The picture frames reflect the person represented in the photograph that they surround. The frame illustrates the current activity of this person and his/her activity of the past.
Source: Mynatt, E. D., Rowan, J., Craighill, S., and Jacobs, A. 2001. Digital family portraits. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’01). ACM Press, 333–340.
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