Insomnia is one of the most common health issues, with occasional symptoms affecting up to 50% of the general population. Lack of sleep is associated with many negative health effects. A new evolutionary hypothesis has been proposed to explain the mechanism behind insomnia symptoms. The evolutionary-emotional hypothesis proposes that while acute insomnia might be advantageous from an evolutionary perspective, chronic insomnia is maladaptive and may follow from a failure or delay of fear extinction. The aim of the current thesis was to investigate which neural mechanisms might be at work if one is to consider the evolutionaryemotional hypothesis about the causes of insomnia plausible and to review studies from cognitive neuroscience to discover what support there might be for the hypothesis. Studies have found heightened activation in fear-related brain areas in insomnia patients. Delayed fear extinction and altered emotion regulation circuitry, among other things, were also observed for insomnia patients. However, few experimental studies on the effect of fear extinction on sleep in insomnia patients have been conducted. At this time, some emerging evidence lends support for the evolutionary-emotional hypothesis of insomnia, but more studies that directly assess fear conditioning and fear extinction processes in insomnia patients are needed to assess the explanatory power of the theory.

研究目的：再評估策略在清醒時是廣為使用且能夠有效降低負向情緒的方法之一。若個人在睡前使用，應預期也能降低情緒而促進入睡。然而，調查研究卻發現睡前使用再評估策略的習慣與入睡歷程未有預期的正向關連。研究者回顧發現，再評估策略可能包含了各種不同性質的次分類，高控制性的再評估策略可能會導致過度激發狀態，影響入睡。本研究目的即在於比較控制性高（改變對當下情境的詮釋）與低（接受）的再評估策略，讓兩組受試者在使用不同策略後嘗試入睡，並詢問其入睡歷程下的主觀入睡經驗。預期高控制再評估策略會導致受試者較高的認知激發狀態，而在階段二睡眠喚醒後有較多人自陳仍有思考活動，較少人自認已經睡著，以釐清入睡前使用不同次分類再評估策略所造成的控制性認知活動，可能對入睡歷程帶來的影響。 研究方法：本研究共招募26名受試者，並隨機分派至接受組（13人，7位男性，6位女性，平均年齡23.6歲）與對當下情境詮釋組（13人，男性6位，女性7位，平均年齡24.9歲）。受試者皆須依序經過中性情境以及情緒誘發情境兩個夜晚。在情緒誘發情境下，主試者會對其表現給予負向回饋以引發情緒，接著依不同組別要求受試者在睡前使用不同再評估策略來調適情緒，隨後嘗試入睡。同時，主試者會在睡前測量受試者的認知激發狀態，並於進入階段二睡眠後，即時喚醒詢問其入睡歷程意識經驗，包含主觀入睡知覺（自評睡著與否）、思考活動（是否仍有思考）等。 研究結果：本研究結果顯示，睡前使用高控制性策略，的確造成較高的入睡前控制活動，形成較高認知激發狀態，影響入睡歷程。在階段二睡眠喚醒後，使用較高控制性策略的組別也較另一組有較高比例報告仍在思考，覺得自己尚未睡著，並低估自己有睡著的時間。 結論：本研究探討控制性不同的再評估策略對主客觀入睡歷程的影響。研究結果支持高控制性策略會造成認知激發狀態，並使受試者在客觀定義入睡喚醒後，仍有較多的思考活動與較少的入睡知覺，同時較低估自己有睡著的時間，顯示入睡前較高的控制性認知活動，的確可能影響受試者的入睡歷程。這支持了先前研究對再評估策略並非單一構念的假設，未來研究再評估策略時，須考慮其次分類才能有全面性的了解。最後，對照過去研究，睡前使用再評估策略的習慣與入睡歷程未有預期的正向關連，可能是與未考慮控制性有關。 / Objective: Reappraisal was found to be effective to decrease negative emotion, thus is considered to be an useful strategy for emotion regulation, because it was (Gross, 1998; 2001). Since negative emotion is associated with sleep disruption, reappraisal is supposed to facilitate sleep-onset. Nevertheless, previous study did not support this point of view (Harvey, 2001; Ree et al., 2005). There was a negative association reported between use of reappraisal and sleep quality in insomnia patients. Researchers have identified different types of reappraisal strategies (McRae et al., 2011) with different levels of controlling cognitive activity. The unexpected association between reappraisal and sleep might be due to the impact of increased level of cognitive activity associated with reappraisal. This study aims to compare the effects of two types of reappraisal strategies, change thought (high cognitive activity) and accept feelings (low cognitive activity), on sleep onset process. Methods: Twenty six participants were recruited for this study, randomized to one of two groups (Acceptance group: N=13, average age=23.6 years; Change group: N=13, average age=24.9 years). Each participant will go through two nights of sleep recording at the sleep lab. The first night was baseline condition; the second night was experimental condition. After the emotion induction, the experimenter instructed the participants to use different reappraisal strategies to regulate their emotion, and then asked them to try to fall sleep in the experimental night. The experimenter woke up participants after 5-min after the start of stage 2 sleep, and asked their subjective experience right before waking up, including sleep perception (sleep or not) and thinking experience. Results: As expected, the Change group had higher controlling cognitive activity and arousal level than the Acceptance group before going to bed. Then, after waking up participants on stable stage 2 sleep, the Change group had higher thinking experience, lower sleep perception and underestimated sleep time than Acceptance group. Conclusions: The findings of this research show that high controlling activity reappraisal could have a negative impact on sleep-onset period than low controlling activity reappraisal. The result supports our hypothesis that controlling cognitive activity can increase pre-sleep arousal level that further increase cognitive activity during sleep-onset period and decrease the perception of sleep.

