Involuntary Versus Voluntary Episodic Memories: The Effects of Encoding Factors and Emotion

Contrasting views exist as to how involuntary (spontaneous) versus voluntary (intentional) episodic memories are shaped by factors at encoding. However, there is limited systematic experimental research addressing this question. The present study uses measures obtained at encoding to predict frequencies and qualities of voluntary and involuntary memories of emotional scenes. The valence and contents of the scenes affected how frequently the scenes were recalled, similarly for involuntary and voluntary recall. Intensity, negative valence, and the degree to which a scene was perceived to tell a story at encoding were the most consistent predictors of all retrieval qualities, irrespective of retrieval method. Involuntary memories had shorter retrieval times, suggesting less effort. The present findings add to the accumulating evidence that involuntary episodic memories derive from the same episodic memory system as voluntary memories and that the two ways of remembering past events are similarly influenced by emotion at encoding.