Investigating features that contribute to evaluations of intrusiveness for thoughts and memories.

What makes a thought feel intrusive? One possibility is that traumatic experiences are the primary cause of intrusive thoughts and memories. Another possibility is that experiences of intrusiveness arise from the features involved with re-experiencing. We investigated several features that may lead a thought to feel intrusive: task-congruence, repetition, and affective content. In Experiment 1, participants listened to popular song clips expected to become stuck in one's head. In Experiment 2, participants were cued to recall their own autobiographical memories. We found that both songs and autobiographical memories replaying mentally felt more intrusive when they were incongruent with the current task, cued repeatedly, and had negative emotional content. Additionally, even liked songs and positive autobiographical memories were evaluated as highly intrusive under some conditions. Based on these findings, we argue that intrusiveness is not limited to traumatic thoughts, but rather is a context-dependent evaluation influenced by a variety of features.