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텐서 이미지 및 고급 심층 신경망을 이용한 성 학대 이후 외 상후 스트레스 발달 과정에서의 뇌 백질 이상성 분석
No full text학위논문(석사) -- 서울대학교대학원 : 자연과학대학 뇌인지과학과, 2024. 2. Jiook Cha.Objective: Experiencing sexual assault can significantly increase the likelihood of developing posttraumatic stress disorder (PTSD). Therefore, this study sought to investigate the relationship between sexual assault and the psychological trauma load, as well as alterations in the white matter intensity among sexual assault survivors, with a particularly focuse on two distinct timeframes: initially at one month and subsequently after undergoing treatment, at six months post-assault. In addition to statistical-based neuroimaging techniques, this study leveraged deep learning transfer techniques informed by big data, alongside explainable artificial intelligence, to decode the intricate patterns of brain alterations in sexually abused adolescent girls.
Methods: In the initial phase of our study, we explored the complex relationship between childhood trauma load, brain white matter features, and the onset of post-traumatic disorder (PTSD) symptoms in sexual assault survivors using regression analysis. Afterward, our focus shifted towards scrutinizing the mediating role of white matter integrity in the progression of PTSD symptoms, particularly investigating how alterations in white matter might serve as a neurological pathway translating sexual abuse trauma into PTSD symptomatology. In this study, we conducted a detailed examination across two different timeframes: one and six months following the sexual assault. To address the challenges presented by the small sample size and the previous variability in neuroimaging techniques, we employed a deep neural network approach. Specifically, we utilized a pre-trained model developed with the Adolescent Brain Cognitive Development (ABCD) repository, similar to this Brazilian PTSD study, transferring weights to a smaller dataset from sexual abuse survivors.
Result: Upon exploring the neural ramifications of childhood sexual abuse and its trajectory on PTSD, our study revealed that the childhood trauma questionnaire (CTQ) sexual abuse scores significantly influenced fractional anistropy (FA) in the Corticospinal Tract, independent of age and sex considerations. At the 1-month follow-up, only the direct effects of sexual abuse on the brain were evident without extending to PTSD symptoms. However, only the Corticospinal Tract have the indirect effect on the 6-month PTSD symptom score, as evidenced by an average causal mediation effect (ACME) of 0.4198 (P-value < 0.05, FDR corrected) and an average direct effect (ADE) of -0.6465 (P-value < 0.05, FDR corrected). Furthermore, in the 6-month longitudinal assessment post-treatment, emotional abuse was found to affect the Cingulum area, with an ACME of 0.0855 (P-value <0.05, FDR corrected) and an ADE of 0.6294 (P= 0.054, FDR corrected). Moreover, large ABCD study cohort, we adapted this model to a smaller, distinct dataset comprising 38 Brazilian adolescent girls who experienced sexual assault. Utilizing transfer learning, our model significantly outperformed, achieving 100% Area Under the Curve (AUC), a substantial improvement over the 57.89% AUC of baseline models. This underscores the models enhanced precision in individual neuroimaging analysis, particularly in data-limited contexts. Finally, explainable artificial intelligence techniques pinpointed the corticospinal tract as vital in the models learning process, showcasing the models capability to discern complex neuroimaging patterns.
Conclusion: This study elucidated the impact of childhood trauma symptoms after sexual assault event on brain structure and function. By concentrating on children who have endured sexual abuse, a subset of trauma with distinct characteristics, our analyses have investigated the specificity of such experiences on white matter alterations. Therefore, this study revealed neuropathological changes associated with sexual abuse in adolescents.목적: 자연재해, 감정적인 학대 등 여러 트라우마를 경험한 피해자들은 대부분 PTSD 증상이 발현될 확률이 높다. 그 중에서도 성학대를 당한 아이들은 PTSD 발현될 확률이 높을 뿐만 아니라 장기적으로 뇌백질에 영향을 주게 될 가능성이 높다고 알려져 있다. 본 연구는 성학대를 경험한 브라질 청소년 여자아이들에 대하여 1개월 , 6개월 다른 시간적 조건에 따라 성학대의 경험이 뇌에 어떻게 영향을 미치는지 알아보고자 하였다. 더불어, 통계분석을 넘어 빅데이터로 학습된 딥러닝 전이학습과 설명가능한 인공지능을 활용하여 성학대를 당한 아이들의 뇌의 복잡한 패턴을 알아보고자 하였다.
방법: 본 연구의 첫번째 단계에서는 성 강간을 당한 후 아이들의 성학대, 감정학대, 신체적 학대를 포괄한 트라우마 점수가 각각 뇌에 어떻게 영향을 미치고 PTSD 증상 점수에 어떻게 영향을 미치는지 알아보았다. 더불어, 어린시절 트라우마가 뇌를 매개로하여 각각 다른 시점에서 PTSD 증상에 영향을 주었을 것이다라는 가설을 바탕으로 매개분석을 진행했다. 추가적으로, 기존 univariate 통계분석을 바탕으로한 뉴로이미징 분석기법을 극복하고, 작은 샘플 수에도 복잡한 뇌 패턴을 분류, 분석하고자 Adolescent Brain and Cognitive Development (ABCD) 를 이용한 빅데이터를 활용해 성학대에 특정된 백질 뇌이미징에 특화된 딥러닝 모델을 만들어 브라질의 성학대를 당한 아이들에 대하여 전이학습을 진행하여 복잡한 뇌 구조를 정확하게 읽고자 하였다.
