Maintenance Electroconvulsive Therapy

Since the other treatment options did not meet the expectations in treatment resistant patients, maintenance electroconvulsive therapy (m-ECT) recently regained interest as a treatment option . Although it has long been applied as a treatment, studies of m-ECT lacks strong evidence for effectiveness, safety and the choice of application method because of problems regarding methodology, small sample sizes and scarcity of randomized, double-blind, controlled trials. Besides several points about treatment remains uncertain. Some of these troubled points are the selection of patients that will receive m-ECT, schedule and procedure of the application, the duration of the treatment, the assessment and follow-up of side effects and concomitant medication with drugs. Therefore, some guidelines recommended it for a particular group of patients and some rejected its application with a cautious consideration. The terminology, applications and rationales in different disorders, possible side effects and concomitant drug use are discussed in this review. Further studies with broader samples are needed to clarify the issues of effectiveness and adverse events in m-ECT

Comparison of Alcohol Attentional Bias and Alcohol Craving Among Alcohol Abusers and Non-Abusers

The aim of this research is to investigate implicit cognitive process underlying alcohol craving and relationship between alcohol attentional bias and alcohol craving by using visual probe task. Current study examined whether alcohol abusers show attentional bias toward alcohol related task compared with non- abusers and causal relationship between alcohol attentional bias and alcohol craving. Firstly, participants were divided two groups (non abusers- abusers) and they were completed alcohol craving scale to determinate their alcohol craving level. Then, participants alcohol attentional bias was investigated using the visual probe task. In this task, images (alcohol-related and neutral) were presented for 500 ms on a computer screen. After that, probe (*, asterisk) was presented. Participants were asked to decide the place of the probe place by using keyboard keys within 1500 ms. Participants reaction time and number of correct and incorrect answers during the test. According to results, alcohol abuser group’s reaction times were faster than non-abuser when probe was associated with alcohol picture but not in neutral trials. These results suggested that, alcohol abusers showed significantly greater attentional bias to alcohol related pictures than non- abusers. From this point, investigation of alcohol attentional bias might be important component of alcohol dependence in terms of the alcohol relapse risk and determination of the alcohol craving

