Sleep differentially impacts involuntary intrusions and voluntary recognitions of lab-analogue traumatic memories

Despite the critical role of sleep in memory and emotion processing, large remains unknown regarding how sleep influences trauma-related symptoms arising from maladaptive memory/emotional processes, such as those among patients with post-traumatic stress disorder. Employing a trauma film paradigm, we investigated how post-trauma sleep versus sleep deprivation influenced involuntary intrusions and voluntary recognition of traumatic memories. Sixty participants were randomly assigned to sleep or total sleep deprivation group following experimental trauma induction. Participants were assessed with: (a) lab-based and 7-day diary-based involuntary intrusions; (b) voluntary recognitions of traumatic memories 12-hr and 7-day post-trauma induction; and (c) post-traumatic stress disorder-like symptoms measured by the Impact of Event Scale-Revised. We found that compared with sleep deprivation, slept participants experienced fewer traumatic intrusions across 7 days, reported lower emotional hyperarousal, and showed more accurate recognition of trauma-related stimuli. Moreover, higher subjective sleep quality was associated with fewer intrusions only in the sleep group, while a reversed pattern emerged in the sleep deprivation group. These results provide novel evidence supporting the therapeutic benefits of sleep in protecting mental well-being from trauma exposure. To the extent that sleep modulates trauma-related symptoms, sleep can be conceived as the potential target for early interventions among trauma victims.