quality. This usually involves being able to integrate findings/information from previous research into their comments or interactions with someone else, therefore giving better quality feedback with more support behind their suggestions.

Task Cohesion

Altebarmakian, M., & Alterman, R. (2019). Cohesion in online environments. International Journal of Computer-Supported Collaborative Learning, 14, 443-465.

Cohesion in online environments

Cognitive Engagement in task cohesion

When measuring task cohesion, behavioral engagement involves the degree to which an individual has contributed to the online community, whether that be in comments or replies to others' comments, as well as how much they have interacted with the material individually, i.e. reading others' work or their own.

Behavioral Engagement in task cohesion

Creating a better task cohesion allows the group to share a similar identity and fosters better collaboration amongst all group members. 
Task cohesion can be increased by improving:
- social loafing
- interdependence
- collective efficacy
- collective task value
- communication quality

Improving Task Cohesion in Online Communities

Social loafing is the tendency for individuals to devote less time or effort when working with others compared to working alone.

When an individual is not engaging with others in the group to complete the goal/task at hand, there is is a lack of task cohesion and equal contribution/effort being devoted to the task. 

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