Multimodal bağlantı analizleri

Amaç: Yaratıcı düşünce ve usavurma, insan beyninin bilişsel kapasitesinin hiyerarşik olarak en tepesindeki ve en karmaşık sistemleridir. Birbirleri arasında dinamik bir etkileşim içerisinde olan bu iki kavram, insan ve toplum hayatının daha sürdürülebilir ve kaliteli olması açısından büyük bir stratejik öneme sahiptirler. Bu konuda uzun yıllardır pek çok bilimsel çalışma yapılmasına rağmen bu süreçlerin ardındaki nöral bileşenler ve sistemler hakkında kapsamlı çalışmalar son yıllara kadar yapılamamıştır. Gelişen teknik imkanların da yardımıyla, "Semantik Uzaklık" ve "Anoloji Tabanlı Usavurma" , fMRI görevi olarak modellenebilmiş ve yaratıcı düşünce araştırmaları konusuna yeni yöntemler ve bilgiler sağlamıştır. Bu çalışmanın amacı, kullanılan MR modalitelerini arttırarak (rs-fMRI,dwMRI) sadece görev sırasında aktive olan bölgeleri değil tüm beyni bir bütün ağ ve alt parçaları olarak değerlendirmek, yaratıcı düşüncenin oluşumunda katkıda bulunan bölge ve sistemlerin aktivasyon ve dinlenme sırasında nasıl bir fonksiyonel bağlantıya sahip olduklarını açıklamaktır. Yöntem: Çalışmaya 20-35 yaş arası, kendilerinde ve ailelerinde herhangi bir psikiyatrik bozukluk bulunmayan, en az lise mezunu, 30 sağlıklı gönüllü katılımcı dahil edilmiştir. Tüm katılımcıların MR taramaları Ege Üniversitesi Hastanesi 3T MR ünitesinde daha önce test edilen, çalışmaya en uygun parametreler kullanılarak yapılmıştır. Her katılımcı için yapısal olarak 3D-T1 ağırlıklı MP-RAGE ve 60 yönlü dwMRI, fonksiyonel olarak ise gözler kapalı 9 dakikalık rsfMRI ve "Analoji Tabanlı Usavurma" görevi sırasında BOLD fMRI görüntüleri elde edilmiştir. Tüm görüntüler kalite kontrolü ve ön işlemlerden geçirildikten sonra, fonksiyonel görüntüler üzerinde Freesurfer yazılım paketi ile "Semantik Uzaklık" kullanılarak parametrik modülasyon analizleri ve dinlenme halinde iken CONN MATLAB paketi ile ROIROI bağlantı analizleri yapılmıştır. Difüzyon ağırlıklı görüntülerde ise yine her katılımcı için FSL-ProbtrackX-Tracula yazılımları ile global probabilistik traktografi yapılmış ve fonksiyonel verilerde elde edilen kortikal yüzeylerin bağlantıları analiz edilmiştir. Kullanılan tüm yazılımlar ve araçlar açık kaynak kodlu olup modaliteler arası maksimum uygun hale getirmek için herbirinde gerekli düzenlemeler yapılmıştır. Bulgular: "Analoji Tabanlı Usavurma" görevi sırasında semantik uzaklığın artmasıyla görevde daha iyi performans gösteren bireylerin sol hemisfer gri madde yüzeyinde Intraparietal Sulcus, Anterior Cingulate Cortex-Ventral bölümü, Middle Frontal Gyrus, sağ hemisfer gri madde yüzeyinde Anterior Cingulate Cortex-Ventral bölümü alanlarında, subkoritkal analizlerde ise sağ ve sol Caudate Nucleus'ta, tüm beyin hata düzeltmelerinden sonra anlamlı BOLD sinyal korelasyonu saptandı.. Görevde daha başarılı olan katılımcıların dinlenme sırasında sol IPS ve sağ Inferior Frontal Junction kortikal bölgeleri arasında fonsiyonel korelasyon bulunduğu saptandı (T=4.77, p.0221). Difüzyon görüntülerinde 16 ana beyaz madde yolağında yapılan global probabilistik analizler sonucunda görev performansı ile bu yolaklar arasında anlamlı bir korelasyon bulunamamıştır. Ancak beyaz madde yüzeyinde ROI tabanlı probabilistik traktografi analizlerine uygulanan Çizge Teorisi sonucu, sol hemisfer Medial OFC, Pars Orbitalis ,ACC Rostral, Amigdala ve sağ hemisferde Pars Triangularis, Precentral Gyrus, Postcentral Gyrus, Superior Frontal Gyrus ve Cuneus'ta görev başarısıyla anlamlı korelasyon bulunmuştur. Sonuç: Yaratıcı düşünce ve usavurmanın daha önceki çalışmalarda da belirlenen kortikal bölgelerin daha aktif kullanılmasıyla daha başarılı hale geldiği görülmektedir. Çalışmamız bu bilgilere dinlenme halindeki fonksiyonel bağlantı ve traktografi sonuçlarını ekleyerek yaratıcı düşüncenin salt aktivasyonun yanında ağ özellikleri açısından da ayırt edilebilir bileşenlerini göstermesi açısından oldukça önemlidir. Önümüzdeki çalışmalarda bu bölgelerin tekil bağlantılarının da incelip daha detaylı bir ağ haritası çıkarılması hedeflenmektedir.Introduction: Creative thinking and reasoning are the paramount of human cognitive capacity and one of the most complex systems. These 2-way interactive and dynamic systems have a great strategic value in terms of sustainability and quality of human life. In spite of many scientific research done in this area, underlying neural mechanisms of these cognitive processes have not been discovered yet. With help of advances in neuroimaging it has been possible to model an fMRI experiment using “Semantic Distance” and “Analogy Based Reasoning”. Aim of this study is, investigate whole brain and its sub-divisions as a network and interacting pair of nodes while performing an analogy based reasoning test and resting state by increaisng the number of MRI modalities with rs-fMRI and dwMRI. Method: 30 participants aged between 20-35, who doesn’t have any psychiatric disorders have been included in this study. All MR scans are completed at Ege University Hospital 3T MR Unit, using previously selected best fit parameters. 3D T1-wieghted MP-RAGE and 60 directions dwMRI data collected for structural and 28 minutes task-based and 9 minutes resting state fMRI data collected for functional analysis. After quality control and preprocessing steps all data analysed using Freesurfer software suite and CONN toolbox. Diffusion weighted images analysed with FSL-ProbtrackX-Tracula software using gloval probabilistic tractography, assesing connectivity of gray matter surfaces. All software was used on this study was open source and licensed under GPL. Results: We found significant BOLD signal correlated regions in the left hemisphere Intraparietal Sulcus, Anterior Cingulate Cortex-Ventral part, Middle Frontal Gyrus, in the right hemisphere Anterior Cingulate Cortex-Ventral part and in subcortical areas, right and left Caudate Nucleus. Left IPS and right IFJ were significantly correlated with task performance while in resting state and therefore showed a strong functional connection. We analysed 16 major white matter tracts using global probabilistic tractography, but couldn't find any significant correlations. However, applying Graph Theory analysis of ROI based probabilistic tractography using whitematter surfaces, we found significant correlations between task score and vertexlevel attributes in the following areas; left hemi: Medial OFC, Pars Orbitalis ,ACC Rostral, Amigdala and right hemi: Pars Triangularis, Precentral Gyrus, Postcentral Gyrus, Superior Frontal Gyrus and Cuneus. Conclusion: Similar cortical regions were found correlated with creative thinking and reasoning as previous studies suggested. In addition to previous findings we showed functional and structural connectivity properties of the human brain in relation with creativity and reasoning. In future studies it is important to asses the connectivity of these spesific areas and their network properties as they are shown to be linked with creativity and reasoning

