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Publication Open Access A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology(Aves, 2017) Ulaşoğlu-Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut; N/A; N/A; Onay, Aslıhan; Eser, Hale Yapıcı; Faculty Member; School of Medicine; N/A; 134359PURPOSE: Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. METHODS: A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps ofVBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. RESULTS: Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). CONCLUSION: Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia.
Publication Metadata only A correlation network analysis of dissociative experiences(Routledge Journals, Taylor & Francis Ltd, 2019) Schimmenti, Adriano; N/A; Şar, Vedat; Faculty Member; School of Medicine; 8542The interrelationships between the symptom domains of dissociation, such as the loss of continuity in subjective experience, the inability to access personal information, and the distortions about the perception of self and the environment, need to be better understood. In the current study, 2274 adults from Italy completed the Dissociative Experiences Scale-II (DES-II), and their responses were examined within a correlation network analysis framework. Fifteen dissociative experiences showed the strongest associations with the other dissociative experiences included in the measure, and they were selected for further analysis. A partial correlation network was calculated to reveal the associations between such experiences, and a community detection analysis was used to explore whether they formed distinct clusters in the network. Subsequently, a Bayesian network was estimated to examine the direction of the associations among the dissociative experiences, and a directed acyclic graph (DAG) was generated to estimate a potentially causal model of their relationships. The community detection analysis revealed three clusters of experiences that were conceptualized in terms of trance, experiential disconnectedness, and segregated behaviors. Dissociative amnesia was a common denominator of all the three clusters. The analysis of the DAG further suggested that dissociation can be conceptualized as a network in which dissociative experiences are layered into groups of symptoms that interact among them. Cognizance of the configuration and interactions among the dissociative domains and their related symptoms may be critical for better understanding the internal logic behind the dissociative processes and for addressing them effectively in clinical practice.Publication Metadata only A revised and expanded version of the Turkish childhood trauma questionnaire (CTQ-33): overprotection-overcontrol as additional factor(Routledge Journals, Taylor & Francis Ltd, 2021) Türk-Kurtça, Tuğba; N/A; N/A; N/A; N/A; Şar, Vedat; Necef, Işıl; Mutluer, Tuba; Fatih, Parmis; Faculty Member; Doctor; Faculty Member; Researcher; School of Medicine; School of Medicine; School of Medicine; School of Medicine; Koç University Hospital; 8542; N/A; 305311; N/AThis study was concerned with a culture-sensitive revision of the Turkish version of the Childhood Trauma Questionnaire (CTQ-28) and expansion of the instrument through integration of a dimension assessing overprotection - overcontrol (OP-OC). Participants (n = 783) were 37 dissociative and 78 non-dissociative and non-psychotic psychiatric outpatients, and 668 non-clinical people. They completed the revised and expanded version of the CTQ, Dissociative Experiences Scale, Beck Depression Scale, and Relationship Scales Questionnaire. A test-retest assessment was conducted on 25 non-clinical individuals. Among twenty-one alternative and the twenty-five original statements, the items of subsections were selected by correlations between item and item deleted total scores for each subset of original and alternative statements. The 33-item final version (CTQ-33) included five statements for each subsection including OP-OC and three denial items. The principal component analysis on items of the CTQ-33 with a varimax rotation yielded six factors including OP-OC. The inner consistency and the test-retest reliability were good. OP-OC correlated particularly with emotional abuse and neglect, and other types of trauma. There were significant correlations between CTQ-33 and depression, dissociation, and fearful attachment scores. The CTQ-33 differentiated psychiatric from non-clinical groups. The Turkish CTQ-33 is a reliable and valid instrument. OP-OC by caregivers may be as traumatic as other types of childhood adversities. Cross-cultural research would illuminate the significance of OP-OC beyond Turkish culture. The possibility of intergenerational transmission of trauma through OP-OC by fearful parents in and after times of cultural upheaval and political oppression should be considered for future research.Publication Metadata only A study on the adaptation of the HIV/AIDS-related stigma scale into Turkish(Wiley, 2022) Bahar, Zuhal; Cal, Ayse; Cavusoglu, Figen; Deveci, Aydin; Badur, Selim; Bahar, Ismail Hakki; Beşer, Ayşe; Faculty Member; School of Nursing; 143490Purpose This study aims to test the validity and reliability of the Turkish version of the HIV/AIDS-related Stigma Scale. Design and