Shared consciousness ...

... Mind bending: Why our memories are not always our own - Features - Health & Families - The Independent. (Hat tip, Dave Lull.)

... the study of sibling memories also convincingly demonstrates how two forces go head to head in memory. There is the drive to represent events accurately, which means being true to the often vivid impressions we have about what actually happened. And there is the drive for coherence, the need to produce a narrative whose elements fit together. In this case, coherence is a matter of agreement between people. Our stories need to make sense to us individually, but they also need to make sense to those who matter to us.