Les troubles anxieux sont parmi les troubles psychiatriques les plus souvent diagnostiqués chez les adolescents. Ces troubles sont souvent accompagnés de nombreuses comorbidités, dont des difficultés de sommeil. L’objectif principal de cette thèse est de caractériser l’activité corticale à l’éveil et pendant le sommeil à l’aide de l’EEG quantifié chez une population d’adolescents présentant un trouble anxieux, et de la comparer à un groupe témoin d’adolescents. Dans un second temps, on cherche à savoir si l’activité EEG des patients anxieux corrèle avec différentes mesures cliniques. Deux études permettent de répondre à ces objectifs, une première portant sur l’activité EEG au cours de l’éveil, et une seconde portant sur l’activité EEG au cours du sommeil (SL et SP). La première étude démontre que l’activité EEG des deux groupes ne présente pas de différence à l’EEG le soir. Par contre, le matin, les patients anxieux présentent une activité significativement supérieure à celle des contrôles aux électrodes centrales (0,75-10 Hz et 13-20 Hz) ainsi qu’aux électrodes occipitales (2,5-7,75 Hz). Dans la seconde étude, nous avons analysé l’activité EEG absolue et relative en SL et en SP. Nous avons trouvé une activité absolue significativement supérieure à l’EEG de la région centrale chez les participants du groupe anxieux : en SLP (stades 3 et 4) sur l’ensemble des bandes de fréquence, en stade 2 sur les bandes de fréquence thêta, alpha et beta seulement. Finalement, en SP, les différences sont trouvées en alpha et beta, et non en thêta et delta. Les résultats obtenus à ces deux études suggèrent la présence de mécanismes de synchronisation et de filtrage inadéquats au niveau de la boucle thalamo-corticale, entraînant une hypervigilance du SNC. Quant aux corrélations entre l’activité EEG et les mesures cliniques, les résultats obtenus dans les deux études révèlent que les fréquences lentes (thêta et delta) de l’activité d’éveil le matin corrèlent à la fois avec l’anxiété de trait et d’état et les fréquences rapides (Alpha et Beta) de l’EEG du sommeil corrèlent sélectivement avec l’anxiété d’état. Il semble donc exister un lien entre les mesures cliniques et l’activité EEG. Une hausse d’activité EEG pourrait être un indicateur de la sévérité accrue des symptômes anxieux. / Anxiety disorders are among the most diagnosed psychiatric disorders in the adolescent population. These disorders are often accompanied by different comorbidities, such as sleep problems. The main objective of this thesis is to characterize the cortical activity during wake and sleep, using quantified EEG, in a population of adolescents presenting an anxiety disorder, and to compare these results to those of a control group of adolescents. Secondly, we wish to verify if the EEG activity of the anxious participants correlates with different clinical measures. Two different studies are conducted in order to attain our objectives, the first one being on the EEG activity during wake, and the second being on the EEG activity during sleep (slow wave sleep and rapid eye movement sleep). The first study reveals that the EEG activity from both groups does not differ in the evening. However, in the morning, anxious participants display an increased activity on central electrodes (0.75-10 Hz and 13-20 Hz), and on occipital electrodes (2.5-7.75 Hz). In the second study, we demonstrate that anxious participants show an increased absolute EEG activity on central electrodes: in slow wave sleep (stages 3 and 4), it is found on all frequency bands, in stage 2, it is found on the theta, alpha and beta frequency bands. Finally, in rapid eye movement sleep, the differences are only in alpha and beta, and not in theta and delta. These data suggest the impairment of thalamo-cortical gating mechanisms in adolescents with anxiety disorders, leading to CNS hyperarousal. As for the correlations between the EEG activity and the clinical measures, the results from our studies reveal that the slow frequencies (theta and delta) of morning wake EEG correlate with both trait and state anxiety, while fast frequencies (alpha and beta) from the sleep EEG correlate specifically with state anxiety. Thus, there appears to be an association between EEG activity and clinical measures. An increased EEG activity could be an indicator of the severity of the anxious symptoms.