Methods The study has a methodological design. The sample included a total of 428 participants. of the participants, 198 were HIV/AIDS patients, 230 were HIV-negative individuals. The data were analyzed using the Exploratory and Confirmatory Factor Analysis. Findings The Turkish version of the HIV/AIDS-related Stigma Scale was found to be valid and reliable for the Turkish society. Cronbach's alpha was 0.93 for the community perspectives subscale and 0.89 for the patient perspectives subscale, and all the model fit indices were acceptable. Practice Implications The level of stigmatization revealed by the scale helps gain an insight into the community and patient perspectives on HIV/AIDS.Publication Metadata only Abnormal high-energy phosphate molecule metabolism during regional brain activation in patients with bipolar disorder(Nature Publishing Group (NPG), 2015) Yuksel, C.; Du, F.; Ravichandran, C.; Goldbach, J. R.; Thida, T.; Lin, P.; Gelda, J.; O'Connor, L.; Sehovic, S.; Gruber, S.; Ongur, D.; Cohen, B. M.; Department of Psychology; Dora, Begüm; PhD Student; Department of Psychology; College of Social Sciences and Humanities; N/AConverging evidence suggests bioenergetic abnormalities in bipolar disorder (BD). In the brain, phosphocreatine (PCr) acts a reservoir of high-energy phosphate (HEP) bonds, and creatine kinases (CK) catalyze the transfer of HEP from adenosine triphosphate (ATP) to PCr and from PCr back to ATP, at times of increased need. This study examined the activity of this mechanism in BD by measuring the levels of HEP molecules during a stimulus paradigm that increased local energy demand. Twenty-three patients diagnosed with BD-I and 22 healthy controls (HC) were included. Levels of phosphorus metabolites were measured at baseline and during visual stimulation in the occipital lobe using P-31 magnetic resonance spectroscopy at 4T. Changes in metabolite levels showed different patterns between the groups. During stimulation, HC had significant reductions in PCr but not in ATP, as expected. In contrast, BD patients had significant reductions in ATP but not in PCr. In addition, PCr/ATP ratio was lower at baseline in patients, and there was a higher change in this measure during stimulation. This pattern suggests a disease-related failure to replenish ATP from PCr through CK enzyme catalysis during tissue activation. Further studies measuring the CK flux in BD are required to confirm and extend this finding.Publication Open Access Acute dissociative reaction to spontaneous delivery in a case of total denial of pregnancy: diagnostic and forensic aspects(Routledge, 2017) Aydın, N.; van der Hart, O.; Frankel, A.S.; Şar, M.; Omay, O.; N/A; Şar, Vedat; Faculty Member; School of Medicine; 8542This article presents the history of a 21-year-old female college student with total denial of pregnancy who experienced an acute dissociative reaction during the spontaneous delivery at home without medical assistance where the newborn died immediately. Psychiatric examination, self-report questionnaires, legal documents, and witness reports have been reviewed in evaluation of the case. Evidence pointed to total denial of pregnancy, that is, until delivery. The diagnoses of an acute dissociative reaction to stress (remitted) and a subsequent PTSD were established in a follow-up examination conducted 7months after the delivery. Notwithstanding the inherently dissociative nature of total denial of pregnancy, no other evidence has been found about pre-existing psychopathology. For causing the newborn's death, the patient faced charges for aggravated murder, which were later on reduced into involuntary manslaughter. Given the physical incapacity to perform voluntary acts due to the loss of control over her actions during the delivery, and the presence of an acute dissociative reaction to unexpected delivery, the legal case represents an intricate overlap between insanity and incapacitation defenses. The rather broad severity spectrum of acute dissociative conditions requires evaluation of the limits and conditions of appropriate legal defenses by mental health experts and lawyers. Denial of pregnancy as a source of potential stress has attracted little interest in psychiatric literature although solid research exists which documented that it is not infrequent. Arguments are presented to introduce this condition as a diagnostic category of female reproductive psychiatry with a more neutral label: unperceived pregnancy.Publication Open Access Adverse childhood experiences and global mental health: avenues to reduce the burden of child and adolescent mental disorders(Cambridge University Press (CUP), 2022) Ceccarelli, C.; Prina, E.; Muneghina, O.; Jordans, M.; Barker, E.; Miller, K.; Singh, R.; Sorsdhal, K.; Cuijpers, P.; Lund, C.; Barbui, C.; Purgato, M.; Department of Psychology; Acartürk, Ceren; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 39271Mental disorders are one of the largest contributors to the burden of disease globally, this holds also for children and adolescents, especially in low-and middle-income countries. The prevalence and severity of these disorders are influenced by social determinants, including exposure to adversity. When occurring early in life, these latter events are referred to as adverse childhood