  Information sharing is a ubiquitous and consequential behavior that has been
proposed to play a critical role in cultivating and maintaining a sense of
shared reality. Across three studies, we tested this theory by investigating
whether or not people are especially likely to share information that they
believe will be interpreted similarly by others in their social circles. Using
neuroimaging while members of the same community viewed brief film clips, we
found that more similar neural responding of participants was associated with a
greater likelihood to share content. We then tested this relationship using
behavioral studies and found (1) that people were particularly likely to share
content about which they believed others in their social circles would share
their viewpoints and (2) that this relationship is causal. In concert, our
findings support the idea that people are driven to share information to create
and reinforce shared understanding, which is critical to social connection.