Les troubles anxieux sont parmi les troubles psychiatriques les plus souvent diagnostiqués chez les adolescents. Ces troubles sont souvent accompagnés de nombreuses comorbidités, dont des difficultés de sommeil. L’objectif principal de cette thèse est de caractériser l’activité corticale à l’éveil et pendant le sommeil à l’aide de l’EEG quantifié chez une population d’adolescents présentant un trouble anxieux, et de la comparer à un groupe témoin d’adolescents. Dans un second temps, on cherche à savoir si l’activité EEG des patients anxieux corrèle avec différentes mesures cliniques. Deux études permettent de répondre à ces objectifs, une première portant sur l’activité EEG au cours de l’éveil, et une seconde portant sur l’activité EEG au cours du sommeil (SL et SP). La première étude démontre que l’activité EEG des deux groupes ne présente pas de différence à l’EEG le soir. Par contre, le matin, les patients anxieux présentent une activité significativement supérieure à celle des contrôles aux électrodes centrales (0,75-10 Hz et 13-20 Hz) ainsi qu’aux électrodes occipitales (2,5-7,75 Hz). Dans la seconde étude, nous avons analysé l’activité EEG absolue et relative en SL et en SP. Nous avons trouvé une activité absolue significativement supérieure à l’EEG de la région centrale chez les participants du groupe anxieux : en SLP (stades 3 et 4) sur l’ensemble des bandes de fréquence, en stade 2 sur les bandes de fréquence thêta, alpha et beta seulement. Finalement, en SP, les différences sont trouvées en alpha et beta, et non en thêta et delta. Les résultats obtenus à ces deux études suggèrent la présence de mécanismes de synchronisation et de filtrage inadéquats au niveau de la boucle thalamo-corticale, entraînant une hypervigilance du SNC. Quant aux corrélations entre l’activité EEG et les mesures cliniques, les résultats obtenus dans les deux études révèlent que les fréquences lentes (thêta et delta) de l’activité d’éveil le matin corrèlent à la fois avec l’anxiété de trait et d’état et les fréquences rapides (Alpha et Beta) de l’EEG du sommeil corrèlent sélectivement avec l’anxiété d’état. Il semble donc exister un lien entre les mesures cliniques et l’activité EEG. Une hausse d’activité EEG pourrait être un indicateur de la sévérité accrue des symptômes anxieux. / Anxiety disorders are among the most diagnosed psychiatric disorders in the adolescent population. These disorders are often accompanied by different comorbidities, such as sleep problems. The main objective of this thesis is to characterize the cortical activity during wake and sleep, using quantified EEG, in a population of adolescents presenting an anxiety disorder, and to compare these results to those of a control group of adolescents. Secondly, we wish to verify if the EEG activity of the anxious participants correlates with different clinical measures. Two different studies are conducted in order to attain our objectives, the first one being on the EEG activity during wake, and the second being on the EEG activity during sleep (slow wave sleep and rapid eye movement sleep). The first study reveals that the EEG activity from both groups does not differ in the evening. However, in the morning, anxious participants display an increased activity on central electrodes (0.75-10 Hz and 13-20 Hz), and on occipital electrodes (2.5-7.75 Hz). In the second study, we demonstrate that anxious participants show an increased absolute EEG activity on central electrodes: in slow wave sleep (stages 3 and 4), it is found on all frequency bands, in stage 2, it is found on the theta, alpha and beta frequency bands. Finally, in rapid eye movement sleep, the differences are only in alpha and beta, and not in theta and delta. These data suggest the impairment of thalamo-cortical gating mechanisms in adolescents with anxiety disorders, leading to CNS hyperarousal. As for the correlations between the EEG activity and the clinical measures, the results from our studies reveal that the slow frequencies (theta and delta) of morning wake EEG correlate with both trait and state anxiety, while fast frequencies (alpha and beta) from the sleep EEG correlate specifically with state anxiety. Thus, there appears to be an association between EEG activity and clinical measures. An increased EEG activity could be an indicator of the severity of the anxious symptoms.