experiences (ACEs). In this editorial, we provide an overview of the literature on the role of ACEs as social determinants of mental health through the lenses of global mental health. While the relation between ACEs and mental health has been extensively explored, most research was centred in higher income contexts. We argue that findings from the realm of global mental health should be integrated into that of ACEs, e.g. through preventative and responsive psychosocial interventions for children, adolescents and their caregivers. The field of global mental health should also undertake active efforts to better address ACEs in its initiatives, all with the goal of reducing the burden of mental disorders among children and adolescents globally.Publication Open Access Adverse childhood experiences and global mental health: avenues to reduce the burden of child and adolescent mental disorders- Corrigendum (vol 31, E75, 2022)(Cambridge University Press (CUP), 2022) Ceccar, C.; Prina, E.; Muneghina, O.; Jordans, M.; Barker, E.; Miller, K.; Singh, R.; Sorsdhal, K.; Cuijpers, P.; Lund, C.; Barbui, C.; Purgato, M.; Department of Psychology; Acartürk, Ceren; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 39271Publication Metadata only An examination of the mediating role of maladaptive emotion regulation strategies in the complex relationship between interpersonal needs and suicidal behavior(Frontiers Media Sa, 2024) Bakhshesh-Boroujeni, Michael; Farajpour-Niri, Sepideh; Hekmati, Issa; Asgarabad, Mojtaba Habibi; Department of Psychology; Eskin, Mehmet; Department of Psychology; Graduate School of Social Sciences and Humanities; College of Social Sciences and HumanitiesBackground: Studies have shown that psychological factors, notably interpersonal needs and emotion regulation, play a significant role in suicidal behavior. Interpersonal needs are significant contextual components that affect emotion regulation and contribute to a wide range of dysfunctional behaviors, such as suicidal behavior. It has been postulated that emotion regulation mediates the associations between proximal and distal risk factors of suicidal behavior. Method: The sample consisted of 340 community-dwelling individuals (62.5% women;SD = 0.48) with an age range of 18 through 55 (M = 30.23;SD = 8.54) who completed the interpersonal needs questionnaire, the suicide behaviors questionnaire-revised, and the cognitive emotion regulation questionnaire. The Structural Equation Modeling (SEM) approach was utilized to evaluate a mediation model. Results: The findings indicate that interpersonal needs (i.e., perceived burdensomeness r = .55, p <.01 and thwarted belongingness r = .25, p <.01) and putatively maladaptive cognitive emotion regulation strategies (i.e., self-blame;r = .38, p <.01, catastrophizing;r = .55, p <.01, rumination;r = .40, p <.01, and other blame;r = .44, p <.01) have strong associations with suicidal behavior, and these strategies have a mediating effect on the association between interpersonal needs and suicidal behavior. Conclusions: Our findings show that contextual-interpersonal needs, which underpin suicidal behavior, are significantly influenced by maladaptive emotional processes. Thus, therapeutic outcomes might be enhanced by focusing on the content of the associated cognitions and trying to reduce maladaptive regulatory processes like rumination and catastrophization.Publication Metadata only Anxiety disorders comorbidity in pediatric bipolar disorder: a meta-analysis and meta-regression study(Wiley, 2020) Morey Özcan, Aslıhan; Ongur, Dost; N/A; N/A; N/A; N/A; N/A; N/A; N/A; Eser, Hale Yapıcı; Taşkıran, Ali Sarper; Ertınmaz, Beliz; Mutluer, Tuba; Kılıç, Özge; Necef, Işıl; Yalçınay-İnan, Merve; Faculty Member; Teaching Faculty; Undergraduate Student; Faculty Member; Doctor; Doctor; Koç University Hospital; N/A; N/A; Koç University Hospital; N/A; Koç University Hospital; N/A; Koç University Hospital; 134359; 195168; N/A; 305311; 167890; N/A; N/A; N/AObjective Anxiety disorders (AD) are known for its comorbidity and negative impact on the course of adult bipolar disorder (BD). However, there is limited research on AD comorbidity in pediatric BD (PBD). Here, we aimed to conduct a meta-analysis and meta-regression study about the comorbidity and covariates of AD and PBD. Method We systematically searched relevant articles published until May 2019, as defined in PRISMA guidelines. Variables for associated features and prevalence of AD were extracted. Results Thirty-seven articles represented data for the analysis. Lifetime any AD comorbidity was 44.7%; panic disorder (PD) was 12.7%; generalized anxiety disorder (GAD) was 27.4%; social phobia was 20.1%; separation anxiety disorder (SAD) was 26.1%; and obsessive-compulsive disorder (OCD) was 16.7%. Childhood-onset studies reported higher GAD and SAD comorbidity, while adolescent-onset studies reported higher PD, OCD, and social phobia. Age of onset, gender, comorbidity of ADHD, substance use, oppositional defiant disorder and conduct disorder affected each anxiety disorders' comorbidity with PBD differently. Conclusion Anxiety disorders are highly comorbid with PBD. Early-onset PBD increases the risk of AD. Biopsychosocial aspects of this comorbidity and its course needs to be evaluated further.