Brief report| Volume 60, ISSUE 7, P788-790, October 01, 2006

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Brief Sleep After Learning Keeps Emotional Memories Alive for Years


      Sleep after learning supports memory consolidation. However, long-lasting memory effects of sleep have not yet been investigated. Postlearning sleep may be particularly involved in the long-term retention of emotional memories and could thereby contribute to the development of posttraumatic stress disorder (PTSD), a disease thought to result from overconsolidation of traumatic memories.


      Subjects (healthy men) who had learned neutral and emotional texts immediately before sleeping or remaining awake for the subsequent 3 hours were recontacted after 4 years for long-term memory assessment (forced-choice recognition test).


      Sleep following learning compared with wakefulness enhanced memory for emotional texts after 4 years (p = .001). No such enhancement was observed for neutral texts (p = .571).


      Brief periods of sleep immediately following learning cause preservation of emotional memories over several years. Sleep deprivation in the immediate aftermath of traumatic events could be a promising therapeutic measure to prevent PTSD.

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        • Born J.
        • Kern W.
        • Bieber K.
        • Fehm-Wolfsdorf G.
        • Schiebe M.
        • Fehm H.L.
        Night-time plasma cortisol secretion is associated with specific sleep stages.
        Biol Psychiatry. 1986; 21: 1415-1424
        • Cahill L.
        Sex-related influences on the neurobiology of emotionally influenced memory.
        Ann N Y Acad Sci. 2003; 985: 163-173
        • Cahill L.
        • McGaugh J.L.
        Mechanisms of emotional arousal and lasting declarative memory.
        Trends Neurosci. 1998; 21: 294-299
        • Caldwell B.A.
        • Redeker N.
        Sleep and trauma: An overview.
        Issues Ment Health Nurs. 2005; 26: 721-738
        • Charney D.S.
        • Deutch A.Y.
        • Krystal J.H.
        • Southwick S.M.
        • Davis M.
        Psychobiologic mechanisms of posttraumatic stress disorder.
        Arch Gen Psychiatry. 1993; 50: 295-305
        • Dolcos F.
        • LaBar K.S.
        • Cabeza R.
        Remembering one year later: Role of the amygdala and the medial temporal lobe memory system in retrieving emotional memories.
        Proc Natl Acad Sci U S A. 2005; 102: 2626-2631
        • Drosopoulos S.
        • Wagner U.
        • Born J.
        Sleep enhances explicit recollection in recognition memory.
        Learn Mem. 2005; 12: 44-51
        • Gais S.
        • Born J.
        Declarative memory consolidation: Mechanisms acting during human sleep.
        Learn Mem. 2004; 11: 679-685
        • Hamann S.
        Cognitive and neural mechanisms of emotional memory.
        Trends Cogn Sci. 2001; 5: 394-400
        • Hamann S.
        • Canli T.
        Individual differences in emotion processing.
        Curr Opin Neurobiol. 2004; 14: 233-238
        • Het S.
        • Ramlow G.
        • Wolf O.T.
        A meta-analytic review of the effects of acute cortisol administration on human memory.
        Psychoneuroendocrinology. 2005; 30: 771-784
        • Maquet P.
        The role of sleep in learning and memory.
        Science. 2001; 294: 1048-1052
        • Nader K.
        Memory traces unbound.
        Trends Neurosci. 2003; 26: 65-72
        • Pennartz C.M.
        • Uylings H.B.
        • Barnes C.A.
        • McNaughton B.L.
        Memory reactivation and consolidation during sleep: From cellular mechanisms to human performance.
        Prog Brain Res. 2002; 138: 143-166
        • Pitman R.K.
        Post-traumatic stress disorder, hormones, and memory.
        Biol Psychiatry. 1989; 26: 221-223
        • Plihal W.
        • Born J.
        Effects of early and late nocturnal sleep on declarative and procedural memory.
        J Cogn Neurosci. 1997; 9: 534-547
        • Plihal W.
        • Born J.
        Memory consolidation in human sleep depends on inhibition of glucocorticoid release.
        Neuroreport. 1999; 10: 2741-2747
        • Ribeiro S.
        • Nicolelis M.A.
        Reverberation, storage, and postsynaptic propagation of memories during sleep.
        Learn Mem. 2004; 11: 686-696
        • Rugg M.D.
        • Yonelinas A.P.
        Human recognition memory: A cognitive neuroscience perspective.
        Trends Cogn Sci. 2003; 7: 313-319
        • Schelling G.
        • Briegel J.
        • Roozendaal B.
        • Stoll C.
        • Rothenhausler H.B.
        • Kapfhammer H.P.
        The effect of stress doses of hydrocortisone during septic shock on posttraumatic stress disorder in survivors.
        Biol Psychiatry. 2001; 50: 978-985
        • Schelling G.
        • Kilger E.
        • Roozendaal B.
        • de Quervain D.J.
        • Briegel J.
        • Dagge A.
        • et al.
        Stress doses of hydrocortisone, traumatic memories, and symptoms of posttraumatic stress disorder in patients after cardiac surgery: A randomized study.
        Biol Psychiatry. 2004; 55: 627-633
        • Schürer-Necker E.
        Gedächtnis und Emotion: Zum Einfluss von Emotionen auf das Behalten von Texten [Memory and Emotion: On the Influence of Emotions on Text Retention]. Psychologie Verlags Union, Munich1994
        • Smith C.
        Sleep states and memory processes.
        Behav Brain Res. 1995; 69: 137-145
        • Smith C.
        Sleep states and memory processes in humans: Procedural versus declarative memory systems.
        Sleep Med Rev. 2001; 5: 491-506
        • Stickgold R.
        Sleep-dependent memory consolidation.
        Nature. 2005; 437: 1272-1278
        • Stickgold R.
        • Walker M.P.
        Memory consolidation and reconsolidation: What is the role of sleep?.
        Trends Neurosci. 2005; 28: 408-415
        • Wagner U.
        • Degirmenci M.
        • Drosopoulos S.
        • Perras B.
        • Born J.
        Effects of cortisol suppression on sleep-associated consolidation of neutral and emotional memory.
        Biol Psychiatry. 2005; 58: 885-893
        • Wagner U.
        • Gais S.
        • Born J.
        Emotional memory formation is enhanced across sleep intervals with high amounts of rapid eye movement sleep.
        Learn Mem. 2001; 8: 112-119
        • Wagner U.
        • Gais S.
        • Haider H.
        • Verleger R.
        • Born J.
        Sleep inspires insight.
        Nature. 2004; 427: 352-355
        • Walker M.P.
        • Brakefield T.
        • Hobson J.A.
        • Stickgold R.
        Dissociable stages of human memory consolidation and reconsolidation.
        Nature. 2003; 425: 616-620
        • Walker M.P.
        • Stickgold R.
        Sleep-dependent learning and memory consolidation.
        Neuron. 2004; 44: 121-133