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O transtorno do estresse pós-traumático (TEPT) e alterações lipídicas são as temáticas principais dessa Dissertação. Seu objetivo principal foi investigar a associação entre o TEPT e as concentrações séricas de colesterol total (CT), lipoproteína de baixa densidade (LDL), lipoproteína de alta densidade (HDL) e triglicerídeos (TG) através de uma revisão sistemática da literatura seguida de metanálise. Adicionalmente, a relação entre essas variáveis lipídicas e os grupos de sintomas do TEPT revivescência, esquiva/entorpecimento emocional e hiperestimulação autonômica foi avaliada em um segundo estudo com dados primários. A metanálise incluiu 18 artigos, totalizando 2.110 indivíduos com TEPT e 17.550 indivíduos sem TEPT. As diferenças de médias ponderadas (DMP) mg/dL dos parâmetros lipídicos foram calculadas por modelos de efeitos aleatórios e modelos de meta-regressão foram ajustados para investigar possíveis fontes de heterogeneidade. O estudo encontrou que o TEPT foi associado a um pior perfil lipídico quando comparados a controles sem o transtorno (DMPCT= 20,57, IC 95% 12,21 28,93; DMPLDL= 12,11, IC 95% 5,89 18,32; DMPHDL= -3,73, IC 95% -5,97 -1,49; DMPTG= 35,87, IC 95% 21,12 50,61). A heterogeneidade estatística entre os resultados dos estudos foi alta para todos os parâmetros lipídicos e a variável que mais pareceu explicar essas inconsistências foi idade. O segundo artigo faz parte de um estudo maior conduzido em 2004 com 157 policiais do sexo masculino do Batalhão de Choque da Polícia Militar do Estado de Goiás (BPMCHOQUE). Somente oficiais de férias ou em dispensa inclusive dispensa médica não foram avaliados. O instrumento utilizado para o rastreio do TEPT foi a versão em português para civis da Post-Traumatic Stress Disorder Checklist (PCL-C). Trinta e nove participantes (25%) foram excluídos do estudo: dois porque falharam no preenchimento dos questionários e 37 cujas amostras de sangue não foram coletadas por vários motivos. Neste trabalho, encontrou-se uma forte correlação positiva entre as concentrações séricas de CT e LDL com o grupo de sintomas de hiperestimulação autonômica, somente no grupo TEPT: &#961;= 0,89 (p<0,01) e &#961; =0,92 (p<0,01), respectivamente. Em suma, espera-se que os resultados dessa Dissertação possam colaborar para o estabelecimento de um melhor acompanhamento clínico de pacientes com TEPT, particularmente porque estes parecem estar sob um maior risco de doenças cardiovasculares devido a um pior perfil lipídico. / Post-traumatic stress disorder (PTSD) and lipid profile changes are the main themes of this Dissertation, whose main purpose was to investigate the association between PTSD and serum lipid concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and Triglycerides (TGs). Additionally, the relationship between these serum lipid parameters and PTSD symptom clusters - re-experiencing, avoidance and hyperarousal was assessed in a second study with primary data. The meta-analysis included 18 articles, for an overall number of 2,110 people with PTSD and 17,550 individuals without PTSD. Pooled weighted mean differences (WMD) - mg/dL - of serum lipid parameters were calculated using random effects model and meta-regression models were fitted to investigate the sources of heterogeneity. The study showed that PTSD was associated with worsened lipid profile when compared to controls without PTSD (DMPCT= 20.57, IC 95% 12.21 28.93; DMPLDL= 12.11, IC 95% 5.89 18.32; DMPHDL= -3.73, IC 95% -5.97 -1.49; DMPTG= 35.87, IC 95% 21.12 50.61). Statistical heterogeneity between the results of the studies was high for all lipid parameters and the variable that most explained these inconsistencies was age. The second article is part of a larger study conducted in 2004 with 157 active duty male police officers of an elite unit of the Police Force of the State of Goiás-Brazil (BPMCHOQUE). Only officers on vacation or on leave including those on sick leave were not assessed. The diagnostic tool applied to screen for PTSD was a Portuguese version of the PTSD Checklist Civilian Version (PCL-C). Thirty nine (25%) participants were excluded: 2 respondents who failed to fill out the questionnaires and 37 whose blood samples were not collected for various reasons. The study found a significant and strong positive correlation between TC and LDL-C with hyperarousal symptom cluster, only in the full PTSD group: &#961;= 0.89 (p<.01) and &#961;= 0.92 (p<.01), respectively. As a synthesis, the results found in this Dissertation can contribute to a better clinical follow-up of PTSD patients, especially because they appear to be at higher risk for cardiovascular diseases due to worsened serum lipid profile.