The role of temporal context in norm-based encoding of faces.

Research shows that the human brain encodes faces in terms of how they relate to a prototypical face, a phenomenon referred to as norm-based encoding. The goal of this study was to examine the effect of short-term exposure on the development of the norm, independently of global, long-term exposure. We achieved this by varying the sequence of presentation of the stimuli while keeping global exposure constant. We found that a systematic manipulation of the average face in a set of 10 preceding trials can shift this norm toward that average. However, there was no effect of order or recency among these trials; thus, there was no evidence that the last faces mattered more than the first. This suggests that the position of the face norm is modified by information that is integrated across multiple recent faces.