Sleep quality in PTSD-diagnosed women in South Africa: cognitive-affective associations In Brief: Why is sleep important? Gosia Lipinska Sleep and neutral declarative memory consolidation Diekelmann & Born, 2010 In Brief: Why is sleep important? Sleep and emotional memory consolidation Positive + negative > neutral Healthy sleep = balanced consolidation Sleep deprivation = negative > positive or neutral Role of REM sleep 1
In Brief: Why is sleep important? In Brief: Memory and Emotion Processing in PTSD Sleep and emotional reactivity Autonomic arousal REM sleep attenuates emotional reactivity Neutral declarative memory Poor free recall in comparison to TE and HC No difference in retention Hippocampus?? Emotion memory and reactivity Biased memory for negative stimuli Elevated emotional reactivity in response to negative and arousing stimuli Walker, 2009 In Brief: In Brief: Why study sleep in PTSD Characteristics of sleep in PTSD Diagnostic criteria: insomnia and nightmares Subjective reports of very poor sleep Less SWS More stage 1 NREM REM sleep abnormalities REM density REM fragmentation in the aftermath of a trauma predicts the development of PTSD PTSD sleep disturbances PTSD memory and emotional disturbances Perhaps not an accident 2
In Brief: Why is study sleep in PTSD? Methods Participants PTSD Prevalence in South Africa is 2.3% and conditional prevalence is 3.5% Experiencing trauma places demands on public health system In LMIC there are few resources A place for sleep therapies? Participants: women 18-40 years old PTSD TE* n= 21 n= 19 Trauma < 6 months Trauma > 5 years HC** n= 20 Walker, 2009 *TE = Trauma-Exposed non-ptsd; **HC = healthy control Methods Materials Subjective sleep report PSQI Nihon Khoden polysomnograph (PSG) Noradrenergic activity Urine metabolites 3
Methods Materials Methods Procedure Logical Memory; Word List; Story Memory Methods Materials VrijeUniversiteitAmbulatory Monitoring System (VU-AMS) International Affective Picture System (IAPS) 4
Subjective reports ** ** * * p<.05,** p<.01 Objective GL1 polysomnograph No between-group differences in gross architecture Sleep stage differences REM arousals PTSD > TE and HC, n.s. 100 90 80 70 60 50 40 30 20 10 0 PTSD TE HC REM% SWS% NREM2% NREM1% TE = trauma-exposed; HC = healthy control Neutral Declarative Memory and PTSD < healthy controls delayed recall and retention after sleep immediateand delayed recall but not retention across waking. N.s. between TE participants and participants in the other groups 5
Slide 18 GL1 bring in findings from other studies Gosia Lipinska, 2018/03/25
Neutral Declarative Memory and Across Sleep * * * * Across Waking PTSD Trauma-Exposed Healthy Control Neutral Declarative Memory and Emotional Memory and Predicting Night-time Neutral Declarative Retention Emotion Memory : all participants i.e. balanced accuracy Note. For the overall model, R 2 =.41, adjusted R 2 =.35. Retention REM fragmentation PTSD: r= -.50, p =.03; TE: r= -.13, p =.60; HC: r=.17, p =.47 : all participants > i.e. biased accuracy 6
Emotional Memory and Recognition accuracy: Comparing picture type after sleep and waking Emotional Reactivity and Emotion Reactivity Mean Recognition Accuracy 3 2.5 2 1.5 1 0.5 0 High Arousing Negative High Arousing Positive Low Arousing Neutral High Arousing Negative High Arousing Valence and Arousal Positive Low Arousing Neutral Condition Sleep Sleep Waking : all participants, all pictures i.e. sleep attenuated emotion reactivity : all participants, all pictures i.e. waking increased emotion reactivity No relationship: REM and (i) emotion memory & (ii) emotion reactivity Emotional Memory and PEP Pre-Ejection Period and Left Ventricular Ejection Time Change: Comparing emotion reactivity to the initial presentation of a picture (pre-delay) to the repeat presentation of that picture (post-delay), within each of the Sleep and Waking conditions Sleep Waking LVET Sleep Waking pre-delay post-delay 7
Discussion : PTSD retention : PTSD retention other groups Pattern of memory performance Hippocampal functioning Saturated networks? REM fragmentation, not SWS Discussion Discussion Some evidence of objective sleep disturbance in PTSD Fairly minimal, subjective reports suggest improved sleep quality in PTSD in the lab Sleep regulates emotion memory & reactivity Not in predicted direction for emotion memory Context specific? General effect of sleep on emotional reactivity 8
Discussion Thanks! Neutral declarative memory vs. emotional memory and reactivity Totally different results Possible sensitivity of the hippocampus National Research Foundation A.W. Mellon Foundation A/Professor Kevin Thomas UCT Sleep Sciences Team vs Conclusion Good quality sleep is important for memory and emotional reactivity Sleep research in the context of psychiatric disorders helps us understand that symptoms are related 9