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O transtorno do estresse pós-traumático (TEPT) e alterações lipídicas são as temáticas principais dessa Dissertação. Seu objetivo principal foi investigar a associação entre o TEPT e as concentrações séricas de colesterol total (CT), lipoproteína de baixa densidade (LDL), lipoproteína de alta densidade (HDL) e triglicerídeos (TG) através de uma revisão sistemática da literatura seguida de metanálise. Adicionalmente, a relação entre essas variáveis lipídicas e os grupos de sintomas do TEPT revivescência, esquiva/entorpecimento emocional e hiperestimulação autonômica foi avaliada em um segundo estudo com dados primários. A metanálise incluiu 18 artigos, totalizando 2.110 indivíduos com TEPT e 17.550 indivíduos sem TEPT. As diferenças de médias ponderadas (DMP) mg/dL dos parâmetros lipídicos foram calculadas por modelos de efeitos aleatórios e modelos de meta-regressão foram ajustados para investigar possíveis fontes de heterogeneidade. O estudo encontrou que o TEPT foi associado a um pior perfil lipídico quando comparados a controles sem o transtorno (DMPCT= 20,57, IC 95% 12,21 28,93; DMPLDL= 12,11, IC 95% 5,89 18,32; DMPHDL= -3,73, IC 95% -5,97 -1,49; DMPTG= 35,87, IC 95% 21,12 50,61). A heterogeneidade estatística entre os resultados dos estudos foi alta para todos os parâmetros lipídicos e a variável que mais pareceu explicar essas inconsistências foi idade. O segundo artigo faz parte de um estudo maior conduzido em 2004 com 157 policiais do sexo masculino do Batalhão de Choque da Polícia Militar do Estado de Goiás (BPMCHOQUE). Somente oficiais de férias ou em dispensa inclusive dispensa médica não foram avaliados. O instrumento utilizado para o rastreio do TEPT foi a versão em português para civis da Post-Traumatic Stress Disorder Checklist (PCL-C). Trinta e nove participantes (25%) foram excluídos do estudo: dois porque falharam no preenchimento dos questionários e 37 cujas amostras de sangue não foram coletadas por vários motivos. Neste trabalho, encontrou-se uma forte correlação positiva entre as concentrações séricas de CT e LDL com o grupo de sintomas de hiperestimulação autonômica, somente no grupo TEPT: &#961;= 0,89 (p<0,01) e &#961; =0,92 (p<0,01), respectivamente. Em suma, espera-se que os resultados dessa Dissertação possam colaborar para o estabelecimento de um melhor acompanhamento clínico de pacientes com TEPT, particularmente porque estes parecem estar sob um maior risco de doenças cardiovasculares devido a um pior perfil lipídico. / Post-traumatic stress disorder (PTSD) and lipid profile changes are the main themes of this Dissertation, whose main purpose was to investigate the association between PTSD and serum lipid concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and Triglycerides (TGs). Additionally, the relationship between these serum lipid parameters and PTSD symptom clusters - re-experiencing, avoidance and hyperarousal was assessed in a second study with primary data. The meta-analysis included 18 articles, for an overall number of 2,110 people with PTSD and 17,550 individuals without PTSD. Pooled weighted mean differences (WMD) - mg/dL - of serum lipid parameters were calculated using random effects model and meta-regression models were fitted to investigate the sources of heterogeneity. The study showed that PTSD was associated with worsened lipid profile when compared to controls without PTSD (DMPCT= 20.57, IC 95% 12.21 28.93; DMPLDL= 12.11, IC 95% 5.89 18.32; DMPHDL= -3.73, IC 95% -5.97 -1.49; DMPTG= 35.87, IC 95% 21.12 50.61). Statistical heterogeneity between the results of the studies was high for all lipid parameters and the variable that most explained these inconsistencies was age. The second article is part of a larger study conducted in 2004 with 157 active duty male police officers of an elite unit of the Police Force of the State of Goiás-Brazil (BPMCHOQUE). Only officers on vacation or on leave including those on sick leave were not assessed. The diagnostic tool applied to screen for PTSD was a Portuguese version of the PTSD Checklist Civilian Version (PCL-C). Thirty nine (25%) participants were excluded: 2 respondents who failed to fill out the questionnaires and 37 whose blood samples were not collected for various reasons. The study found a significant and strong positive correlation between TC and LDL-C with hyperarousal symptom cluster, only in the full PTSD group: &#961;= 0.89 (p<.01) and &#961;= 0.92 (p<.01), respectively. As a synthesis, the results found in this Dissertation can contribute to a better clinical follow-up of PTSD patients, especially because they appear to be at higher risk for cardiovascular diseases due to worsened serum lipid profile.