Chasing Sea Horses in the Depressed Seas: A Ten Years Journey

[Özet Yok

Brain-derived neurotrophic factor, stress and depression: A minireview

Brain-derived neurotrophic factor (BDNF) is a member of the nerve growth factor family, and is widely expressed in the adult mammalian brain. Besides its well known neuroprotective activity after traumatic brain injury the evidences regarding its activity dependent release by the pathophysiology of major depression are rapidly replicating. Considering the data that stress plays an important role by the development of depression which is characterized with prominent hippocampal cell death, as well as the well known neuroprotective effects of BDNF, we aimed to investigate the link between the BDNF, stress and depression. Thus we prepared a minireview in order to evaluate the neuroprotective role of BDNF by psychiatric disorders which are characterized with prominent neuronal cell death

Cerebral blood flow, metabolic, receptor, and transporter changes in bipolar disorder: The role of PET and SPECT studies

The basic concepts of positron emission tomography (PET) and single photon emission computed tomography ( SPECT) scanning are introduced, and the two modalities are compared. Applications to bipolar disorder ( BD) are reviewed. Regional cerebral metabolic rate and blood flow, often used as surrogate measures of neuronal synaptic activity, are increased in the frontal lobes in both unipolar and bipolar depression. In mania, metabolism increases in the dorsal cingulate cortex, striatal regions, and the nucleus accumbens, as well as in limbic structures of the temporal lobes, but decreases in dorsolateral prefrontal cortex, possibly reflecting its loss of modulatory control over limbic structures. Specifically targeted PET radioligands are used to investigate neurotransmitter systems. D1 receptor binding potentials are reduced in frontal cortex, but striatal D2 receptor density is normal in all phases of non-psychotic BD. Psychotic BD patients show higher D2 receptor densities in the caudate, which correlate with the degree of psychosis but not mood symptoms. The serotonin transporter shows increased density in the thalamus, dorsal cingulate cortex, medial preftontal cortex, and insula of depressed BD patients. In the dorsal cingulate cortex and insula, it correlates with anxiety (and in the cingulate, with suicide attempts)

Reliability Assessment of Denoising Methods for Change Point and Activation Detection in Lack of Ground Truth from fMRI

© 2020 IEEE.This study presents and discusses the outcomes of different de-noising approaches, which are applied to low SNR real fMRI BOLD signals. These signals are acquired during a psychiatric fMRI experiment that is specifically designed for observing emotional mood changes (EMC). Despite a priori knowledge about activations and change points for motor tasks, EMC signals in this study do not have a ground truth. Up to our knowledge, the challenges of such a task has never been visited. Accordingly, this study aims to compare the performance of three de-noising methods, which have inherently different characteristics, on preserving the waveform characteristics of change points and activation durations while removing noise from EMC-BOLD signals through expert guided qualitative analysis