Final answer:
Karen is experiencing source amnesia, a memory error where she recalls information but forgets the source, causing her to integrate others' traumatic stories into her own life history.
Step-by-step explanation:
Karen's experience of mistakenly recalling details from others' traumatic stories as if they happened to her best illustrates the dangers of source amnesia. Source amnesia is a type of memory error where a person can recall certain information but forgets where or how they acquired it. In Karen's case, attending multiple group therapy sessions exposed her to several traumatic narratives that she later misattributed to her own past experiences. This confusion over the origin of memories can lead to the blending of true personal experiences with information acquired from other sources, resulting in the formation of false memories.
Source amnesia can be particularly prevalent in situations involving high emotional arousal, such as the group therapy sessions for survivors of childhood sexual abuse that Karen attended. Because personal relevance and emotions can strengthen memory encoding, the traumatic content discussed in these settings can sometimes be mistakenly integrated into one's own personal history.