결과: 1 개월 시점에서 오직 corticospinal tract 영역이 뇌백질에 가장 큰 영향을 미쳤으나, 1 개월 시점 PTSD 증상에 영향을 주지 않았고, 6 개월 시점의 PTSD 증상에 뇌를 통한 매개효과를 가졌다 (Average Causal Mediation Effect : 0.4198 (P-value < 0.05, FDR corrected , Average Direct Effect = - 0.6465 (P-value <0.05, FDR corrected)) 그러나 6 개월 시점에서는 감정적 학대만이 Cingulum 영역을 통한 6 개월 시점 PTSD 증상에 매개효과를 가졌다 (Average Causal Mediation Effect : 0.085 (P-value < 0.05, FDR corrected), Average Direct Effect = 0.6294 (P-value = 0.056 ,FDR corrected)). 다음으로 Adolescent Brain and Cognitive Development (ABCD) 대규모 데이터셋을 활용해 성학대에 특정된 백질 영역에 대한 MRI 을 훈련한 후 얻어낸 모델을 통하여 성학대를 당한 아이들에 대하여 전이 학습을 실시하였다. 그 결과 기존 작은 데이터 셋을 deep neural network 로 활용한 학습 성능이 57.98% 였던 것에 반해 전이학습에 의한 performance 는 100% 인 결과를 얻을 수 있었다. 더불어, 설명가능한 인공지능 기법을 통해 통계분석 기법과 같은 결과인 corticospinal tract 영역과 cingulum 영역이 딥러닝 학습과정에서 중요하게 사용되었다는 것을 확인할 수 있었다.
결론: 본 연구는 아이들의 트라우마가 뇌에 어떠한 영향을 주어 어떻게 영향을 미치는지 알아보고자 하였다. 그 중에서도 트라우마 중에서도 다른 특성을 갖는 성강간을 당한 아이들에 대하여 특이성에 대하여 여러가지 분석을 진행해서 뇌 백질이 어떻게 변하는지 알아보았다. 이를 통해 성학대를 당한 아이들에게 특정된 뇌 이상성을 밝혔다.II. Table of Contents
Abstract I
Table of Contents II
Acknowledgement III
Purpose of Research and Thesis Outline IV
Background V
Chapter 1
Unveiling Neurobiological Pathways: Interplay between childhood trauma and
white matter changes in sexual assault survivors
1.1 Introduction 1
1.1.1 Sexual abuse trauma impact on childhood development 1
1.1.2 Infleunce of sexual abuse on PTSD development 2
1.1.3 Trauma impact on brain microstructure 3
1.2 Method 4
1.2.1 Childhood trauma score (CTQ) 4
1.2.2 PTSD symptom score (CAPS) 5
1.2.3 Flowchart of individuals experience over timespan of the study 7
1.2.4 Tract-Based Spatial Statistics (TBSS) Analysis 7
1.2.5 Demographics 9
1.2.6 Statistical analysis 11
1.3 Result 14
1.3.1 TBSS analysis of white matter integrity discrepancies 14
1.3.2 Result of statistical analysis 17
1.3.3 Result of the links between childhood trauma, white matter integrity
and PTSD symptoms 21
1.3.4 Correlation analysis results 25
1.4 Discussion 27
Chapter 2
Advancing neuroscience through artificial intelligence applications: Coupling deep
learning and diffusion tensor imaging (DTI) to characterize the repercussions of
traumatic events
2.1 Introduction 31
2.1.1 Motivation 31
2.1.2 Deep neural network for medical imaging 33
2.1.3 Utilizing CNN for diagnostic analysis in 3D MRI 34
2.1.4 Multimodal Learning in 3DCNN 36
2.1.5 Application of XAI in deciphering deep learning predictions 37
2.2 Methods 38
2.2.1 Diffusion MRI preprocessing 38
2.2.2 Proposed method 39
2.2.2.1 3DCNN backbone model 40
2.2.2.2 Multimodal feature extraction 40
2.2.2.3 Fusion and training methology 41
2.2.2.4 Implementation details and model training 41
2.2.3 Cross-Modal attention mechanism 41
2.2.4 Training losses 43
2.2.5 Supervised Learning for Pre-training 45
2.2.5.1 Data acquisition 45
2.3 Results 45
2.3.1 Supervised Learning for each abuse type using the ABCD dataset 45
2.3.1.1 Evaluating the performance in the classification of trauma 46
2.4 Transfer Learning 48
2.4.1 Model interpretation using XAI 53
2.5 Ablation Studies 56
2.5.1 Comparative analysis: Single versus Multi-Modal 56
2.5.2 Impact of attention mechanism on multimodal CNN performance
58
2.5.3 Comparision to the other models 59
2.6 Discussion 60
Chapter 3. General discussion and conclusion 63
3.1 Discussion and conclusion 63
3.2 Limitation 65
Supplementary 67
Bibliography 73
Abstract in Korean 81석
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koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
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Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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